Indoor Human Navigation Systems: A Survey
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paper_title: Wayfinding and navigation in haptic virtual environments

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Cognitive maps are mental models of the relative locations and attribute phenomena of spatial environments. The ability to form cognitive maps is one of the innate gifts of nature. An absence of this ability can have crippling effect, for example, on the visually impaired. The sense of touch becomes the primary source of forming cognitive maps for the visually impaired. Once formed, cognitive maps provide precise mapping of the physical world so that a visually impaired individual can successfully navigate with minimal assistance. However, traditional mobility training is time consuming, and it is very difficult for the blind to express or revisit the cognitive maps formed after a training session is over. The proposed haptic environment will allow the visually impaired individual to express cognitive maps as 3D surface maps, with two PHANToM force-feedback devices guiding them. The 3D representation can be finetuned by the care-giver, and then felt again by the visually impaired in order to form precise cognitive maps. In addition to voice commentary, a library of pre-existing shapes familiar to the blind will provide orientation and proprioceptive haptic-cues during navigation. A graphical display of cognitive maps will provide feedback to the care-giver or trainer. As the haptic environment can be easily stored and retrieved, the MoVE system will also encourage navigation by the blind at their own convenience, and with family members.
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paper_title: Navigating without vision: Basic and applied research

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We describe some of the results of our program of basic and applied research on navigating without vision. One basic research topic that we have studied extensively is path integration, a form of navigation in which perceived self-motion is integrated over time to obtain an estimate of current position and orientation. In experiments on pathway completion, one test of path integration ability, we have found that subjects who are passively guided over the outbound path without vision exhibit significant errors when attempting to return to the origin but are nevertheless sensitive to turns and segment lengths in the stimulus path. We have also found no major differences in path integration ability among blind and sighted populations. A model we have developed that attributes errors in path integration to errors in encoding the stimulus path is a good beginning toward understanding path integration performance. In other research on path integration, in which optic flow information was manipulated in addition to the proprioceptive and vestibular information of nonvisual locomotion, we have found that optic flow is a weak input to the path integration process. In other basic research, our studies of auditory distance perception in outdoor environments show systematic underestimation of sound source distance. Our applied research has been concerned with developing and evaluating a navigation system for the visually impaired that uses three recent technologies: the Global Positioning System, Geographic Information Systems, and virtual acoustics. Our work shows that there is considerable promise of these three technologies in allowing visually impaired individuals to navigate and learn about unfamiliar environments without the assistance of human guides.
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paper_title: Learning Building Layouts with Non-Geometric Visual Information: The Effects of Visual Impairment and Age

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Previous studies suggest that humans rely on geometric visual information (hallway structure) rather than non-geometric visual information (eg doors, signs, and lighting) for acquiring cognitive maps of novel indoor layouts. In this study we asked whether visual impairment and age affect reliance on non-geometric visual information for layout learning. We tested three groups of participants—younger (<50 years of age) normally sighted; older (50–70 years of age) normally sighted; and low-vision (people with heterogeneous forms of visual impairment ranging in age from 18 to 67 years). Participants learned target locations in building layouts using four presentation modes: a desktop virtual environment (VE) displaying only geometric cues (sparse VE); a VE displaying both geometric and non-geometric cues (photorealistic VE); a map; and a real building. Layout knowledge was assessed by map drawing and by asking participants to walk to specified targets in the real space. Results indicate that low-vision and ol...
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paper_title: The Spatio-Cognitive Abilities of the Visually Impaired Population:

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This article reports on an experiment undertaken to test the spatiocognitive competence of the visually impaired population in regard to wayfinding. The test consisted of eight basic wayfinding tasks, each representing a particular spatio-cognitive operation. The tasks were executed in a labyrinthian layout allowing for control of the difficulty level of the tasks and limiting extraneous perceptual factors, which tended to interfere with the measure of spatio-cognitive abilities. The experimental groups were composed of congenitally totally blind, adventitiously totally blind, and subjects with a weak visual residue; the control was established by a sighted and a sighted blindfolded group. The sample's 18 subjects per group were matched in terms of age, education, and sex. The performance results of the visually impaired groups in all eight tasks led to rejection of any spatio-cognitive deficiency theory. The performance of the congenitally totally blind group, in particular, shows that spatio-cognitive c...
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paper_title: Geography and the disabled: a survey with special reference to vision impaired and blind populations

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Traditionally, geography has paid relatively little attention to disabled or disadvantaged populations. As society has concerned itself more with problems of dealing with the blind, the physically handicapped, the retarded, the deaf, the socioeconomically destitute and homeless, and other special populations, the discipline of geography has dragged its feet in terms of examining how its expertise can be used to help understand and solve the many problems these special populations encounter in normal commerce with physical and built environments. In this paper I outline some general and some specific suggestions regarding the way geographers can invoke their skills and knowledge to deal with sets of problems faced by these special populations. The paper is designed to make suggestions both for instructional purposes (i.e., providing a sufficiently wide topical coverage for potential course-work in the area), and to identify specific future research challenges. The combined effect is to suggest that geographical study of the disabled could represent a new systematic area of geographic concentration that would combine micro and macro approaches, and facilitate the development of new geographic theory, methods, and applications.
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paper_title: Challenges to Global RFID Adoption

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Because of its promise to revolutionize global supply chain management (SCM) systems, Ultra High Frequency (UHF) Radio Frequency Identification (RFID) was recently the cause of much optimism. Wal-Mart mandated its top 100 suppliers to begin using RFID on January 1st, 2005; this day was viewed as a watershed day in the industry. However, that date has come and gone, and the expected rapid industry adoption of RFID has not taken place. This paper explores the existing challenges and obstacles to RFID's quick adoption, the potential resolutions and approaches to the challenges, and the migration strategies to expand the RFID industry.
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paper_title: Design and development of an indoor navigation and object identification system for the blind

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In this paper we present a new system that assists blind users in orienting themselves in indoor environments. We developed a sensor module that can be handled like a flashlight by a blind user and can be used for searching tasks within the three-dimensional environment. By pressing keys, inquiries concerning object characteristics, position, orientation and navigation can be sent to a connected portable computer, or to a federation of data servers providing models of the environment. Finally these inquiries are acoustically answered over a text-to-speech engine.
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paper_title: Path Planning and Following Algorithms in an Indoor Navigation Model for Visually Impaired

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This paper describes, path planning and following algorithms for use in indoor navigation for the blind and visually impaired. Providing indoor navigational assistance for this type of users presents additional challenges not faced by conventional guidance systems, due to the personal nature of the interactions. The algorithms are part of an overall Indoor Navigation Model that is used to provide assistance and guidance in unfamiliar indoor environments. Path planning uses the A* and Dijkstra's shortest path algorithms, to operate on an "Intelligent Map", that is based on a new data structure termed "cactus tree" which is predicated on the relationships between the different objects that represent an indoor environment. The paths produced are termed "virtual hand rails", which can be used to dynamically plan a path for a user within a region. The path following algorithm is based on dead reckoning, but incorporates human factors as well as information about the flooring and furnishing structures along the intended planned path. Experimental and simulating results show that the guiding/navigation problem becomes a divergent mathematical problem if the positional information offered by the positioning and tracking systems does not reach a certain requirement. This research explores the potential to design an application for the visually impaired even when to- date 'positioning and tracking' system cannot offer reliable position information that highly required by this type of application.
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paper_title: Pedestrian navigation systems and location-based services

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Pedestrians must often find their way in unfamiliar urban environments or complex buildings. In these cases they need guidance to reach their desired destination, for example a specific room in a local authorities' building, a counter, or a department at an university. The goal of location-based mobile services is to provide such guidance on demand (anywhere, anytime), individually tailored to the actual information needs and presented in preferred forms. Thereby the navigation service requires positioning and tracking capabilities of a mobile user with a certain positioning accuracy and reliability. In particular, navigating in urban areas is a very challenging task as pedestrians move in spaces where none of the known positioning techniques works continuously in standalone mode and the movement is in a much more complex space than 2D networks (i.e. on pedestrian paths and along roads, outdoor and indoor, through underground passages, etc.). To solve this challenging task of continuous position determination, a combination of different location technologies is required. The integration of the sensors should be performed such that all the sensors are tightly coupled in the sense of a so-called multi-sensor system. In a new research project in our University entitled "Pedestrian Navigation Systems in Combined Indoor/Outdoor Environments (NAVIO)" we are working on the improvement of such navigation services. The project is mainly focusing on the information aspect of location-based services, i.e. on the user's task at hand and support of the user's decisions by information provided by such a service. Specifications will allow selection of appropriate sensor data and to integrate data when and where needed, to propose context-dependent routes fitting to partly conflicting interests and goals as well as to select appropriate communication methods in terms of supporting the user guiding by various multimedia cartography forms. To test and to demonstrate our approach and results, the project takes a use case scenario into account, i.e. the guidance of visitors to departments of the Vienna University of Technology. First results of our project are presented in this paper.
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paper_title: 3-D human navigation system considering various transition preferences

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Walking is the most fundamental means of human transportation. Unlike travel by car, walking is not planar, but rather stereoscopic. We therefore developed a real navigation system for pedestrian point-to-point navigation. We propose herein a method of 3D pedestrian navigation, in which position detection is driven mainly by dead reckoning. The proposed method enables ubiquitous round-the-clock 3D positioning, even inside buildings or between tall buildings. In addition, pedestrian navigation is customized by changing the costs of the road network links. Finally, a positioning data accumulation system is implemented so that we can log tracks and easily incorporate new roads or attributes in the future.
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paper_title: A walking navigation system for the blind

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This paper proposes a walking navigation system for the blind. The system is based on a comparison of data obtained by a pedometer and a terrestrial magnetic sensor and prearranged teaching data of a route to a destination. The system gives an appropriate instruction (using voice and buzzer sound) during a user's walk. This paper mainly describes experiments designed to clarify the characteristics of the system. The results show that the nodes of a walking route for teaching should be less than 50 m, since the maximum error of the system is about 10% in a walking distance of 50 m. The experiments also show that the walkers (sighted men with eye masks) were guided by the system along a course of about 900 m, taking about 40 to 50 mins. © 1998 Scripta Technica. Syst Comp Jpn, 28(13): 36–45, 1997
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paper_title: Ultrasound-aided pedestrian dead reckoning for indoor navigation

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Ad hoc solutions for tracking and providing navigation support to emergency response teams is an important and safety-critical challenge. We propose a navigation system based on a combination of foot-mounted inertial sensors and ultrasound beacons. We evaluate experimentally the performance of our dead reckoning system in different environments and for different trail topologies. The inherent drift observed in dead reckoning is addressed by deploying ultrasound beacons as landmarks. We study through simulations the use of the proposed approach in guiding a person along a defined path. ::: Simulation results show that satisfactory guidance performance is achieved despite noisy ultrasound measurements, magnetic interference and uncertainty in ultrasound node locations. The models used for the simulations are based on experimental data and the authors' experience with actual sensors. The simulation results will be used to inform future development of a full real time system.
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paper_title: Steps Toward Accommodating Variable Position Tracking Accuracy in a Mobile Augmented Reality System

