A capacitance-based proximity sensor for whole arm obstacle avoidance

The authors address the issue of collision avoidance in unknown or partially modeled environments using a capacitative sensor. An eight channel capacitance-based sensor system which can detect obstacles up to 400 mm away has been developed. This sensor can detect both conductive and nonconductive obstacles of arbitrary color and shape. The sensor hardware was reliable and inexpensive, and may be fabricated using flexible printed circuit boards to provide whole-arm and joint protection for any robot or manipulator. Simple collision avoidance control algorithms have been implemented on a two-link robot arm. The sensor and control system enable the robot arm to avoid a conductive post and a concrete block