Topology Design and Dynamic Modeling of a 2T Parallel Mechanism with the Larger Workspace and Symbolic Forward Kinematics

According to the design method for parallel mechanisms (PM) based on the position and orientation characteristic (POC) equation, a two-translation (2T) PM with zero coupling degree is designed and its topology structure is analyzed. Then, by the kinematic modeling principle based on topological characteristics, the symbolic forward kinematics is given, and the inverse solution of the position, the Jacobian matrix of the moving platform, the velocity and acceleration of each component are derived. Next, the workspace of the mechanism is calculated based on the forward-solution formula. Finally, the ordered-single-open chain method based on the principle of virtual work is used to analyze the dynamics of the PM, and the actuated torque and the counterforce of some pairs are obtained. The results show that the PM has a large continuous singularity free workspace and better kinematic and dynamic performance.