Obstacle avoidance control of humanoid robot arm through tactile interaction

In this paper we introduce a novel concept of obstacle avoidance through tactile interaction. The implementation of the approach was realized on humanoid robot arm with optical torque sensors distributed to each robot joint. When manipulator collides with an object, the control system enables to follow the object outline smoothly till robot reaches the target point. Such approach ensures not only safe obstacle avoidance but also acquisition of indispensable information about environment. The methods of object stiffness calculation, contact point estimation, and shape interpolation are detailed in the paper. The possible tasks of the robot with intelligent whole-arm obstacle avoidance control are summarized and illustrated in this work as well. The controllable compliance of robot arm joint can be extremely useful in a wide range of applications.