Design, analysis, and testing of a novel compliant underactuated gripper

This paper proposes a novel compliant underactuated gripper with multiple working modes. Based on the pseudo-rigid-body method, a static analysis of different working modes is carried out, establishing an analytical relationship between the output grasping forces and the input load. For the enveloped grasping mode, an algorithm to determine the static equilibrium position is given. Furthermore, a parametric optimization algorithm based on gradient descent is designed to obtain the maximum grasping forces. The effectiveness of the multiple grasping modes, the grasping force models, and the optimization algorithm are verified by a dynamic simulation package and finite element analysis as well as by experimental tests. Finally, various grasping experiments are conducted to further validate each working mode, the stability of grasping, and the ability to protect fragile objects.This paper proposes a novel compliant underactuated gripper with multiple working modes. Based on the pseudo-rigid-body method, a static analysis of different working modes is carried out, establishing an analytical relationship between the output grasping forces and the input load. For the enveloped grasping mode, an algorithm to determine the static equilibrium position is given. Furthermore, a parametric optimization algorithm based on gradient descent is designed to obtain the maximum grasping forces. The effectiveness of the multiple grasping modes, the grasping force models, and the optimization algorithm are verified by a dynamic simulation package and finite element analysis as well as by experimental tests. Finally, various grasping experiments are conducted to further validate each working mode, the stability of grasping, and the ability to protect fragile objects.