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The position-tracking accuracy of a location-aware mobile system can change dynamically as a function of the user’s location and other variables specific to the tracker technology used. This is especially problematic for mobile augmented reality systems, which ideally require extremely precise position tracking for the user’s head, but which may not always be able to achieve the necessary level of accuracy. While it is possible to ignore variable positional accuracy in an augmented reality user interface, this can make for a confusing system; for example, when accuracy is low, virtual objects that are nominally registered with real ones may be too far off to be of use. To address this problem, we describe the early stages of an experimental mobile augmented reality system that adapts its user interface automatically to accommodate changes in tracking accuracy. Our system employs different technologies for tracking a user’s position, resulting in a wide variation in positional accuracy: an indoor ultrasonic tracker and an outdoor real-time kinematic GPS system. For areas outside the range of both, we introduce a dead-reckoning approach that combines a pedometer and orientation tracker with environmental knowledge expressed in spatial maps and accessibility graphs. We present preliminary results from this approach in the context of a navigational guidance system that helps users to orient themselves in an unfamiliar environment. Our system uses inferencing and path planning to guide users toward targets that they choose.
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paper_title: GPS-less Low Cost Outdoor Localization For Very Small Devices

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Instrumenting the physical world through large networks of wireless sensor nodes, particularly for applications like environmental monitoring of water and soil, requires that these nodes be very small, lightweight, untethered, and unobtrusive. The problem of localization, that is, determining where a given node is physically located in a network, is a challenging one, and yet extremely crucial for many of these applications. Practical considerations such as the small size, form factor, cost and power constraints of nodes preclude the reliance on GPS of all nodes in these networks. We review localization techniques and evaluate the effectiveness of a very simple connectivity metric method for localization in outdoor environments that makes use of the inherent RF communications capabilities of these devices. A fixed number of reference points in the network with overlapping regions of coverage transmit periodic beacon signals. Nodes use a simple connectivity metric, which is more robust to environmental vagaries, to infer proximity to a given subset of these reference points. Nodes localize themselves to the centroid of their proximate reference points. The accuracy of localization is then dependent on the separation distance between two-adjacent reference points and the transmission range of these reference points. Initial experimental results show that the accuracy for 90 percent of our data points is within one-third of the separation distance. However, future work is needed to extend the technique to more cluttered environments.
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paper_title: Metronaut: a wearable computer with sensing and global communication capabilities

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Metronaut is a novel wearable computer which captures information, senses position, provides wide range communications, consumes less than one watt of power, and weighs less than one pound. Metronaut employs a bar code reader for information input and position location, a two-way pager for communications, and an ARM processor for computation. Metronaut's application is schedule negotiation and guidance instructions for a visitor to the CMU campus. The visitor's position is determined from reading bar codes at information signs around campus. Modifications to the schedule are negotiated using the two-way pager for communications with the campus computing infrastructure. Metronaut is alternatively powered by a mechanical flywheel converting kinetic energy to electrical energy.
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paper_title: A blind navigation system using RFID for indoor environments

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A location and tracking system becomes very important to our future world of pervasive computing, where information is all around us. Location is one of the most needed information for emerging and future applications. Since the public use of GPS satellite is allowed, several state-of-the-art devices become part of our life, e.g. a car navigator and a mobile phone with a built-in GPS receiver. However, location information for indoor environments is still very limited. Several techniques are proposed to get location information in buildings such as using a radio signal triangulation, a radio signal (beacon) emitter, or signal fingerprinting. Using radio frequency identification (RFID) tags is a new way of giving location information to users. Due to its passive communication circuit, RFID tags can be embedded almost anywhere without an energy source. The tags stores location information and gives it to any reader that is within a proximity range which can be up to 10-15 meters for UHF RFID systems. We propose an RFID-based system for navigation in a building for blind people or visually impaired. The system relies on the location information on the tag, a userpsilas destination, and a routing server where the shortest route from the userpsilas current location to the destination. The navigation device communicates with the routing server using GPRS networks. We build a prototype based on our design and show some results. We found that there are some delay problems in the devices which are the communication delay due to the cold start cycle of a GPRS modem and the voice delay due to the file transfer delay from a MMC module.
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paper_title: A space-identifying ubiquitous infrastructure and its application for tour-guiding service

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In this paper, a novel tour-guiding system is introduced, based on our space-identifying ubiquitous infrastructure, where positioning devices are deployed ubiquitously to identify the place of users. In this infrastructure, we can flexibly construct information service related to the places of interest in the city by modeling the space of the real world as a set of relations among the discrete places, and attaching space-identifying devices to them. Our developed tour-guiding system introduces many art works in a large commercial complex in Japan. Based on the benefit of the infrastructure, this system can provide detailed navigation service as well as art introduction service in both indoor and outdoor environments, and can guide the users to reach their interested art works. Currently, this system is already used in practice for a commercial service. In this paper, the design of this system is described and its navigation capability is verified through a user test in the real environment to discuss the effectiveness of our approach.
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paper_title: Challenges to Global RFID Adoption

paper_content:

Because of its promise to revolutionize global supply chain management (SCM) systems, Ultra High Frequency (UHF) Radio Frequency Identification (RFID) was recently the cause of much optimism. Wal-Mart mandated its top 100 suppliers to begin using RFID on January 1st, 2005; this day was viewed as a watershed day in the industry. However, that date has come and gone, and the expected rapid industry adoption of RFID has not taken place. This paper explores the existing challenges and obstacles to RFID's quick adoption, the potential resolutions and approaches to the challenges, and the migration strategies to expand the RFID industry.
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paper_title: Robot-assisted wayfinding for the visually impaired in structured indoor environments

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We present a robot-assisted wayfinding system for the visually impaired in structured indoor environments. The system consists of a mobile robotic guide and small passive RFID sensors embedded in the environment. The system is intended for use in indoor environments, such as office buildings, supermarkets and airports. We describe how the system was deployed in two indoor environments and evaluated by visually impaired participants in a series of pilot experiments. We analyze the system's successes and failures and outline our plans for future research and development.
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paper_title: A resource-adaptive mobile navigation system

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The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
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paper_title: Reducing the effects of artificial light interference in wireless infrared transmission systems

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The performance of wireless infrared transmission systems for indoor use is severely impaired by the noise and interference induced by natural and artificial ambient light. In order to combat the effects of ambient light on the system performance, both optical filtering and electrical filtering is usually adopted. However, even when resorting to these techniques, the optical power penalty imposed by the interference may be very large. In particular, the interference produced by fluorescent lamps driven by electronic ballasts imposes very large optical power penalties on systems operating at data rates up to a few tens of Mbps. In this paper, a different technique to overcome the penalty induced by artificial light interference is analysed. This technique explores the different optical spectra of the transmitted signal and the artificial light and the characteristics of optical filtering to cancel the interfering signal. Some aspects of its implementation are also discussed. The results obtained with this approach are shown to be much better than those obtained through electrical high-pass filtering. (10 pages)
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paper_title: A wearable haptic navigation guidance system

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This paper describes a wearable navigation system based on a haptic directional display embedded in the back of a vest. The system consists of a 4-by-4 array of micromotors for delivering haptic navigational signals to the user's back, an infrared-based input system for locating the user in an environment, and a wearable computer for route planning. User testing was conducted to evaluate the effectiveness of this system as a navigation guide for sighted users in an unfamiliar lab area. It is hoped that such a system can be a useful navigation guide for individuals with severe visual impairments in an unfamiliar environment. Future work will address the specific issues concerning blind navigation.
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paper_title: LANDMARC: indoor location sensing using active RFID

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Growing convergence among mobile computing devices and embedded technology sparks the development and deployment of “context-aware” applications, where location is the most essential context. In this paper we present LANDMARC, a location sensing prototype system that uses Radio Frequency Identification (RFID) technology for locating objects inside buildings. The major advantage of LANDMARC is that it improves the overall accuracy of locating objects by utilizing the concept of reference tags. Based on experimental analysis, we demonstrate that active RFID is a viable and cost-effective candidate for indoor location sensing. Although RFID is not designed for indoor location sensing, we point out three major features that should be added to make RFID technologies competitive in this new and growing market.
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paper_title: Development of a Wearable Computer Orientation System

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People with severe visual impairment need a means of remaining oriented to their environment as they move through it. A series of indoor and outdoor trials using a variety of technologies and interfaces led to the development and evaluation of three promising wearable orientation interfaces: a virtual sonic beacon, speech output, and a shoulder-tapping system. Street crossing was used as a critical test situation in which to evaluate these interfaces. The shoulder-tapping system was found most universally usable. Results indicated that, given the great variety of co-morbidities within this population, which is comprised of mostly older persons, optimal performance and flexibility may best be obtained in a design that combines the best elements of both the speech and shoulder-tapping interfaces.
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paper_title: Virtual leading blocks for the deaf-blind: a real-time way-finder by verbal-nonverbal hybrid interface and high-density RFID tag space

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In this paper, we discuss application possibilities of augmented reality technologies in the field of mobility support for the deaf blind. We propose the navigation system called virtual leading blocks for the deaf-blind, which consists of a wearable interface for Finger-Braille, one of the commonly used communication methods among deaf-blind people in Japan, and a ubiquitous environment for barrier-free application, which consists of floor-embedded active radio-frequency identification (RFID) tags. The wearable Finger-Braille interface using two Linux-based wristwatch computers has been developed as a hybrid interface of verbal and nonverbal communication in order to inform users of their direction and position through the tactile sensation. We propose the metaphor of "watermelon splitting" for navigation by this system and verify the feasibility of the proposed system through experiments.
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paper_title: The user as a sensor: navigating users with visual impairments in indoor spaces using tactile landmarks

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Indoor navigation systems for users who are visually impaired typically rely upon expensive physical augmentation of the environment or expensive sensing equipment; consequently few systems have been implemented. We present an indoor navigation system called Navatar that allows for localization and navigation by exploiting the physical characteristics of indoor environments, taking advantage of the unique sensing abilities of users with visual impairments, and minimalistic sensing achievable with low cost accelerometers available in smartphones. Particle filters are used to estimate the user's location based on the accelerometer data as well as the user confirming the presence of anticipated tactile landmarks along the provided path. Navatar has a high possibility of large-scale deployment, as it only requires an annotated virtual representation of an indoor environment. A user study with six blind users determines the accuracy of the approach, collects qualitative experiences and identifies areas for improvement.
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paper_title: Semantically enriched navigation for indoor environments

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Location-based mobile services have been in use, and studied, for a long time. With the proliferation of wireless networking technologies, users are mostly interested in advanced services that render the surrounding environment (i.e., the building) highly intelligent and significantly facilitate their activities. In this paper our focus is on indoor navigation, one of the most important location services. Existing approaches for indoor navigation are driven by geometric information and neglect important aspects, such as the semantics of space and user capabilities and context. The derived applications are not intelligent enough to catalytically contribute to the pervasive computing vision. In this paper, a novel navigation mechanism is introduced. Such navigation scheme is enriched with user profiles and the adoption of an ontological framework. These enhancements introduce a series of technical challenges that are extensively discussed throughout the paper.
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paper_title: Location Systems for Ubiquitous Computing

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This survey and taxonomy of location systems for mobile-computing applications describes a spectrum of current products and explores the latest in the field. To make sense of this domain, we have developed a taxonomy to help developers of location-aware applications better evaluate their options when choosing a location-sensing system. The taxonomy may also aid researchers in identifying opportunities for new location-sensing techniques.
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paper_title: A context aware handheld wayfinding system for individuals with cognitive impairments

