Type Synthesis of 5-DOF Redundantly Actuated Parallel Mechanisms for Super-Large Components

Super-large components with complicated surfaces are used for many applications, the processing method of super-large components with complicated surfaces is also problem to be solved. The 5-edgrees of freedom (DOF) redundantly actuated parallel mechanisms (RAPMs) can be used as a movable parallel module in a multi-axis machine center to process super-large components with complicated surfaces. This paper focuses on type synthesis of 5-DOF RAPMs redundantly actuated parallel mechanisms for Super-large components. First, two articulated moving platform and four kinds of limbs are designed based on configuration evolution and Li group theory. By means of the proposed articulated moving platforms and four kinds of limbs, a series of 3T2Rand 2T3R are synthesized. Then, kinematics of the proposed RAPM is analyzed. To ensure the proposed RAPM without impact, a new trajectory planning method combining quadratic function with cosine is proposed and applied to motion simulation. The results show the RAPM not only possesses large output rotational angles, but also verifies the efficiency of the trajectory planning method in motion simulation. The work lays the foundation for solving the processing method of super-large components with complicated surfaces.