Obstacle avoidance using virtual impedance wall for limb mechanism robot

An obstacle avoidance method using virtual impedance wall is proposed for multi-legged robot. The swing leg employs compliance control to avoid the collided object and the robot keeps the moving direction as much as possible while swing legs keep a preferred operating region. The preferred operating region is surrounded with virtual impedance wall. When the leg comes to go over the threshold of preferred operating region, the moving direction is modified by the virtual repulsive force from the virtual impedance wall to avoid the workspace limitation. Moreover, the pattern recognition technique with the support vector machine is implemented for estimating the contact point between the object and the body by using the data set of the error of each leg. The virtual impedance field is set at the estimated contact position to direct the aspect of avoidance.