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A challenge to individuals with cognitive impairments in wayfinding is how to remain oriented, recall routines, and travel in unfamiliar areas in a way relying on limited cognitive capacity. According to psychological model of spatial navigation and the requirements of rehabilitation professionals, a novel wayfinding system is presented with an aim to increase workplace and life independence for people suffering from diseases such as traumatic brain injury, cerebral palsy, mental retardation, schizophrenia, Down syndromes, and Alzheimer's disease. This paper describes an approach to providing distributed cognition support of travel guidance for persons with cognitive disabilities. The unique strength of the system is the ability to provide unique-to-the-user prompts that are triggered by context. As this population is very sensitive to issues of abstraction (e.g. icons) and presents the designer with the need to tailor prompts to a 'universe-of-one' the use of images specific to each user and context is implemented. The key to the approach is to spread the context awareness across the system, with the context being flagged by the QR-code tags and the appropriate response being evoked by displaying the appropriate path guidance images indexed by the intersection of specific end-user and context ID embedded in the tags. By separating the context trigger from the pictorial response, responses can be updated independently of the rest of the installed system, and a single QR-code tag can trigger multiple responses in the PDA depending on the end-user and their specific path. A prototype is built and tested in field experiments with real patients. The experimental results show the human-computer interface is friendly and the capabilities of wayfinding are reliable.
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paper_title: The Cricket location-support system

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This paper presents the design, implementation, and evaluation of Cricket , a location-support system for in-building, mobile, location-dependent applications. It allows applications running on mobile and static nodes to learn their physical location by using listeners that hear and analyze information from beacons spread throughout the building. Cricket is the result of several design goals, including user privacy, decentralized administration, network heterogeneity, and low cost. Rather than explicitly tracking user location, Cricket helps devices learn where they are and lets them decide whom to advertise this information to; it does not rely on any centralized management or control and there is no explicit coordination between beacons; it provides information to devices regardless of their type of network connectivity; and each Cricket device is made from off-the-shelf components and costs less than U.S. $10. We describe the randomized algorithm used by beacons to transmit information, the use of concurrent radio and ultrasonic signals to infer distance, the listener inference algorithms to overcome multipath and interference, and practical beacon configuration and positioning techniques that improve accuracy. Our experience with Cricket shows that several location-dependent applications such as in-building active maps and device control can be developed with little effort or manual configuration.
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paper_title: Low-latency indoor localization using bluetooth beacons

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Indoor localization refers to the task of determining the location of a traveler in spaces (such as large building complexes or airport terminals) using coordinates appropriate to those spaces (such as floor and room number or airport terminal and gate). Indoor localization using Bluetooth beacons is attractive because of the low cost and high spatial selectivity of Bluetooth devices. However, a significant drawback of the Bluetooth protocol for this application is the large delay incurred in the discovery phase of the protocol, which is the phase used for detecting beacons. These delays, of approximately 20 seconds, hamper the use of this localization method because typical walking speeds are likely to change the set of potentially visible beacons part-way through the discovery phase. We study the causes of these delays and propose methods for alleviating them for indoor localization applications. We formalize the key problem of finding a minimum-cost complete beacon-probing plan and present an algorithm for generating such plans.
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paper_title: Survey of Wireless Indoor Positioning Techniques and Systems

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Wireless indoor positioning systems have become very popular in recent years. These systems have been successfully used in many applications such as asset tracking and inventory management. This paper provides an overview of the existing wireless indoor positioning solutions and attempts to classify different techniques and systems. Three typical location estimation schemes of triangulation, scene analysis, and proximity are analyzed. We also discuss location fingerprinting in detail since it is used in most current system or solutions. We then examine a set of properties by which location systems are evaluated, and apply this evaluation method to survey a number of existing systems. Comprehensive performance comparisons including accuracy, precision, complexity, scalability, robustness, and cost are presented.
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paper_title: Smart Environment for Ubiquitous Indoor Navigation

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Mobile navigation service is one of the most important Location Based Services. With the rapid advances in enabling technologies for ubiquitous computing, more and more active or passive devices/sensors are augmented in the indoor environment, indoor environment has become smarter. This paper proposes that by introducing the notions of Smart Environment and Ambient Intelligent, a ubiquitous indoor navigation service can be built to provide an adaptive smart wayfinding support and enhance users with a new experience during indoor navigation. In this paper, we set up a smart environment with a positioning module and a wireless module. Based on this smart environment, we design a ubiquitous indoor navigation system with interaction and annotation module (for user generated content), user tracking module (for collaborative filtering) and context-aware adaptation to illustrate some potential benefits of combining indoor navigation and Smart Environment.
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paper_title: NAVIO ? A Navigation and Guidance Service for Pedestrians

paper_content:

In the research project NAVIO (Pedestrian Navigation Systems in Combined Indoor/Outdoor Environements) at our University we are working on the improvement of navigation services for pedestrians. Thereby we are mainly focusing on the information aspect of location-based services, i.e., on the user’s task at hand and the support of the user’s decisions by information provided by such a service. Specifications will allow us to select appropriate sensor data and to integrate data when and where needed, to propose context-dependent routes fitting to partly conflicting interests and goals as well as to select appropriate communication methods in terms of supporting the user guidance by various multimedia cartography forms. These taks are addressed in the project in three different work packages, i.e., the first on “Integrated positioning”, the second on “Pedestrian route modeling” and the third on “Multimedia route communication”. In this paper we will concentrate on the research work and findings in the first work package. For continuous positioning of a pedestrian suitable location technologies include GNSS and indoor location techniques, cellular phone positioning, dead reckoning sensors (e.g. magnetic compass, gyro and accelerometers) for measurement of heading and travelled distance as well as barometric pressure sensors for height determination. The integration of these sensors in a modern multi-sensor system can be performed using an adapted Kalman filter. To test and to demonstrate our approach, we take a use case scenario into account, i.e., the guidance of visitors to departments of the Vienna University of Technology. The results of simulation studies and practical tests could confirm that such a service can achieve a high level of performance for the guidance of a pedestrian in urban areas and mixed indoor and outdoor environments.
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paper_title: A resource-adaptive mobile navigation system

paper_content:

The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
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paper_title: Drishti: an integrated navigation system for visually impaired and disabled

paper_content:

Drishti is a wireless pedestrian navigation system. It integrates several technologies including wearable computers, voice recognition and synthesis, wireless networks, Geographic Information System (GIS) and Global positioning system (GPS). Drishti augments contextual information to the visually impaired and computes optimized routes based on user preference, temporal constraints (e.g. traffic congestion), and dynamic obstacles (e.g. ongoing ground work, road blockade for special events). The system constantly guides the blind user to navigate based on static and dynamic data. Environmental conditions and landmark information queried from a spatial database along their route are provided on the fly through detailed explanatory voice cues. The system also provides capability for the user to add intelligence, as perceived by, the blind user, to the central server hosting the spatial database. Our system is supplementary to other navigational aids such as canes, blind guide dogs and wheel chairs.
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paper_title: Virtual leading blocks for the deaf-blind: a real-time way-finder by verbal-nonverbal hybrid interface and high-density RFID tag space

paper_content:

In this paper, we discuss application possibilities of augmented reality technologies in the field of mobility support for the deaf blind. We propose the navigation system called virtual leading blocks for the deaf-blind, which consists of a wearable interface for Finger-Braille, one of the commonly used communication methods among deaf-blind people in Japan, and a ubiquitous environment for barrier-free application, which consists of floor-embedded active radio-frequency identification (RFID) tags. The wearable Finger-Braille interface using two Linux-based wristwatch computers has been developed as a hybrid interface of verbal and nonverbal communication in order to inform users of their direction and position through the tactile sensation. We propose the metaphor of "watermelon splitting" for navigation by this system and verify the feasibility of the proposed system through experiments.
---
paper_title: MOBIC: Designing a Travel Aid for Blind and Elderly People

paper_content:

This paper presents the research for the development of a new travel aid to increase the independent mobility of blind and elderly travellers. This aid will build on the technologies of geographical information systems (GIS) and the Global Positioning System (GPS). The MOBIC Travel Aid (MOTA) consists of two interrelated components : the MOBIC Pre-journey System (MOPS) to assist users in planning journeys and the MOBIC Outdoor System (MooDs) to execute these plans by providing users with orientation and navigation assistance during journeys. The MOBIC travel aid is complementary to primary mobility aids such as the long cane or guide dog. Results of a study of user requirements are presented and their implications for the initial design of the system are discussed.
---
paper_title: Semantically enriched navigation for indoor environments

paper_content:

Location-based mobile services have been in use, and studied, for a long time. With the proliferation of wireless networking technologies, users are mostly interested in advanced services that render the surrounding environment (i.e., the building) highly intelligent and significantly facilitate their activities. In this paper our focus is on indoor navigation, one of the most important location services. Existing approaches for indoor navigation are driven by geometric information and neglect important aspects, such as the semantics of space and user capabilities and context. The derived applications are not intelligent enough to catalytically contribute to the pervasive computing vision. In this paper, a novel navigation mechanism is introduced. Such navigation scheme is enriched with user profiles and the adoption of an ontological framework. These enhancements introduce a series of technical challenges that are extensively discussed throughout the paper.
---
paper_title: Mobile Navigation Guide for the Visually Disabled

paper_content:

A location-aware navigation system has been developed and implemented for the visually disabled or visually impaired; the system is designed to improve individuals' independent mobility. This self-contained, portable system integrates several technologies, including mobile personal digital assistants, voice synthesis, a geographic information system (GIS), and a differential Global Positioning System (DGPS). The system is meant to augment the various sensory inputs available to the visually impaired user. It provides the user with navigation assistance, making use of voice cues iterating contextual building and feature information at regular intervals, through automatic GPS readings and a GIS database. To improve the efficiency of the retrieval of contextual information, an indexing method based on road segmentation was developed to replace the exhaustive search method. Experimental results show that the performance of the system on searching the buildings, landmarks, and other features around a road has been significantly improved by using this indexing method.
---
paper_title: The Cricket location-support system

paper_content:

This paper presents the design, implementation, and evaluation of Cricket , a location-support system for in-building, mobile, location-dependent applications. It allows applications running on mobile and static nodes to learn their physical location by using listeners that hear and analyze information from beacons spread throughout the building. Cricket is the result of several design goals, including user privacy, decentralized administration, network heterogeneity, and low cost. Rather than explicitly tracking user location, Cricket helps devices learn where they are and lets them decide whom to advertise this information to; it does not rely on any centralized management or control and there is no explicit coordination between beacons; it provides information to devices regardless of their type of network connectivity; and each Cricket device is made from off-the-shelf components and costs less than U.S. $10. We describe the randomized algorithm used by beacons to transmit information, the use of concurrent radio and ultrasonic signals to infer distance, the listener inference algorithms to overcome multipath and interference, and practical beacon configuration and positioning techniques that improve accuracy. Our experience with Cricket shows that several location-dependent applications such as in-building active maps and device control can be developed with little effort or manual configuration.
---
paper_title: Navitime: Supporting Pedestrian Navigation in the Real World

paper_content:

Almost 2 million Japanese citizens use Navitime, a mobile phone-based navigation service that incorporates various modes of transportation. User experiences reveal implications for designing urban-computing services. Location-based services are a key pervasive computing application that could deeply influence urban spaces and their inhabitants. Recent advances in mobile phones, GPS, and wireless networking infrastructures are making it possible to implement and operate large-scale location- based services in the real world.
---
paper_title: Melodious walkabout - implicit navigation with contextualized personal audio contents

paper_content:

In this paper the design, development and evaluation of a GPS-based auditory navigation system is presented that implicitly guides a user by a contextualized rendering of personal audio files. The benefit of this navigation system is that the user can listen to his own audio contents while being navigated. Wearing headphones, the user listens to audio contents which are located in a virtual environment. The user simply walks in the direction where the sound seems to have its origin. A formal evaluation under field conditions proved that navigation with contextualized audio contents is efficient and intuitive and that users are highly satisfied with the navigation support given by the evaluated auditory display.
---
paper_title: AudioGPS: Spatial Audio Navigation with a Minimal Attention Interface

paper_content:

