A novel acceleration capacity index based on motion/force transmissibility for high-speed parallel robots

Dynamic performance evaluation is an open question considering three main challenging issues: (a) how to avoid performance indices physically inconsistent considering different dimensions of translational and rotational performance of parallel robots; (b) how to accurately evaluate the performance of the whole robots considering different capacity of driving motors, active arms and moving platforms; (c) how to understand the inner relationship between the dynamic performance and parameters of robots. In this paper, through matching the driving system with the parallel mechanism, an acceleration capacity index of the whole robot is proposed for high-speed parallel robots with mixed types of DOFs (translations and rotations). From the view of power transmissibility, the comprehensive interaction mechanism of motion/force transmissibility to the acceleration capacity of the robot is analyzed and presented in the proposed index. Thus, the index can measure the acceleration capacity accurately. For validation purpose, this index is applied to acceleration capacity evaluation of a high-speed parallel robot, identifying a suitable workspace to reduce the driving torque. This index is general and can be further applied to parameters optimization for different types of high-speed parallel robots.