Design and Test of an Active Pneumatic Soft Wrist for Soft Grippers
Guangming Chen,
Tao Lin,
Shi Ding,
Shuang Chen,
Aihong Ji,
Gabriel Lodewijks
Affiliations
Guangming Chen
Laboratory of Locomotion Bioinspiration and Intelligent Robots, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016, China
Tao Lin
Laboratory of Locomotion Bioinspiration and Intelligent Robots, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016, China
Shi Ding
College of Civil Aviation, Nanjing University of Aeronautics and Astronautics, No. 29 Jiangjun Avenue, Nanjing 210016, China
Shuang Chen
School of Mechanical Engineering, Xi’an Jiaotong University, No. 28 Xianning West Road, Xi’an 710049, China
Aihong Ji
Laboratory of Locomotion Bioinspiration and Intelligent Robots, College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016, China
Gabriel Lodewijks
School of Engineering, College of Engineering, Science & Environment, Callaghan Campus, University of Newcastle, University Drive, Callaghan, NSW 2308, Australia
An active wrist can deliver both bending and twisting motions that are essential for soft grippers to perform dexterous manipulations capable of producing a wide range movements. Currently, the versions of gripper wrists are relatively heavy due to the bending and twisting motions performed by the motors. Pneumatic soft actuators can generate multiple motions with lightweight drives. This research evaluates a pneumatic soft wrist based on four parallel soft helical actuators. The kinematics models for predicting bending and twisting motions of this soft wrist are developed. Finite element method simulations are conducted to verify the functions of bending and twisting of this wrist. In addition, the active motions of the soft pneumatic wrist are experimentally demonstrated. Based on sensitivity studies of geometric parameters, a set of parameter values are identified for obtaining maximum bending and twisting angles for a bionic human wrist. Through simulation and experimental tests of the soft wrist for a soft gripper, the desired bending and twisting motions as those of a real human hand wrist are established.