Abstract: In this paper we describe a prototype spatial audio user interface for a Global Positioning System (GPS). The interface is designed to allow mobile users to carry out location tasks while their eyes, hands or attention are otherwise engaged. Audio user interfaces for GPS have typically been designed to meet the needs of visually impaired users, and generally, though not exclusively, employ speech-audio. In contrast, our prototype system uses a simple form of non-speech, spatial audio. This paper analyses various candidate audio mappings for location and distance information. A variety of tasks, design considerations, design trade-offs and opportunities are considered. The findings from pilot empirical testing are reported. Finally, opportunities for improvements to the system and for future evaluation are explored.
---
paper_title: A Self-Calibrating , Vision-Based Navigation Assistant

paper_content:

We describe a body-worn sensor suite, environment representation, set of algorithms, and graphical-aural interface designed to provide human-centered guidance to a person moving through a complex space. The central idea underlying our approach is to model the environment as a graph of visually distinctive places (graph nodes) connected by path segments (graph edges). During exploration, our algorithm processes multiple video-rate inputs to identify visual features and construct the “place graph” representation of the traversed space. The system then provides visual and/or spoken guidance in user-centered terms to lead the user along existing or newly-synthesized paths. Our approach is novel in several respects: it requires no precise calibration of the cameras or multi-camera rig used; it generalizes to any number of cameras with any placement on the body; it learns the correlation between user motion and evolution of image features; it constructs the place graph automatically; and it provides only coarse (rather than precise metrical) guidance to the user. We present an experimental study of our methods applied to walking routes through both indoor and outdoor environments, and show that the system provides accurate localization and effective navigation guidance.
---
paper_title: NAVIO ? A Navigation and Guidance Service for Pedestrians

paper_content:

In the research project NAVIO (Pedestrian Navigation Systems in Combined Indoor/Outdoor Environements) at our University we are working on the improvement of navigation services for pedestrians. Thereby we are mainly focusing on the information aspect of location-based services, i.e., on the user’s task at hand and the support of the user’s decisions by information provided by such a service. Specifications will allow us to select appropriate sensor data and to integrate data when and where needed, to propose context-dependent routes fitting to partly conflicting interests and goals as well as to select appropriate communication methods in terms of supporting the user guidance by various multimedia cartography forms. These taks are addressed in the project in three different work packages, i.e., the first on “Integrated positioning”, the second on “Pedestrian route modeling” and the third on “Multimedia route communication”. In this paper we will concentrate on the research work and findings in the first work package. For continuous positioning of a pedestrian suitable location technologies include GNSS and indoor location techniques, cellular phone positioning, dead reckoning sensors (e.g. magnetic compass, gyro and accelerometers) for measurement of heading and travelled distance as well as barometric pressure sensors for height determination. The integration of these sensors in a modern multi-sensor system can be performed using an adapted Kalman filter. To test and to demonstrate our approach, we take a use case scenario into account, i.e., the guidance of visitors to departments of the Vienna University of Technology. The results of simulation studies and practical tests could confirm that such a service can achieve a high level of performance for the guidance of a pedestrian in urban areas and mixed indoor and outdoor environments.
---
paper_title: Design and development of an indoor navigation and object identification system for the blind

paper_content:

In this paper we present a new system that assists blind users in orienting themselves in indoor environments. We developed a sensor module that can be handled like a flashlight by a blind user and can be used for searching tasks within the three-dimensional environment. By pressing keys, inquiries concerning object characteristics, position, orientation and navigation can be sent to a connected portable computer, or to a federation of data servers providing models of the environment. Finally these inquiries are acoustically answered over a text-to-speech engine.
---
paper_title: Location Systems for Ubiquitous Computing

paper_content:

This survey and taxonomy of location systems for mobile-computing applications describes a spectrum of current products and explores the latest in the field. To make sense of this domain, we have developed a taxonomy to help developers of location-aware applications better evaluate their options when choosing a location-sensing system. The taxonomy may also aid researchers in identifying opportunities for new location-sensing techniques.
---
paper_title: Making Sensor Networks Practical with Robots

paper_content:

While wireless sensor networks offer new capabilities, there are a number of issues that hinder their deployment in practice. We argue that robotics can solve or greatly reduce the impact of many of these issues. Our hypothesis has been tested in the context of an autonomous system to care for houseplants that we have deployed in our office environment. This paper describes what we believe is needed to make sensor networks practical, the role robots can play in accomplishing this, and the results we have obtained in developing our application.
---
paper_title: LaureaPOP indoor navigation service for the visually impaired in a WLAN environment

paper_content:

Many navigation systems for visually impaired people have been developed, but few can provide dynamic interactions and adaptability to changes. The aim of this working life project is to create an innovative navigation service solution that will improve the quality of life of the visually impaired. For example, a university campus might be such a large and rambling place that visually impaired people can not always find the services or rooms they want to. Therefore, we are devising new service solutions that exploit the technical features of modern WLAN systems in an innovative way. This paper describes the LaureaPOP system that focuses on the indoor navigation service design in a wireless local area network environment.
---
paper_title: RADAR: an in-building RF-based user location and tracking system

paper_content:

The proliferation of mobile computing devices and local-area wireless networks has fostered a growing interest in location-aware systems and services. In this paper we present RADAR, a radio-frequency (RF)-based system for locating and tracking users inside buildings. RADAR operates by recording and processing signal strength information at multiple base stations positioned to provide overlapping coverage in the area of interest. It combines empirical measurements with signal propagation modeling to determine user location and thereby enable location-aware services and applications. We present experimental results that demonstrate the ability of RADAR to estimate user location with a high degree of accuracy.
---
paper_title: Path Planning and Following Algorithms in an Indoor Navigation Model for Visually Impaired

paper_content:

This paper describes, path planning and following algorithms for use in indoor navigation for the blind and visually impaired. Providing indoor navigational assistance for this type of users presents additional challenges not faced by conventional guidance systems, due to the personal nature of the interactions. The algorithms are part of an overall Indoor Navigation Model that is used to provide assistance and guidance in unfamiliar indoor environments. Path planning uses the A* and Dijkstra's shortest path algorithms, to operate on an "Intelligent Map", that is based on a new data structure termed "cactus tree" which is predicated on the relationships between the different objects that represent an indoor environment. The paths produced are termed "virtual hand rails", which can be used to dynamically plan a path for a user within a region. The path following algorithm is based on dead reckoning, but incorporates human factors as well as information about the flooring and furnishing structures along the intended planned path. Experimental and simulating results show that the guiding/navigation problem becomes a divergent mathematical problem if the positional information offered by the positioning and tracking systems does not reach a certain requirement. This research explores the potential to design an application for the visually impaired even when to- date 'positioning and tracking' system cannot offer reliable position information that highly required by this type of application.
---
paper_title: A blind navigation system using RFID for indoor environments

paper_content:

A location and tracking system becomes very important to our future world of pervasive computing, where information is all around us. Location is one of the most needed information for emerging and future applications. Since the public use of GPS satellite is allowed, several state-of-the-art devices become part of our life, e.g. a car navigator and a mobile phone with a built-in GPS receiver. However, location information for indoor environments is still very limited. Several techniques are proposed to get location information in buildings such as using a radio signal triangulation, a radio signal (beacon) emitter, or signal fingerprinting. Using radio frequency identification (RFID) tags is a new way of giving location information to users. Due to its passive communication circuit, RFID tags can be embedded almost anywhere without an energy source. The tags stores location information and gives it to any reader that is within a proximity range which can be up to 10-15 meters for UHF RFID systems. We propose an RFID-based system for navigation in a building for blind people or visually impaired. The system relies on the location information on the tag, a userpsilas destination, and a routing server where the shortest route from the userpsilas current location to the destination. The navigation device communicates with the routing server using GPRS networks. We build a prototype based on our design and show some results. We found that there are some delay problems in the devices which are the communication delay due to the cold start cycle of a GPRS modem and the voice delay due to the file transfer delay from a MMC module.
---
paper_title: A space-identifying ubiquitous infrastructure and its application for tour-guiding service

paper_content:

In this paper, a novel tour-guiding system is introduced, based on our space-identifying ubiquitous infrastructure, where positioning devices are deployed ubiquitously to identify the place of users. In this infrastructure, we can flexibly construct information service related to the places of interest in the city by modeling the space of the real world as a set of relations among the discrete places, and attaching space-identifying devices to them. Our developed tour-guiding system introduces many art works in a large commercial complex in Japan. Based on the benefit of the infrastructure, this system can provide detailed navigation service as well as art introduction service in both indoor and outdoor environments, and can guide the users to reach their interested art works. Currently, this system is already used in practice for a commercial service. In this paper, the design of this system is described and its navigation capability is verified through a user test in the real environment to discuss the effectiveness of our approach.
---
paper_title: GongPath: Development of BIM Based Indoor Pedestrian Navigation System

paper_content:

This paper proposes a framework to enable intuitive navigation guidance for complex buildings which are huge in size and their space boundaries contain non-convex shape including non-navigable areas inside. Our approach utilizes ‘topological’ way-finding method to generate paths. This can be done by means of the integration of building information model (BIM) with our new algorithm to subdivide the spaces. The second main principle is to improve the visual information by using a new method to render all three dimensional views possibly observed in a building beforehand. This has been realized by imaging serviced using client-server architecture with supercomputer computation power.
---
paper_title: 3-D human navigation system considering various transition preferences

paper_content:

Walking is the most fundamental means of human transportation. Unlike travel by car, walking is not planar, but rather stereoscopic. We therefore developed a real navigation system for pedestrian point-to-point navigation. We propose herein a method of 3D pedestrian navigation, in which position detection is driven mainly by dead reckoning. The proposed method enables ubiquitous round-the-clock 3D positioning, even inside buildings or between tall buildings. In addition, pedestrian navigation is customized by changing the costs of the road network links. Finally, a positioning data accumulation system is implemented so that we can log tracks and easily incorporate new roads or attributes in the future.
---
paper_title: Robot-assisted wayfinding for the visually impaired in structured indoor environments

paper_content:

We present a robot-assisted wayfinding system for the visually impaired in structured indoor environments. The system consists of a mobile robotic guide and small passive RFID sensors embedded in the environment. The system is intended for use in indoor environments, such as office buildings, supermarkets and airports. We describe how the system was deployed in two indoor environments and evaluated by visually impaired participants in a series of pilot experiments. We analyze the system's successes and failures and outline our plans for future research and development.
---
paper_title: A resource-adaptive mobile navigation system

paper_content:

The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
---
paper_title: Drishti: an integrated navigation system for visually impaired and disabled

paper_content:

Drishti is a wireless pedestrian navigation system. It integrates several technologies including wearable computers, voice recognition and synthesis, wireless networks, Geographic Information System (GIS) and Global positioning system (GPS). Drishti augments contextual information to the visually impaired and computes optimized routes based on user preference, temporal constraints (e.g. traffic congestion), and dynamic obstacles (e.g. ongoing ground work, road blockade for special events). The system constantly guides the blind user to navigate based on static and dynamic data. Environmental conditions and landmark information queried from a spatial database along their route are provided on the fly through detailed explanatory voice cues. The system also provides capability for the user to add intelligence, as perceived by, the blind user, to the central server hosting the spatial database. Our system is supplementary to other navigational aids such as canes, blind guide dogs and wheel chairs.
---
paper_title: MOBIC: Designing a Travel Aid for Blind and Elderly People

paper_content:

