Custom IMU-Based Wearable System for Robust 2.4 GHz Wireless Human Body
  Parts Orientation Tracking and 3D Movement Visualization on an Avatar
Javier González-Alonso David Oviedo-Pastor Héctor J. Aguado Francisco J. Díaz-Pernas David González-Ortega Mario Martínez-Zarzuela
Recent studies confirm the applicability of Inertial Measurement Unit
(IMU)-based systems for human motion analysis. Notwithstanding, high-end
IMU-based commercial solutions are yet too expensive and complex to democratize
their use among a wide range of potential users. Less featured entry-level
commercial solutions are being introduced in the market, trying to fill this
gap, but still present some limitations that need to be overcome. At the same
time, there is a growing number of scientific papers using not commercial, but
custom do-it-yourself IMU-based systems in medical and sports applications.
Even though these solutions can help to popularize the use of this technology,
they have more limited features and the description on how to design and build
them from scratch is yet too scarce in the literature. The aim of this work is
two-fold: (1) Proving the feasibility of building an affordable custom solution
aimed at simultaneous multiple body parts orientation tracking; while providing
a detailed bottom-up description of the required hardware, tools, and
mathematical operations to estimate and represent 3D movement in real-time. (2)
Showing how the introduction of a custom 2.4 GHz communication protocol
including a channel hopping strategy can address some of the current
communication limitations of entry-level commercial solutions. The proposed
system can be used for wireless real-time human body parts orientation tracking
with up to 10 custom sensors, at least at 50 Hz. In addition, it provides a
more reliable motion data acquisition in Bluetooth and Wi-Fi crowded
environments, where the use of entry-level commercial solutions might be
unfeasible. This system can be used as a groundwork for developing affordable
human motion analysis solutions that do not require an accurate kinematic
analysis.