Grip Force Control Using Vision-Based Tactile Sensor for Dexterous Handling

In this paper, we propose a force control method for robot grippers based on the degree of slippage using vision-based tactile sensor. Our tactile sensor consists of a CCD camera, LED lights, an acrylic plate and a spherical elastic body. The feature of this sensor is to measure “stick ratio”, which indicates the degree of slippage between a robot gripper and a grasped object. The stick ratio is used to control the grip strength. The proposed method doesn’t require any other information such as the weight of object and the friction coefficient. The gripper with the control can hold the grasped object while the robot gives a certain movement to the object. It is shown that the method makes it possible to achieve dexterous handling only using signals from the tactile sensor.