This paper presents the research for the development of a new travel aid to increase the independent mobility of blind and elderly travellers. This aid will build on the technologies of geographical information systems (GIS) and the Global Positioning System (GPS). The MOBIC Travel Aid (MOTA) consists of two interrelated components : the MOBIC Pre-journey System (MOPS) to assist users in planning journeys and the MOBIC Outdoor System (MooDs) to execute these plans by providing users with orientation and navigation assistance during journeys. The MOBIC travel aid is complementary to primary mobility aids such as the long cane or guide dog. Results of a study of user requirements are presented and their implications for the initial design of the system are discussed.
---
paper_title: Semantically enriched navigation for indoor environments

paper_content:

Location-based mobile services have been in use, and studied, for a long time. With the proliferation of wireless networking technologies, users are mostly interested in advanced services that render the surrounding environment (i.e., the building) highly intelligent and significantly facilitate their activities. In this paper our focus is on indoor navigation, one of the most important location services. Existing approaches for indoor navigation are driven by geometric information and neglect important aspects, such as the semantics of space and user capabilities and context. The derived applications are not intelligent enough to catalytically contribute to the pervasive computing vision. In this paper, a novel navigation mechanism is introduced. Such navigation scheme is enriched with user profiles and the adoption of an ontological framework. These enhancements introduce a series of technical challenges that are extensively discussed throughout the paper.
---
paper_title: Learning Building Layouts with Non-Geometric Visual Information: The Effects of Visual Impairment and Age

paper_content:

Previous studies suggest that humans rely on geometric visual information (hallway structure) rather than non-geometric visual information (eg doors, signs, and lighting) for acquiring cognitive maps of novel indoor layouts. In this study we asked whether visual impairment and age affect reliance on non-geometric visual information for layout learning. We tested three groups of participants—younger (<50 years of age) normally sighted; older (50–70 years of age) normally sighted; and low-vision (people with heterogeneous forms of visual impairment ranging in age from 18 to 67 years). Participants learned target locations in building layouts using four presentation modes: a desktop virtual environment (VE) displaying only geometric cues (sparse VE); a VE displaying both geometric and non-geometric cues (photorealistic VE); a map; and a real building. Layout knowledge was assessed by map drawing and by asking participants to walk to specified targets in the real space. Results indicate that low-vision and ol...
---
paper_title: Steps Toward Accommodating Variable Position Tracking Accuracy in a Mobile Augmented Reality System

paper_content:

The position-tracking accuracy of a location-aware mobile system can change dynamically as a function of the user’s location and other variables specific to the tracker technology used. This is especially problematic for mobile augmented reality systems, which ideally require extremely precise position tracking for the user’s head, but which may not always be able to achieve the necessary level of accuracy. While it is possible to ignore variable positional accuracy in an augmented reality user interface, this can make for a confusing system; for example, when accuracy is low, virtual objects that are nominally registered with real ones may be too far off to be of use. To address this problem, we describe the early stages of an experimental mobile augmented reality system that adapts its user interface automatically to accommodate changes in tracking accuracy. Our system employs different technologies for tracking a user’s position, resulting in a wide variation in positional accuracy: an indoor ultrasonic tracker and an outdoor real-time kinematic GPS system. For areas outside the range of both, we introduce a dead-reckoning approach that combines a pedometer and orientation tracker with environmental knowledge expressed in spatial maps and accessibility graphs. We present preliminary results from this approach in the context of a navigational guidance system that helps users to orient themselves in an unfamiliar environment. Our system uses inferencing and path planning to guide users toward targets that they choose.
---
paper_title: CoINS: Context Sensitive Indoor Navigation System

paper_content:

The Context sensitive Indoor Navigation System (CoINS) implements an architecture to develop context-aware indoor user guidance services and applications. This paper presents a detailed discussion on algorithms and architectural issues in building an indoor guidance system. We first start with the World Model and required mapping to 2D for the process of path calculation and simplification. We also compare several algorithm optimizations applied in this particular context. The system provides the infrastructure to support different techniques of presenting the path and supporting user orientation to reach a certain destination in indoor premises.
---
paper_title: Navitime: Supporting Pedestrian Navigation in the Real World

paper_content:

Almost 2 million Japanese citizens use Navitime, a mobile phone-based navigation service that incorporates various modes of transportation. User experiences reveal implications for designing urban-computing services. Location-based services are a key pervasive computing application that could deeply influence urban spaces and their inhabitants. Recent advances in mobile phones, GPS, and wireless networking infrastructures are making it possible to implement and operate large-scale location- based services in the real world.
---
paper_title: A Self-Calibrating , Vision-Based Navigation Assistant

paper_content:

We describe a body-worn sensor suite, environment representation, set of algorithms, and graphical-aural interface designed to provide human-centered guidance to a person moving through a complex space. The central idea underlying our approach is to model the environment as a graph of visually distinctive places (graph nodes) connected by path segments (graph edges). During exploration, our algorithm processes multiple video-rate inputs to identify visual features and construct the “place graph” representation of the traversed space. The system then provides visual and/or spoken guidance in user-centered terms to lead the user along existing or newly-synthesized paths. Our approach is novel in several respects: it requires no precise calibration of the cameras or multi-camera rig used; it generalizes to any number of cameras with any placement on the body; it learns the correlation between user motion and evolution of image features; it constructs the place graph automatically; and it provides only coarse (rather than precise metrical) guidance to the user. We present an experimental study of our methods applied to walking routes through both indoor and outdoor environments, and show that the system provides accurate localization and effective navigation guidance.
---
paper_title: Path Planning and Following Algorithms in an Indoor Navigation Model for Visually Impaired

paper_content:

This paper describes, path planning and following algorithms for use in indoor navigation for the blind and visually impaired. Providing indoor navigational assistance for this type of users presents additional challenges not faced by conventional guidance systems, due to the personal nature of the interactions. The algorithms are part of an overall Indoor Navigation Model that is used to provide assistance and guidance in unfamiliar indoor environments. Path planning uses the A* and Dijkstra's shortest path algorithms, to operate on an "Intelligent Map", that is based on a new data structure termed "cactus tree" which is predicated on the relationships between the different objects that represent an indoor environment. The paths produced are termed "virtual hand rails", which can be used to dynamically plan a path for a user within a region. The path following algorithm is based on dead reckoning, but incorporates human factors as well as information about the flooring and furnishing structures along the intended planned path. Experimental and simulating results show that the guiding/navigation problem becomes a divergent mathematical problem if the positional information offered by the positioning and tracking systems does not reach a certain requirement. This research explores the potential to design an application for the visually impaired even when to- date 'positioning and tracking' system cannot offer reliable position information that highly required by this type of application.
---
paper_title: A space-identifying ubiquitous infrastructure and its application for tour-guiding service

paper_content:

In this paper, a novel tour-guiding system is introduced, based on our space-identifying ubiquitous infrastructure, where positioning devices are deployed ubiquitously to identify the place of users. In this infrastructure, we can flexibly construct information service related to the places of interest in the city by modeling the space of the real world as a set of relations among the discrete places, and attaching space-identifying devices to them. Our developed tour-guiding system introduces many art works in a large commercial complex in Japan. Based on the benefit of the infrastructure, this system can provide detailed navigation service as well as art introduction service in both indoor and outdoor environments, and can guide the users to reach their interested art works. Currently, this system is already used in practice for a commercial service. In this paper, the design of this system is described and its navigation capability is verified through a user test in the real environment to discuss the effectiveness of our approach.
---
paper_title: GongPath: Development of BIM Based Indoor Pedestrian Navigation System

paper_content:

This paper proposes a framework to enable intuitive navigation guidance for complex buildings which are huge in size and their space boundaries contain non-convex shape including non-navigable areas inside. Our approach utilizes ‘topological’ way-finding method to generate paths. This can be done by means of the integration of building information model (BIM) with our new algorithm to subdivide the spaces. The second main principle is to improve the visual information by using a new method to render all three dimensional views possibly observed in a building beforehand. This has been realized by imaging serviced using client-server architecture with supercomputer computation power.
---
paper_title: 3-D human navigation system considering various transition preferences

paper_content:

Walking is the most fundamental means of human transportation. Unlike travel by car, walking is not planar, but rather stereoscopic. We therefore developed a real navigation system for pedestrian point-to-point navigation. We propose herein a method of 3D pedestrian navigation, in which position detection is driven mainly by dead reckoning. The proposed method enables ubiquitous round-the-clock 3D positioning, even inside buildings or between tall buildings. In addition, pedestrian navigation is customized by changing the costs of the road network links. Finally, a positioning data accumulation system is implemented so that we can log tracks and easily incorporate new roads or attributes in the future.
---
paper_title: Robot-assisted wayfinding for the visually impaired in structured indoor environments

paper_content:

We present a robot-assisted wayfinding system for the visually impaired in structured indoor environments. The system consists of a mobile robotic guide and small passive RFID sensors embedded in the environment. The system is intended for use in indoor environments, such as office buildings, supermarkets and airports. We describe how the system was deployed in two indoor environments and evaluated by visually impaired participants in a series of pilot experiments. We analyze the system's successes and failures and outline our plans for future research and development.
---
paper_title: A resource-adaptive mobile navigation system

paper_content:

The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
---
paper_title: Drishti: an integrated navigation system for visually impaired and disabled

paper_content:

Drishti is a wireless pedestrian navigation system. It integrates several technologies including wearable computers, voice recognition and synthesis, wireless networks, Geographic Information System (GIS) and Global positioning system (GPS). Drishti augments contextual information to the visually impaired and computes optimized routes based on user preference, temporal constraints (e.g. traffic congestion), and dynamic obstacles (e.g. ongoing ground work, road blockade for special events). The system constantly guides the blind user to navigate based on static and dynamic data. Environmental conditions and landmark information queried from a spatial database along their route are provided on the fly through detailed explanatory voice cues. The system also provides capability for the user to add intelligence, as perceived by, the blind user, to the central server hosting the spatial database. Our system is supplementary to other navigational aids such as canes, blind guide dogs and wheel chairs.
---
paper_title: A wearable haptic navigation guidance system

paper_content:

This paper describes a wearable navigation system based on a haptic directional display embedded in the back of a vest. The system consists of a 4-by-4 array of micromotors for delivering haptic navigational signals to the user's back, an infrared-based input system for locating the user in an environment, and a wearable computer for route planning. User testing was conducted to evaluate the effectiveness of this system as a navigation guide for sighted users in an unfamiliar lab area. It is hoped that such a system can be a useful navigation guide for individuals with severe visual impairments in an unfamiliar environment. Future work will address the specific issues concerning blind navigation.
---
paper_title: Navigation System for the Blind: Auditory Display Modes and Guidance

paper_content:

The research we are reporting here is part of our effort to develop a navigation system for the blind. Our long-term goal is to create a portable, self-contained system that will allow visually impaired individuals to travel through familiar and unfamiliar environments without the assistance of guides. The system, as it exists now, consists of the following functional components: (1) a module for determining the traveler's position and orientation in space, (2) a Geographic Information System comprising a detailed database of our test site and software for route planning and for obtaining information from the database, and (3) the user interface. The experiment reported here is concerned with one function of the navigation system: guiding the traveler along a predefined route. We evaluate guidance performance as a function of four different display modes: one involving spatialized sound from a virtual acoustic display, and three involving verbal commands issued by a synthetic speech display. The virtual display mode fared best in terms of both guidance performance and user preferences.
---
paper_title: Virtual leading blocks for the deaf-blind: a real-time way-finder by verbal-nonverbal hybrid interface and high-density RFID tag space

paper_content:

