Research On Active Vibration Isolation And Positioning Method Of Shipborne Precision Equipment Bearing Platform

With the development of the ship-borne servo-driven stable platform,the application of precision equipment on ships has become possible.However,the medium and high frequency mechanical noise of ships due to engine vibration and low frequency disturbances caused by waves hitting the hull are still the core factors affecting the stable operation of shipborne precision equipment.Therefore,the research on bearing platform technology with low-frequency positioning and medium-and high-frequency vibration isolation capabilities is the key to ensuring the stable operation of shipborne precision equipment.This thesis adopts the analysis ideas from the component level to the system level to clarify the structural design scheme of the bearing platform.The six-degreeof-freedom dynamic model of the active vibration isolation system of the bearing platform is further established,and according to the modal theory,the six-degree-offreedom modal decoupling method based on the position of the center of mass is clarified.A vibration isolation control strategy based on the modal decoupling method of load vibration feedback and base vibration feedforward is proposed.Through the analysis of the impact of the actual working surface of the shipborne stable platform,the positioning control bandwidth is clarified,and a positioning strategy based on the relative position control method of the three-degree-of-freedom center of mass in the horizontal direction and the relative position control method of each support point in the vertical direction is proposed;A simulation model of singledegree-of-freedom active control of the load-bearing platform was created based on mathematical simulation software.Furthermore,a hybrid controller parameter tuning method of "positioning first and then vibration isolation,limiting positioning bandwidth" is proposed,which solves the inherent contradiction between positioning and vibration isolation on the rigidity requirements of the system,and verifies the effectiveness of the hybrid control of positioning and vibration isolation.The realization scheme of the active vibration isolation and positioning hybrid controller is clarified,including the absolute speed feedforward controller which based on the physical model the relative position positioning controller,the absolute speed feedback controller.Based on the system stability,a parameter tuning scheme based on frequency domain for each loop is designed.In addition,the software and hardware of the active controller are designed and implemented.A load-bearing platform system was built in the experimental environment,and the positioning performance and vibration isolation performance of the system were verified respectively,and the effectiveness of the control scheme was verified through the hybrid control experiment of positioning and vibration isolation.The final experimental results show that the load-bearing platform can effectively ensure the positioning performance while having a significant vibration suppression effect.