Study on the vision-based indoor navigation of an Alife robot

It is a prerequisite for a mobile robot to realize steady and reliable navigation. But its reliability is often weakened by an unavoidable slip and some incorrigible drift errors of sensors, especially after a long distance navigation. Although perceptual landmarks were solutions to such problems, it is easy to miss landmarks at some specific spots when the robot moves at different speeds, especially at higher speeds. And if the landmarks were put in any intervals, or if the illumination conditions were not good, it is more difficult to find them. In order to detect and extract the artificial landmarks robustly under different illuminating conditions, some low level but robust image processing technique was implemented. The moving speed was controlled with the visual servoing control method. When the robot suddenly can not find some specific landmarks at some specific spots because of the higher speed or rapid turn of the road, it will search for the landmarks based on its intelligence, the inertia of the previous motion, and find the landmark in the shortest time. These methods were verified by the reliable vision-based indoor navigation of an Alife mobile robot.