Abstract: According to the contradiction between the large stroke and high precision of the parallel mechanism, a novel macro-micro 3-RPR parallel mechanism was presented which used the electrohydraulic servo control system as the macro driven and used the piezoelectric precision control system as the micro driven. Then, the macro-micro coupling dynamic model of the macro-micro 3-RPR parallel mechanism was deduced by principle of Virtual work. Its multi-software co-simulation model was built, including Adams mechanical module, AMESim hydraulic and piezoelectric diver module, Matlab/Simulink control module. According to the 3-RPR parallel mechanism characteristics of multi-input multi-output, nonlinear, strong coupling and so on, its control simulation research was conducted by using the fuzzy PID method. The simulation results show that compared with traditional PID, the single rod static and dynamic performance is improved by using the fuzzy control method and the macro-micro 3-RPR parallel mechanism can achieve high precision positioning of large stroke.

Key words: macro-micro driven, 3-RPR, parallel mechanism, fuzzy PID, control simulation