Soft Robot Skin With Conformal Adaptability for On-Body Tactile Perception of Collaborative Robots

Robot skin, as the physical interface between collaborative robots (cobots) and the external environments, could mediate on-body tactile signals for cobots to respond timely once a collision occurs during tasks and thus avoid damages to both cobots and surroundings. To achieve effective on-body tactile perception, robot skin should possess adequate conformal adaptability to be covered on various complex contours on the cobot, such as joints, while maintaining accurate and rapid sensing performance. In this letter, a soft robot skin consisting of an array of force-sensing units and a substrate with a serpentine structure was developed, both of which were made of porous material. The serpentine structure endows the developed skin with stretchable attributes. Thus, the skin could be conformally attached to complex surfaces of a cobot with less local stress, which was validated by finite element analysis. Taking the advantage of porous microstructure, the sensing units embedded in the substrate have exhibited high sensitivity and fast response time under external force, which are essential factors in real-time collision detection. Finally, experimental validation was carried out to verify the feasibility of deploying the developed soft robot skin on a robot arm to provide on-body tactile perception for a cobot.