Design, mathematical modeling and dynamic dimension synthesis for a modular parallel robot with end-articulated structure

In this paper, topology design, mathematical modeling and dynamic dimension synthesis methodology for a modular parallel robot (named 'Y3') with end-articulated structure and only revolute joints are systematically investigated. Firstly, to obtain the target configuration, the traditional explicit moving platform is topologically evolved into the end-articulated structure, and the degrees of freedom and kinematics of the robot are anatomized correspondingly. Secondly, based on Kane's formulation, a systematical modeling methodology is proposed, and the robot's refined/simplified dynamic models are established, respectively. To validate the validity of the dynamic models, a versatile and accurate multi-body dynamics simulation test model is developed employing Matlab/Simscape platform. On this basis, three types of dynamic performance evaluation indices that cover inertia force, Centrifugal/Coriolis force, and gravity terms are proposed, and the geometric constraints and kinematic performance constraints of robot are comprehensively examined, achieving the establishment of a multi-objective dynamic dimension synthesis model which considers adequately the kinematic and dynamic performance of system. Finally, the optimal dimension parameters of robot are obtained by employing synthetically monotonicity analysis and genetic algorithm, and the comprehensive performance is illustrated both before and after optimization. The results suggest that the Y3 robot features a simple structure and enhanced overall performance by the proposed design methodology, which has potential application prospects in the occasions of high speed and high dynamic response.