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This paper presents the advantages of a single-camera stereo omnidirectional system (SOS) in estimating egomotion in real-world environments. The challenge of applying omnidirectional stereo vision via a single camera is what separates our work from others. In practice, dynamic environments, deficient illumination, and poor textured surfaces result in the lack of features to track in the observable scene. As a consequence, this negatively affects the pose estimation of visual odometry systems, regardless of their field of view. We compare the tracking accuracy and stability of the single-camera SOS versus an RGB-D device under various real circumstances. Our quantitative evaluation is performed with respect to 3D ground-truth data obtained from a motion capture system. The datasets and experimental results we provide are unique due to the nature of our catadioptric omnistereo rig, and the situations in which we captured these motion sequences. We have implemented a tracking system with simple rules applicable to both synthetic and real scenes. Our implementation does not make any motion model assumptions, and it maintains a fixed configuration among the compared sensors. Our experimental outcomes confer the robustness in 3D metric visual odometry estimation that the single-camera SOS can achieve under normal and special conditions in which other perspective narrow view systems such as RGB-D cameras would fail. [ABSTRACT FROM AUTHOR]

This paper presents a new holistic vision-based mobile assistive navigation system to help blind and visually impaired people with indoor independent travel. The system detects dynamic obstacles and adjusts path planning in real-time to improve navigation safety. First, we develop an indoor map editor to parse geometric information from architectural models and generate a semantic map consisting of a global 2D traversable grid map layer and context-aware layers. By leveraging the visual positioning service (VPS) within the Google Tango device, we design a map alignment algorithm to bridge the visual area description file (ADF) and semantic map to achieve semantic localization. Using the on-board RGB-D camera, we develop an efficient obstacle detection and avoidance approach based on a time-stamped map Kalman filter (TSM-KF) algorithm. A multi-modal human-machine interface (HMI) is designed with speech-audio interaction and robust haptic interaction through an electronic SmartCane. Finally, field experiments by blindfolded and blind subjects demonstrate that the proposed system provides an effective tool to help blind individuals with indoor navigation and wayfinding. [ABSTRACT FROM AUTHOR]