A 2-DOF active complaint gripper for robotic applications

This paper describes the construction, control and test results of a planar active compliant gripper. The compliance is provided by manipulating the part, held by the gripper fingers, in response to external forces exerted on the part during the process. The gripper consists of two parallel fingers, driven separately by DC motors, mounted on a translation stage perpendicular to their axis of motion. This configuration enables grasping an object and manipulating it in X-Y plane. The gripper is instrumented with force sensors capable of sensing the grasping force and the external forces exerted on the object. These force readings, in conjunction with a predetermined policy (dictated by the task to be performed) are used by a controller to manipulate the part. The gripper can be used for tasks such as insertion, edge following, task geometry tuning, etc. As an example, single peg/hole insertion experiments were conducted, and the results were compared with those obtained with a passive RCC.