In this paper, we discuss application possibilities of augmented reality technologies in the field of mobility support for the deaf blind. We propose the navigation system called virtual leading blocks for the deaf-blind, which consists of a wearable interface for Finger-Braille, one of the commonly used communication methods among deaf-blind people in Japan, and a ubiquitous environment for barrier-free application, which consists of floor-embedded active radio-frequency identification (RFID) tags. The wearable Finger-Braille interface using two Linux-based wristwatch computers has been developed as a hybrid interface of verbal and nonverbal communication in order to inform users of their direction and position through the tactile sensation. We propose the metaphor of "watermelon splitting" for navigation by this system and verify the feasibility of the proposed system through experiments.
---
paper_title: Design and development of an indoor navigation and object identification system for the blind

paper_content:

In this paper we present a new system that assists blind users in orienting themselves in indoor environments. We developed a sensor module that can be handled like a flashlight by a blind user and can be used for searching tasks within the three-dimensional environment. By pressing keys, inquiries concerning object characteristics, position, orientation and navigation can be sent to a connected portable computer, or to a federation of data servers providing models of the environment. Finally these inquiries are acoustically answered over a text-to-speech engine.
---
paper_title: MOBIC: Designing a Travel Aid for Blind and Elderly People

paper_content:

This paper presents the research for the development of a new travel aid to increase the independent mobility of blind and elderly travellers. This aid will build on the technologies of geographical information systems (GIS) and the Global Positioning System (GPS). The MOBIC Travel Aid (MOTA) consists of two interrelated components : the MOBIC Pre-journey System (MOPS) to assist users in planning journeys and the MOBIC Outdoor System (MooDs) to execute these plans by providing users with orientation and navigation assistance during journeys. The MOBIC travel aid is complementary to primary mobility aids such as the long cane or guide dog. Results of a study of user requirements are presented and their implications for the initial design of the system are discussed.
---
paper_title: Semantically enriched navigation for indoor environments

paper_content:

Location-based mobile services have been in use, and studied, for a long time. With the proliferation of wireless networking technologies, users are mostly interested in advanced services that render the surrounding environment (i.e., the building) highly intelligent and significantly facilitate their activities. In this paper our focus is on indoor navigation, one of the most important location services. Existing approaches for indoor navigation are driven by geometric information and neglect important aspects, such as the semantics of space and user capabilities and context. The derived applications are not intelligent enough to catalytically contribute to the pervasive computing vision. In this paper, a novel navigation mechanism is introduced. Such navigation scheme is enriched with user profiles and the adoption of an ontological framework. These enhancements introduce a series of technical challenges that are extensively discussed throughout the paper.
---
paper_title: Ultrasound-aided pedestrian dead reckoning for indoor navigation

paper_content:

Ad hoc solutions for tracking and providing navigation support to emergency response teams is an important and safety-critical challenge. We propose a navigation system based on a combination of foot-mounted inertial sensors and ultrasound beacons. We evaluate experimentally the performance of our dead reckoning system in different environments and for different trail topologies. The inherent drift observed in dead reckoning is addressed by deploying ultrasound beacons as landmarks. We study through simulations the use of the proposed approach in guiding a person along a defined path. ::: Simulation results show that satisfactory guidance performance is achieved despite noisy ultrasound measurements, magnetic interference and uncertainty in ultrasound node locations. The models used for the simulations are based on experimental data and the authors' experience with actual sensors. The simulation results will be used to inform future development of a full real time system.
---
paper_title: LaureaPOP indoor navigation service for the visually impaired in a WLAN environment

paper_content:

Many navigation systems for visually impaired people have been developed, but few can provide dynamic interactions and adaptability to changes. The aim of this working life project is to create an innovative navigation service solution that will improve the quality of life of the visually impaired. For example, a university campus might be such a large and rambling place that visually impaired people can not always find the services or rooms they want to. Therefore, we are devising new service solutions that exploit the technical features of modern WLAN systems in an innovative way. This paper describes the LaureaPOP system that focuses on the indoor navigation service design in a wireless local area network environment.
---
paper_title: Steps Toward Accommodating Variable Position Tracking Accuracy in a Mobile Augmented Reality System

paper_content:

The position-tracking accuracy of a location-aware mobile system can change dynamically as a function of the user’s location and other variables specific to the tracker technology used. This is especially problematic for mobile augmented reality systems, which ideally require extremely precise position tracking for the user’s head, but which may not always be able to achieve the necessary level of accuracy. While it is possible to ignore variable positional accuracy in an augmented reality user interface, this can make for a confusing system; for example, when accuracy is low, virtual objects that are nominally registered with real ones may be too far off to be of use. To address this problem, we describe the early stages of an experimental mobile augmented reality system that adapts its user interface automatically to accommodate changes in tracking accuracy. Our system employs different technologies for tracking a user’s position, resulting in a wide variation in positional accuracy: an indoor ultrasonic tracker and an outdoor real-time kinematic GPS system. For areas outside the range of both, we introduce a dead-reckoning approach that combines a pedometer and orientation tracker with environmental knowledge expressed in spatial maps and accessibility graphs. We present preliminary results from this approach in the context of a navigational guidance system that helps users to orient themselves in an unfamiliar environment. Our system uses inferencing and path planning to guide users toward targets that they choose.
---
paper_title: CoINS: Context Sensitive Indoor Navigation System

paper_content:

The Context sensitive Indoor Navigation System (CoINS) implements an architecture to develop context-aware indoor user guidance services and applications. This paper presents a detailed discussion on algorithms and architectural issues in building an indoor guidance system. We first start with the World Model and required mapping to 2D for the process of path calculation and simplification. We also compare several algorithm optimizations applied in this particular context. The system provides the infrastructure to support different techniques of presenting the path and supporting user orientation to reach a certain destination in indoor premises.
---
paper_title: Investigating the effectiveness of tactile feedback for mobile touchscreens

paper_content:

This paper presents a study of finger-based text entry for mobile devices with touchscreens. Many devices are now coming to market that have no physical keyboards (the Apple iPhone being a very popular example). Touchscreen keyboards lack any tactile feedback and this may cause problems for entering text and phone numbers. We ran an experiment to compare devices with a physical keyboard, a standard touchscreen and a touchscreen with tactile feedback added. We tested this in both static and mobile environments. The results showed that the addition of tactile feedback to the touchscreen significantly improved finger-based text entry, bringing it close to the performance of a real physical keyboard. A second experiment showed that higher specification tactile actuators could improve performance even further. The results suggest that manufacturers should use tactile feedback in their touchscreen devices to regain some of the feeling lost when interacting on a touchscreen with a finger.
---
paper_title: A resource-adaptive mobile navigation system

paper_content:

The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
---
paper_title: A wearable haptic navigation guidance system

paper_content:

This paper describes a wearable navigation system based on a haptic directional display embedded in the back of a vest. The system consists of a 4-by-4 array of micromotors for delivering haptic navigational signals to the user's back, an infrared-based input system for locating the user in an environment, and a wearable computer for route planning. User testing was conducted to evaluate the effectiveness of this system as a navigation guide for sighted users in an unfamiliar lab area. It is hoped that such a system can be a useful navigation guide for individuals with severe visual impairments in an unfamiliar environment. Future work will address the specific issues concerning blind navigation.
---
paper_title: A context aware handheld wayfinding system for individuals with cognitive impairments

paper_content:

A challenge to individuals with cognitive impairments in wayfinding is how to remain oriented, recall routines, and travel in unfamiliar areas in a way relying on limited cognitive capacity. According to psychological model of spatial navigation and the requirements of rehabilitation professionals, a novel wayfinding system is presented with an aim to increase workplace and life independence for people suffering from diseases such as traumatic brain injury, cerebral palsy, mental retardation, schizophrenia, Down syndromes, and Alzheimer's disease. This paper describes an approach to providing distributed cognition support of travel guidance for persons with cognitive disabilities. The unique strength of the system is the ability to provide unique-to-the-user prompts that are triggered by context. As this population is very sensitive to issues of abstraction (e.g. icons) and presents the designer with the need to tailor prompts to a 'universe-of-one' the use of images specific to each user and context is implemented. The key to the approach is to spread the context awareness across the system, with the context being flagged by the QR-code tags and the appropriate response being evoked by displaying the appropriate path guidance images indexed by the intersection of specific end-user and context ID embedded in the tags. By separating the context trigger from the pictorial response, responses can be updated independently of the rest of the installed system, and a single QR-code tag can trigger multiple responses in the PDA depending on the end-user and their specific path. A prototype is built and tested in field experiments with real patients. The experimental results show the human-computer interface is friendly and the capabilities of wayfinding are reliable.
---
paper_title: Tactile Wayfinder : A Non-Visual Support System for Wayfinding

paper_content:

Digital maps and route descriptions on a PDA have become very popular for navigation, not the least with the advent of the iPhone and its Google Maps application. A visual support for wayfinding, however, is not reasonable or even possible all the time. A pedestrian must pay attention to traffic on the street, a hiker should concentrate on the narrow trail, and a blind person relies on other modalities to find her way. To overcome these limitations, we developed a non-visual support for wayfinding that guides and keeps a mobile user en route by a tactile display. We designed a belt with vibrators that indicates directions and deviations from the path in an accurate and unobtrusive way. Our first user evaluation showed that on an open field without any landmarks the participants stayed well to given test routes and that wayfinding support is possible with our Tactile Wayfinder.
---
paper_title: LaureaPOP indoor navigation service for the visually impaired in a WLAN environment

paper_content:

Many navigation systems for visually impaired people have been developed, but few can provide dynamic interactions and adaptability to changes. The aim of this working life project is to create an innovative navigation service solution that will improve the quality of life of the visually impaired. For example, a university campus might be such a large and rambling place that visually impaired people can not always find the services or rooms they want to. Therefore, we are devising new service solutions that exploit the technical features of modern WLAN systems in an innovative way. This paper describes the LaureaPOP system that focuses on the indoor navigation service design in a wireless local area network environment.
---
paper_title: A Self-Calibrating , Vision-Based Navigation Assistant

paper_content:

We describe a body-worn sensor suite, environment representation, set of algorithms, and graphical-aural interface designed to provide human-centered guidance to a person moving through a complex space. The central idea underlying our approach is to model the environment as a graph of visually distinctive places (graph nodes) connected by path segments (graph edges). During exploration, our algorithm processes multiple video-rate inputs to identify visual features and construct the “place graph” representation of the traversed space. The system then provides visual and/or spoken guidance in user-centered terms to lead the user along existing or newly-synthesized paths. Our approach is novel in several respects: it requires no precise calibration of the cameras or multi-camera rig used; it generalizes to any number of cameras with any placement on the body; it learns the correlation between user motion and evolution of image features; it constructs the place graph automatically; and it provides only coarse (rather than precise metrical) guidance to the user. We present an experimental study of our methods applied to walking routes through both indoor and outdoor environments, and show that the system provides accurate localization and effective navigation guidance.
---
paper_title: Metronaut: a wearable computer with sensing and global communication capabilities

paper_content:

Metronaut is a novel wearable computer which captures information, senses position, provides wide range communications, consumes less than one watt of power, and weighs less than one pound. Metronaut employs a bar code reader for information input and position location, a two-way pager for communications, and an ARM processor for computation. Metronaut's application is schedule negotiation and guidance instructions for a visitor to the CMU campus. The visitor's position is determined from reading bar codes at information signs around campus. Modifications to the schedule are negotiated using the two-way pager for communications with the campus computing infrastructure. Metronaut is alternatively powered by a mechanical flywheel converting kinetic energy to electrical energy.
---
paper_title: A blind navigation system using RFID for indoor environments

paper_content:

