Design and Kinematic Modeling of Wrist-Inspired Joints for Restricted Operating Spaces

In this paper, a wrist-inspired joint with an integrated drive system is designed to realize pitch and yaw simultaneously. First, a wrist-inspired joint with a modular design using an integrated drive system is designed, which for the first time offers the flexibility of soft joints and the high rigidity of discrete joints. On the basis of this, the multilevel mapping between servos, wrist-inspired joints, and end-effectors is first analyzed. Furthermore, wrist-inspired joints are applied in manipulators and grippers. Additionally, the kinematic model of wrist-inspired joint manipulators is established based on the vector product method, and the damped least squares method is used to solve the inverse kinematics. Finally, some groups of experiments are conducted on a self-built experiment platform. Experimental results of two applications, including a manipulator and a gripper, verify the flexibility and maneuverability of designed wrist-inspired joints.