Reasearch On Multi-dimensional Vibration Isolation Control System Based On A Parallel Mechanism

During the spacecraft’s mission life, the launch stage will experience the mostserve vibration and sorts of loading. Therefore, the loading environment during thelaunch stage is the key to the spacecraft’s life and security reliability. To improve theloading environment, the spacecraft reliability, and reduce the launch risks, This thesisis based on the application of whole-spacecraft vibration isolation, to research thevibration isolation platform is built by three degree-of freedom parallel mechanism, andto design the semi-active control strategy based on Magneto-rheological(MR) damper.First, the parallel mechanism3UPU/UPU with three translational degree-of-freedom accordance with the vibration direction is proposed as the vibration isolationplatform, and the DOF is computed and testified. Then the reason of the kinematic pairschoose were explained according to the whole-spacecraft isolation specific.Second, the stiffness and the press of different shape and different materials flexurehinges were studied, and the solution of the flexure hinges was gained. The rotationstiffness of the flexure hinges was computed.At last, the kinematics of the mechanisms was analyzed, the dynamics modelsconsidering the rotation stiffness of the flexure hinges was built used Kane method,which lays a foundation for the vibration simulation later. Then the vibration equation isderived from the dynamic equation, and two kind of controllers were designed appliedthe H infinities theory and optimal control theory respectively, the results of thesemi-active vibration isolation control system based on MR damper was studied by theMATLAB programming.The thesis adopts the parallel mechanism, applied the MR damper and the flexurehinges, to finish the isolation task by the controller, which give a way to thewhole-spacecraft isolation.