A location and tracking system becomes very important to our future world of pervasive computing, where information is all around us. Location is one of the most needed information for emerging and future applications. Since the public use of GPS satellite is allowed, several state-of-the-art devices become part of our life, e.g. a car navigator and a mobile phone with a built-in GPS receiver. However, location information for indoor environments is still very limited. Several techniques are proposed to get location information in buildings such as using a radio signal triangulation, a radio signal (beacon) emitter, or signal fingerprinting. Using radio frequency identification (RFID) tags is a new way of giving location information to users. Due to its passive communication circuit, RFID tags can be embedded almost anywhere without an energy source. The tags stores location information and gives it to any reader that is within a proximity range which can be up to 10-15 meters for UHF RFID systems. We propose an RFID-based system for navigation in a building for blind people or visually impaired. The system relies on the location information on the tag, a userpsilas destination, and a routing server where the shortest route from the userpsilas current location to the destination. The navigation device communicates with the routing server using GPRS networks. We build a prototype based on our design and show some results. We found that there are some delay problems in the devices which are the communication delay due to the cold start cycle of a GPRS modem and the voice delay due to the file transfer delay from a MMC module.
---
paper_title: Portable traveling support system using image processing for the visually impaired

paper_content:

We have previously proposed a portable navigation system for the visually impaired (see Nakamura, K. et al., IEICE Trans. of Japan, vol.J79, p.1610-18, 1996; Takuno, S. et al., IEICE Trans. of Japan, vol.J83, p.293-302, 2000). However, there are some places where this system is unable to provide proper guidance. Since the traveling direction of the traveler in this system is measured by a terrestrial magnetism sensor, there is a possibility that the wrong direction is measured, due to the distortion of the terrestrial magnetism by vehicles, etc. Road markings, e.g., pedestrian crossing, white line of the road, are reliable information to measure the correct direction. Furthermore, street landmarks, e.g., electric pole, traffic-control sign and post box, are also useful for a traveler to confirm his position. Therefore, we have now adequately applied image processing to our portable navigation system to make it more reliable.
---
paper_title: A space-identifying ubiquitous infrastructure and its application for tour-guiding service

paper_content:

In this paper, a novel tour-guiding system is introduced, based on our space-identifying ubiquitous infrastructure, where positioning devices are deployed ubiquitously to identify the place of users. In this infrastructure, we can flexibly construct information service related to the places of interest in the city by modeling the space of the real world as a set of relations among the discrete places, and attaching space-identifying devices to them. Our developed tour-guiding system introduces many art works in a large commercial complex in Japan. Based on the benefit of the infrastructure, this system can provide detailed navigation service as well as art introduction service in both indoor and outdoor environments, and can guide the users to reach their interested art works. Currently, this system is already used in practice for a commercial service. In this paper, the design of this system is described and its navigation capability is verified through a user test in the real environment to discuss the effectiveness of our approach.
---
paper_title: GongPath: Development of BIM Based Indoor Pedestrian Navigation System

paper_content:

This paper proposes a framework to enable intuitive navigation guidance for complex buildings which are huge in size and their space boundaries contain non-convex shape including non-navigable areas inside. Our approach utilizes ‘topological’ way-finding method to generate paths. This can be done by means of the integration of building information model (BIM) with our new algorithm to subdivide the spaces. The second main principle is to improve the visual information by using a new method to render all three dimensional views possibly observed in a building beforehand. This has been realized by imaging serviced using client-server architecture with supercomputer computation power.
---
paper_title: Robot-assisted wayfinding for the visually impaired in structured indoor environments

paper_content:

We present a robot-assisted wayfinding system for the visually impaired in structured indoor environments. The system consists of a mobile robotic guide and small passive RFID sensors embedded in the environment. The system is intended for use in indoor environments, such as office buildings, supermarkets and airports. We describe how the system was deployed in two indoor environments and evaluated by visually impaired participants in a series of pilot experiments. We analyze the system's successes and failures and outline our plans for future research and development.
---
paper_title: A resource-adaptive mobile navigation system

paper_content:

The design of mobile navigation systems adapting to limited resources will be an important future challenge. Since typically several different means of transportation have to be combined in order to reach a destination, the user interface of such a system has to adapt to the user's changing situation. This applies especially to the alternating use of different technologies to detect the user's position, which should be as seamless as possible. This article presents a hybrid navigation system that relies on different technologies to determine the user's location and that adapts the presentation of route directions to the limited technical resources of the output device and the limited cognitive resources of the user.
---
paper_title: Drishti: an integrated navigation system for visually impaired and disabled

paper_content:

Drishti is a wireless pedestrian navigation system. It integrates several technologies including wearable computers, voice recognition and synthesis, wireless networks, Geographic Information System (GIS) and Global positioning system (GPS). Drishti augments contextual information to the visually impaired and computes optimized routes based on user preference, temporal constraints (e.g. traffic congestion), and dynamic obstacles (e.g. ongoing ground work, road blockade for special events). The system constantly guides the blind user to navigate based on static and dynamic data. Environmental conditions and landmark information queried from a spatial database along their route are provided on the fly through detailed explanatory voice cues. The system also provides capability for the user to add intelligence, as perceived by, the blind user, to the central server hosting the spatial database. Our system is supplementary to other navigational aids such as canes, blind guide dogs and wheel chairs.
---
paper_title: A wearable haptic navigation guidance system

paper_content:

This paper describes a wearable navigation system based on a haptic directional display embedded in the back of a vest. The system consists of a 4-by-4 array of micromotors for delivering haptic navigational signals to the user's back, an infrared-based input system for locating the user in an environment, and a wearable computer for route planning. User testing was conducted to evaluate the effectiveness of this system as a navigation guide for sighted users in an unfamiliar lab area. It is hoped that such a system can be a useful navigation guide for individuals with severe visual impairments in an unfamiliar environment. Future work will address the specific issues concerning blind navigation.
---
paper_title: Personal guidance system for the visually impaired

paper_content:

We outline the design for a navigation system for the visually impaired and describe the progress we have made toward such a system. Our long-term goal is for a portable, self-contained system that will allow visually impaired individuals to travel through familiar and unfamiliar environments without the assistance of guides. The system, as it exists now, consists of the following functional components: (1) a means of determining the traveler's position and orientation in space, (2) a Geographic Information System comprising a detailed database of the surrounding environment and functions for automatic route planning and for selecting the database information desired by the user, and (3) the user interface.
---
paper_title: Virtual leading blocks for the deaf-blind: a real-time way-finder by verbal-nonverbal hybrid interface and high-density RFID tag space

paper_content:

In this paper, we discuss application possibilities of augmented reality technologies in the field of mobility support for the deaf blind. We propose the navigation system called virtual leading blocks for the deaf-blind, which consists of a wearable interface for Finger-Braille, one of the commonly used communication methods among deaf-blind people in Japan, and a ubiquitous environment for barrier-free application, which consists of floor-embedded active radio-frequency identification (RFID) tags. The wearable Finger-Braille interface using two Linux-based wristwatch computers has been developed as a hybrid interface of verbal and nonverbal communication in order to inform users of their direction and position through the tactile sensation. We propose the metaphor of "watermelon splitting" for navigation by this system and verify the feasibility of the proposed system through experiments.
---
paper_title: Design and development of an indoor navigation and object identification system for the blind

paper_content:

In this paper we present a new system that assists blind users in orienting themselves in indoor environments. We developed a sensor module that can be handled like a flashlight by a blind user and can be used for searching tasks within the three-dimensional environment. By pressing keys, inquiries concerning object characteristics, position, orientation and navigation can be sent to a connected portable computer, or to a federation of data servers providing models of the environment. Finally these inquiries are acoustically answered over a text-to-speech engine.
---
paper_title: MOBIC: Designing a Travel Aid for Blind and Elderly People

paper_content:

This paper presents the research for the development of a new travel aid to increase the independent mobility of blind and elderly travellers. This aid will build on the technologies of geographical information systems (GIS) and the Global Positioning System (GPS). The MOBIC Travel Aid (MOTA) consists of two interrelated components : the MOBIC Pre-journey System (MOPS) to assist users in planning journeys and the MOBIC Outdoor System (MooDs) to execute these plans by providing users with orientation and navigation assistance during journeys. The MOBIC travel aid is complementary to primary mobility aids such as the long cane or guide dog. Results of a study of user requirements are presented and their implications for the initial design of the system are discussed.
---
paper_title: A walking navigation system for the blind

paper_content:

This paper proposes a walking navigation system for the blind. The system is based on a comparison of data obtained by a pedometer and a terrestrial magnetic sensor and prearranged teaching data of a route to a destination. The system gives an appropriate instruction (using voice and buzzer sound) during a user's walk. This paper mainly describes experiments designed to clarify the characteristics of the system. The results show that the nodes of a walking route for teaching should be less than 50 m, since the maximum error of the system is about 10% in a walking distance of 50 m. The experiments also show that the walkers (sighted men with eye masks) were guided by the system along a course of about 900 m, taking about 40 to 50 mins. © 1998 Scripta Technica. Syst Comp Jpn, 28(13): 36–45, 1997
---
paper_title: Ultrasound-aided pedestrian dead reckoning for indoor navigation

paper_content:

Ad hoc solutions for tracking and providing navigation support to emergency response teams is an important and safety-critical challenge. We propose a navigation system based on a combination of foot-mounted inertial sensors and ultrasound beacons. We evaluate experimentally the performance of our dead reckoning system in different environments and for different trail topologies. The inherent drift observed in dead reckoning is addressed by deploying ultrasound beacons as landmarks. We study through simulations the use of the proposed approach in guiding a person along a defined path. ::: Simulation results show that satisfactory guidance performance is achieved despite noisy ultrasound measurements, magnetic interference and uncertainty in ultrasound node locations. The models used for the simulations are based on experimental data and the authors' experience with actual sensors. The simulation results will be used to inform future development of a full real time system.
---
paper_title: Mobile Navigation Guide for the Visually Disabled

paper_content:

A location-aware navigation system has been developed and implemented for the visually disabled or visually impaired; the system is designed to improve individuals' independent mobility. This self-contained, portable system integrates several technologies, including mobile personal digital assistants, voice synthesis, a geographic information system (GIS), and a differential Global Positioning System (DGPS). The system is meant to augment the various sensory inputs available to the visually impaired user. It provides the user with navigation assistance, making use of voice cues iterating contextual building and feature information at regular intervals, through automatic GPS readings and a GIS database. To improve the efficiency of the retrieval of contextual information, an indexing method based on road segmentation was developed to replace the exhaustive search method. Experimental results show that the performance of the system on searching the buildings, landmarks, and other features around a road has been significantly improved by using this indexing method.
---
paper_title: A context aware handheld wayfinding system for individuals with cognitive impairments

paper_content:

A challenge to individuals with cognitive impairments in wayfinding is how to remain oriented, recall routines, and travel in unfamiliar areas in a way relying on limited cognitive capacity. According to psychological model of spatial navigation and the requirements of rehabilitation professionals, a novel wayfinding system is presented with an aim to increase workplace and life independence for people suffering from diseases such as traumatic brain injury, cerebral palsy, mental retardation, schizophrenia, Down syndromes, and Alzheimer's disease. This paper describes an approach to providing distributed cognition support of travel guidance for persons with cognitive disabilities. The unique strength of the system is the ability to provide unique-to-the-user prompts that are triggered by context. As this population is very sensitive to issues of abstraction (e.g. icons) and presents the designer with the need to tailor prompts to a 'universe-of-one' the use of images specific to each user and context is implemented. The key to the approach is to spread the context awareness across the system, with the context being flagged by the QR-code tags and the appropriate response being evoked by displaying the appropriate path guidance images indexed by the intersection of specific end-user and context ID embedded in the tags. By separating the context trigger from the pictorial response, responses can be updated independently of the rest of the installed system, and a single QR-code tag can trigger multiple responses in the PDA depending on the end-user and their specific path. A prototype is built and tested in field experiments with real patients. The experimental results show the human-computer interface is friendly and the capabilities of wayfinding are reliable.
---
paper_title: Tactile Wayfinder : A Non-Visual Support System for Wayfinding

paper_content:

