Obstacle detection by disparity prediction stereopsis method

摘要

Abstract The authors devised a method (disparity prediction Stereopsis method) which calculates the range of the disparity which corresponds to the space where a robot is due to move and predicts the existence or non‐existence of the object by matching the edge segment extracted from the stereo images with the range of the disparity. The method is applied to the obstacle detection in the navigation of the mobile robot. The object to be detected is a still object standing on a floor. First, the existence of the object is predicted by the stereo matching of vertical edges. The remaining edges are examined only if the matched vertical edge exists. As a result, the efficiency is improved. In this method, the range of search is restricted and local matching is tried. Consequently, an incorrect match (false match) is produced easily in the background, in the environment with low contrast. To remedy this adverse effect, the floor region extraction process is executed by assuming the spatial continuity and the similarity of the gray‐level distribution in the near region. If the lower end of the matched edge is contained in the floor region, the object is decided as a candidate for the obstacle. By this decision scheme, the probability of misdetection of the object which does not interfere with the space where the robot is due to move such as the object far and high above the viewpoint and the object hanging on the front wall can be reduced. This improves the reliability. By the indoor evaluation experiment, such as the scene of laboratory, the usefulness of the method is verified. The motion control of the robot is attempted in an environment simulating a nuclear power plant.