Topology optimization and prototype of a three-dimensional printed compliant finger for grasping vulnerable objects with size and shape variations

This study presents a topology optimization method to synthesize an innovative compliant finger for grasping objects with size and shape variations. The design domain of the compliant finger is a trapezoidal area with one input and two output ports. The topology optimized finger design is prototyped by three-dimensional (3D) printing using flexible filament, and be used in the developed gripper module, which consists of one actuator and two identical compliant fingers. Both fingers are actuated by one displacement input, and can grip objects through elastic deformation. The gripper module is mounted on an industrial robot to pick and place a variety of objects to demonstrate the effectiveness of the proposed design. The results show that the developed compliant finger can be used to handle vulnerable objects without causing damage to the surface of grasped items. The proposed compliant finger is a monolithic and low-cost design, which can be used to resolve the challenge issue for robotic automation of irregular and vulnerable objects.