Robot Localization and Mapping Final Report -- Sequential Adversarial
  Learning for Self-Supervised Deep Visual Odometry
Akankshya Kar Sajal Maheshwari Shamit Lal Vinay Sameer Raja Kad
Visual odometry (VO) and SLAM have been using multi-view geometry via local
structure from motion for decades. These methods have a slight disadvantage in
challenging scenarios such as low-texture images, dynamic scenarios, etc.
Meanwhile, use of deep neural networks to extract high level features is
ubiquitous in computer vision. For VO, we can use these deep networks to
extract depth and pose estimates using these high level features. The visual
odometry task then can be modeled as an image generation task where the pose
estimation is the by-product. This can also be achieved in a self-supervised
manner, thereby eliminating the data (supervised) intensive nature of training
deep neural networks. Although some works tried the similar approach [1], the
depth and pose estimation in the previous works are vague sometimes resulting
in accumulation of error (drift) along the trajectory. The goal of this work is
to tackle these limitations of past approaches and to develop a method that can
provide better depths and pose estimates. To address this, a couple of
approaches are explored: 1) Modeling: Using optical flow and recurrent neural
networks (RNN) in order to exploit spatio-temporal correlations which can
provide more information to estimate depth. 2) Loss function: Generative
adversarial network (GAN) [2] is deployed to improve the depth estimation (and
thereby pose too), as shown in Figure 1. This additional loss term improves the
realism in generated images and reduces artifacts.