Digital maps and route descriptions on a PDA have become very popular for navigation, not the least with the advent of the iPhone and its Google Maps application. A visual support for wayfinding, however, is not reasonable or even possible all the time. A pedestrian must pay attention to traffic on the street, a hiker should concentrate on the narrow trail, and a blind person relies on other modalities to find her way. To overcome these limitations, we developed a non-visual support for wayfinding that guides and keeps a mobile user en route by a tactile display. We designed a belt with vibrators that indicates directions and deviations from the path in an accurate and unobtrusive way. Our first user evaluation showed that on an open field without any landmarks the participants stayed well to given test routes and that wayfinding support is possible with our Tactile Wayfinder.
---
paper_title: LaureaPOP indoor navigation service for the visually impaired in a WLAN environment

paper_content:

Many navigation systems for visually impaired people have been developed, but few can provide dynamic interactions and adaptability to changes. The aim of this working life project is to create an innovative navigation service solution that will improve the quality of life of the visually impaired. For example, a university campus might be such a large and rambling place that visually impaired people can not always find the services or rooms they want to. Therefore, we are devising new service solutions that exploit the technical features of modern WLAN systems in an innovative way. This paper describes the LaureaPOP system that focuses on the indoor navigation service design in a wireless local area network environment.
---
paper_title: Steps Toward Accommodating Variable Position Tracking Accuracy in a Mobile Augmented Reality System

paper_content:

The position-tracking accuracy of a location-aware mobile system can change dynamically as a function of the user’s location and other variables specific to the tracker technology used. This is especially problematic for mobile augmented reality systems, which ideally require extremely precise position tracking for the user’s head, but which may not always be able to achieve the necessary level of accuracy. While it is possible to ignore variable positional accuracy in an augmented reality user interface, this can make for a confusing system; for example, when accuracy is low, virtual objects that are nominally registered with real ones may be too far off to be of use. To address this problem, we describe the early stages of an experimental mobile augmented reality system that adapts its user interface automatically to accommodate changes in tracking accuracy. Our system employs different technologies for tracking a user’s position, resulting in a wide variation in positional accuracy: an indoor ultrasonic tracker and an outdoor real-time kinematic GPS system. For areas outside the range of both, we introduce a dead-reckoning approach that combines a pedometer and orientation tracker with environmental knowledge expressed in spatial maps and accessibility graphs. We present preliminary results from this approach in the context of a navigational guidance system that helps users to orient themselves in an unfamiliar environment. Our system uses inferencing and path planning to guide users toward targets that they choose.
---
paper_title: Navitime: Supporting Pedestrian Navigation in the Real World

paper_content:

Almost 2 million Japanese citizens use Navitime, a mobile phone-based navigation service that incorporates various modes of transportation. User experiences reveal implications for designing urban-computing services. Location-based services are a key pervasive computing application that could deeply influence urban spaces and their inhabitants. Recent advances in mobile phones, GPS, and wireless networking infrastructures are making it possible to implement and operate large-scale location- based services in the real world.
---
paper_title: Melodious walkabout - implicit navigation with contextualized personal audio contents

paper_content:

In this paper the design, development and evaluation of a GPS-based auditory navigation system is presented that implicitly guides a user by a contextualized rendering of personal audio files. The benefit of this navigation system is that the user can listen to his own audio contents while being navigated. Wearing headphones, the user listens to audio contents which are located in a virtual environment. The user simply walks in the direction where the sound seems to have its origin. A formal evaluation under field conditions proved that navigation with contextualized audio contents is efficient and intuitive and that users are highly satisfied with the navigation support given by the evaluated auditory display.
---
paper_title: AudioGPS: Spatial Audio Navigation with a Minimal Attention Interface

paper_content:

Abstract: In this paper we describe a prototype spatial audio user interface for a Global Positioning System (GPS). The interface is designed to allow mobile users to carry out location tasks while their eyes, hands or attention are otherwise engaged. Audio user interfaces for GPS have typically been designed to meet the needs of visually impaired users, and generally, though not exclusively, employ speech-audio. In contrast, our prototype system uses a simple form of non-speech, spatial audio. This paper analyses various candidate audio mappings for location and distance information. A variety of tasks, design considerations, design trade-offs and opportunities are considered. The findings from pilot empirical testing are reported. Finally, opportunities for improvements to the system and for future evaluation are explored.
---
paper_title: A Self-Calibrating , Vision-Based Navigation Assistant

paper_content:

We describe a body-worn sensor suite, environment representation, set of algorithms, and graphical-aural interface designed to provide human-centered guidance to a person moving through a complex space. The central idea underlying our approach is to model the environment as a graph of visually distinctive places (graph nodes) connected by path segments (graph edges). During exploration, our algorithm processes multiple video-rate inputs to identify visual features and construct the “place graph” representation of the traversed space. The system then provides visual and/or spoken guidance in user-centered terms to lead the user along existing or newly-synthesized paths. Our approach is novel in several respects: it requires no precise calibration of the cameras or multi-camera rig used; it generalizes to any number of cameras with any placement on the body; it learns the correlation between user motion and evolution of image features; it constructs the place graph automatically; and it provides only coarse (rather than precise metrical) guidance to the user. We present an experimental study of our methods applied to walking routes through both indoor and outdoor environments, and show that the system provides accurate localization and effective navigation guidance.
---
paper_title: Robot-assisted wayfinding for the visually impaired in structured indoor environments

paper_content:

We present a robot-assisted wayfinding system for the visually impaired in structured indoor environments. The system consists of a mobile robotic guide and small passive RFID sensors embedded in the environment. The system is intended for use in indoor environments, such as office buildings, supermarkets and airports. We describe how the system was deployed in two indoor environments and evaluated by visually impaired participants in a series of pilot experiments. We analyze the system's successes and failures and outline our plans for future research and development.
---
paper_title: Navigation System for the Blind: Auditory Display Modes and Guidance

paper_content:

The research we are reporting here is part of our effort to develop a navigation system for the blind. Our long-term goal is to create a portable, self-contained system that will allow visually impaired individuals to travel through familiar and unfamiliar environments without the assistance of guides. The system, as it exists now, consists of the following functional components: (1) a module for determining the traveler's position and orientation in space, (2) a Geographic Information System comprising a detailed database of our test site and software for route planning and for obtaining information from the database, and (3) the user interface. The experiment reported here is concerned with one function of the navigation system: guiding the traveler along a predefined route. We evaluate guidance performance as a function of four different display modes: one involving spatialized sound from a virtual acoustic display, and three involving verbal commands issued by a synthetic speech display. The virtual display mode fared best in terms of both guidance performance and user preferences.
---
paper_title: MOBIC: Designing a Travel Aid for Blind and Elderly People

paper_content:

This paper presents the research for the development of a new travel aid to increase the independent mobility of blind and elderly travellers. This aid will build on the technologies of geographical information systems (GIS) and the Global Positioning System (GPS). The MOBIC Travel Aid (MOTA) consists of two interrelated components : the MOBIC Pre-journey System (MOPS) to assist users in planning journeys and the MOBIC Outdoor System (MooDs) to execute these plans by providing users with orientation and navigation assistance during journeys. The MOBIC travel aid is complementary to primary mobility aids such as the long cane or guide dog. Results of a study of user requirements are presented and their implications for the initial design of the system are discussed.
---
paper_title: A walking navigation system for the blind

paper_content:

This paper proposes a walking navigation system for the blind. The system is based on a comparison of data obtained by a pedometer and a terrestrial magnetic sensor and prearranged teaching data of a route to a destination. The system gives an appropriate instruction (using voice and buzzer sound) during a user's walk. This paper mainly describes experiments designed to clarify the characteristics of the system. The results show that the nodes of a walking route for teaching should be less than 50 m, since the maximum error of the system is about 10% in a walking distance of 50 m. The experiments also show that the walkers (sighted men with eye masks) were guided by the system along a course of about 900 m, taking about 40 to 50 mins. © 1998 Scripta Technica. Syst Comp Jpn, 28(13): 36–45, 1997
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paper_title: Mobile Navigation Guide for the Visually Disabled

paper_content:

A location-aware navigation system has been developed and implemented for the visually disabled or visually impaired; the system is designed to improve individuals' independent mobility. This self-contained, portable system integrates several technologies, including mobile personal digital assistants, voice synthesis, a geographic information system (GIS), and a differential Global Positioning System (DGPS). The system is meant to augment the various sensory inputs available to the visually impaired user. It provides the user with navigation assistance, making use of voice cues iterating contextual building and feature information at regular intervals, through automatic GPS readings and a GIS database. To improve the efficiency of the retrieval of contextual information, an indexing method based on road segmentation was developed to replace the exhaustive search method. Experimental results show that the performance of the system on searching the buildings, landmarks, and other features around a road has been significantly improved by using this indexing method.
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paper_title: Navitime: Supporting Pedestrian Navigation in the Real World

paper_content:

Almost 2 million Japanese citizens use Navitime, a mobile phone-based navigation service that incorporates various modes of transportation. User experiences reveal implications for designing urban-computing services. Location-based services are a key pervasive computing application that could deeply influence urban spaces and their inhabitants. Recent advances in mobile phones, GPS, and wireless networking infrastructures are making it possible to implement and operate large-scale location- based services in the real world.
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Title: Indoor Human Navigation Systems: A Survey

Section 1: Introduction
Description 1: Write an introduction to human navigation skills, how they are used in both indoor and outdoor environments, and the importance and challenges of indoor navigation systems.

Section 2: Localization
Description 2: Discuss various techniques for determining a user's position and orientation, including dead-reckoning, direct sensing, triangulation, and pattern recognition.

Section 3: Dead-Reckoning
Description 3: Provide details on dead-reckoning localization techniques and their reliance on odometry readings from various sensors.

Section 4: Direct Sensing
Description 4: Describe direct sensing localization methods and technologies such as RFID, Infrared, Ultrasound, Bluetooth, and Barcodes.

Section 5: Triangulation
Description 5: Explain triangulation-based localization methods, including lateration and angulation, and their use of known reference points.

Section 6: Pattern Recognition
Description 6: Discuss pattern recognition-based localization methods that use sensor data and environmental maps for determining user positions.

Section 7: Path Planning
Description 7: Cover strategies for path planning in navigation systems, considerations for user requirements, different algorithms, and graph-based versus grid-based approaches.

Section 8: Representation
Description 8: Discuss the importance of storing and retrieving information for indoor navigation, the types of maps used, and potential challenges.

Section 9: Interaction
Description 9: Outline various forms of user interaction, including visual, audio, and haptic feedback, and discuss design challenges and considerations.

Section 10: System Feedback
Description 10: Explain the different techniques for providing directions to the user, such as visual displays, audio feedback, and haptic interactions.

Section 11: User Input
Description 11: Describe methods of user input for navigation systems, including traditional input methods and speech recognition.

Section 12: Research Issues
Description 12: Identify and elaborate on various research issues and open questions within the field of indoor navigation systems.

Section 13: Conclusion
Description 13: Summarize the main points of the paper, highlighting the state of current technologies and potential areas for future research.