This paper focused on the development of algorithms for a mobile robot dealing with the collision avoidance of multiple obstacles employing the degree of risk (DRM) and fuzzy function method (FFM), the DRM considered the information of the relative velocity and the distance between the obstacle and the mobile robot at the same tine, and the FFM was not only related with the relative velocity, the relative distance and the truning angle, but also with the maximum acceleration of the robot. It was analyzed and selected, in this paper, the obstacle collision avoidance maneuvers and built the behavior model of the system which are the sense, decision-making and continuous variable control, it was a complicated intermixing system. The simulation results verified the validity of collision avoidance maneuvers.