Research On Design And Control Of Motion Platform Based On Stewart

Since came up, Stewart platform, a classic kind of6-DOF manipulator, with yearsof research and development, has been widely applied in various fields. And6-DOFmotion platform is an extended branch in entertainment industry, which is a emergingand booming industry in China. Because of its high-fidelity and good experience,6-DOF motion platform has broad market application prospect.Based on the technical indicators, the structure of6-DOF motion platform isdesigned, as well as the hardware, software and control strategy of the control system.And by debugging experiment, the feasibility of the designed system is proved.Firstly, establishing the kinematics and dynamics models for simulation to designthe parameters of the critical components, such as upper and lower hinges, hydrauliccylinders, servo valves and hooks. Then based on the established hydraulic controlmodel, the characteristics of the electro-hydraulic control system is analyzed. Anddynamic pressure feedback and feedforward control are used to improve the systemdamping, and correct phase lag and amplitude attenuation. At the same time, therationality of the platform structure and the electro-hydraulic control system can beproved via joint simulation of MATLAB andADAMS.According to the requirements of dynamics characteristics of the motion platform,a Fuzzy-PID controller is designed. Comparing the simulation results proves that theperformance of Fuzzy-PID controller is superior to conventional PID controller withdifferent input signals. In addition, through the joint simulation, it proves that the fuzzyPID controller also perform well when controlling the overall platform.Considering of the characteristics of6-DOF platform, such as multi-channel, highreal-time performance, large real-time calculation and traffic, a microcontroller unit(MCU), based on C8051F120microcontroller, is developed to act as lower computer,and PC acting as host computer. Also, their control program is programed. Debuggingon an existing6-DOF flying simulator, the whole control system is proved to be feasiblewith good real-time performance and reliability.Adiscrete three dimensional inverse M series generator is used for identification asinput signal. Based on the identified model, a feedforward controller is designed toimprove the dynamic behavior of the system. In the end, Fuzzy-PID controller is alsoapplied to do experiment, and proved to be with good performance.