Inertial Navigation Sensor Integrated Motion Analysis for Obstacle Detection

Land navigation requires a vehicle to steer clear of trees, rocks, and man-made obstacles in the vehicle's path while vehicles in flight, such as helicopters, must avoid antennas, towers, poles, fences, tree branches, and wires strung across the flight path. Automatic detection of these obstacles and the necessary guidance and control actions triggered by such detection would facilitate autonomous vehicle navigation. An approach employing a passive sensor for mobility and navigation is generally preferred in practical applications of these robotic vehicles. Motion analysis of imagery obtained during vehicle travel can be used to generate range measurements, but these techniques are not robust and reliable enough to handle arbitrary image motion caused by vehicle movement. However, many types of existing vehicles contain inertial navigation systems (INS) which can be utilized to improve interest point selection, matching of the interest points, and the subsequent motion detection, tracking, and obstacle detection. We discuss an inertial sensor integrated optical flow technique for motion analysis to achieve increased effectiveness in obstacle detection during vehicle motion.