Abstract
Our research group has developed a tracked mobile robot "kenaf' for high-speed exploration of the confined space such as the underground cities. The kenaf can move about 3 km/h and can get over about 40 cm step. However, it is difficult to pass through the steps and the narrow spaces quickly by remote control. The authors propose an autonomous speed adjustment system based on measurement of environmental shapes. The system limits the maximum speed of the robot when the obstacles are detected within the kinematics-based ellipsoidal areas. The system also limits the speed when the environmental shape ahead is the steps or the slope. The distances of the obstacles were measured by using the laser range sensor. The environmental shape ahead was obtained by using the range image sensor. The validity of the system was experimentally evaluated in a narrow space and a step.
