Design Of The Control System For The 6-DOF Swing Platform

Six free-degree swing platform is used for simulation experiments of weapon aim-line stabilization systems on cars, ships or airplane. It's also an important simulative training system for drivers, sailors and pilots. Six free-degree Swing platform adopts parallel Stewart platform mechanism. The Stewart platform can let its payload-platform move with 6-DOF in the workspace through the extension and contraction of the six legs. The major research works completed in this dissertation includes: six free-degree swing platform system design, kinematics theory, pose error analysis and control methods.First, configuration is analyzed based on performance guide line and characteristics of six Free-degree swing platform. Then hardware and software frameworks are designed.Second, the dynamic and kinematic characteristics of the Stewart platform are analyzed. Kinematic inverse solution equations are build for different motion states. These equations are the foundation of servo control system design for Stewart platform. Also, a numerical method is derived for determining the forward solution of position of a parallel mechanism with 6 degree of freedom. Then, the relations of output pose errors, configuration parameters and pose parameters are analyzed. Pose error compensation model is built. A method is designed for Pose error compensation in theory. This method could be used for compensating the inverse solution of the extension and contraction of the six legs.At last, six free-degree swing platform has strong coupling, heavy upload and nonlinearity characteristics, so a PID-fuzzy compound control method is adopted. A variety of simulations are carried out to support the analytic results with Matlab/Simulink. The analysis shows that the compound control method with integral tache is able to eliminate steady state error in pure fuzzy control system, improve accuracy. Also, it's good for anti interference caused by coupling and robustness.