A Rigid-flexible Coupling Three-finger Soft Gripper for Fruit Picking

In this paper, a rigid-flexible coupling three-finger soft gripper is present to grasp fruits. It can solve the problem that the traditional rigid manipulator is easy to damage the target object and the flexible manipulator has insufficient grasping force. A motor is used to drive the soft finger uniformly to reduce the complexity of the control system. The soft gripper system adopts PID control algorithm to realize closed-loop control. A linkage mechanism is designed to convert the curvilinear motion driven by the motor into linear motion. To verify the gripping performance of the soft gripper, finite element simulations and experiments are carried out. The results show that the soft gripper has good adaptability, stability, and versatility. And its gripping range is sufficient to cover the size of most fruits. Moreover, the soft gripper could successfully grasp fruit without damaging fruit skin.