The Dynamic Co-Simulation of Complex Mechanism and Control Systems for Multi-Axial Parallel Mechanism Manipulators

This study aims to investigate the analysis and control of the multi-axial parallel mechanism manipulators, including a three-axial pneumatic pyramidal parallel mechanism manipulator and a six-axial hydraulic Stewart-Gough platform. Through importing the 3D manipulator models drafted by SOLIDWORKS software, the dynamic simulation software ADAMS (Automated Dynamic Analysis of Mechanical Systems) can be implemented, and then the motion characteristics between components and joints setting can be built. Besides, the dynamic models of the pneumatic and hydraulic driving systems as well as the closed-loop control systems are derived and implemented via MATLAB/SIMULINK. Thus, through the co-simulation of ADAMS and MATLAB/SIMULINK, the dynamic models of the manipulators can be exported from ADAMS into the MATLAB/SIMULINK environment to process control simulation and analysis. Consequently, we can simplify the dynamic analysis of complex systems, improve the simulation result accuracy, and increase the design reliability.
Besides the dynamic analysis, the kinematic analysis of the manipulator systems is also necessary for the overall system analysis in this study. In the kinematic analysis, the geometric method is introduced to solve the kinematic relation between the actuated joints and the moving platform. A vector-loop closure equation is first established for each limb of the manipulator, and then the solutions for both the inverse and forward kinematics are obtained by solving the vector-loop equations.
In this study, the co-simulations of the dynamic models of manipulators via ADAMS and MATLAB/SIMULINK, including the inverse and forward kinematics, the pneumatic and hydraulic dynamic models, and the feedback controllers, are implemented for open-loop analysis and the closed-loop path tracking control respectively in the two manipulators. Besides, the path tracking control experiments of the three-axial pyramidal pneumatic parallel manipulator are also achieved and compared with simulation results for verification.