Optimal Configuration of a Downward-Facing Monocular Camera for Visual Odometry

Abstract

Background/Objectives: An accurate estimation of a robot’s pose is critical for autonomous mobile vehicles. Monocular vision-based odometry is one of the robust methods used for estimating the relative motion of vehicles by using only a stream of images acquired from a camera mounted on the vehicle. Methods: The location of the camera and its configuration can affect the quality of the localization process and the maximum permissible vehicle driving speed. In this work, the elements that can affect the permissible vehicle driving speed were recognized and the equations for this allowable speed were derived. Moreover, the optimal location and configuration of a downward-facing monocular camera that ensures the success of Visual Odometry for car-like ground vehicles in low-textured environment are presented after an extensive analysis. Findings: The results show that the suggested optimal camera configuration increases the permissible vehicle driving speed. Furthermore, the percentage of correlation mismatching between image frames is decreased as the suggested camera location avoids the negative consequences of shadows and directional sunlight that can add noise to image frames and interrupt the estimation of image pixel displacement. Application/Improvements: The suggested camera configuration could be implemented in various commercial mobile robotic applications, which utilize visual odometry for improved accuracy, efficiency and cost effectiveness.