A Visual Positioning Method Based on Relative Orientation Detection for Mobile Robots

In this paper, a new visual positioning method based on corresponding points at two adjacent views is developed for mobile robots. A camera is mounted on a wheeled mobile robot with nonholonomic constraints. The camera whose intrinsic parameters are well calibrated can rotate around an axis perpendicular to the ground plane. The relative orientation and scaled position offsets of the mobile robot are computed from the corresponding points in the common part of the views despite their unknown positions in Cartesian space. The relative orientation is used in a simple visual dead reckoning method to modify the odometry information. Then, based on the relative orientation and modified odometry information, equations are given to determine the position and orientation of the mobile robot. Experiments are performed to verify the effectiveness of the proposed methods