Abstract: A novel and effective obstacle avoiding method for mobile robot is developed.First, a maximal encasing box and relative velocity between obstacles and the robot are used to analyze the orientation of collision.The principles of le ast changes and optimal changes of velocity are used to realize the robot's obstacle avoidance capability.Simulation results show that this method can help the robot safely reach a target in a dynamic environment where both stationary and moving obstacles exist.

Key words: dynamic obstacle, maximal encasing box, mobile robot