Key Technology Of Ship Auxiliary Machinery Motion Platform Based On Parallel Mechanism

Under laboratorial environment, motion platform of ship auxiliary machinery is experimental equipment that simulates movement of the warship on the water surface, can accomplish marine equipment performance test. The 3-DOF paralleled motion platform in the topic can simulate the warship movement of rolling, pitching and heave in special oceanic condition; it is important use value to the development of marine equipment performance test and ship motion control environment.Motion platform studied in the topic is a product that integrated mechanical, electronic and hydraulic technology. It refers to many knowledge fields, such as mechanism, kinematics, dynamics and control system etc. The paper mainly accomplished the design of mechanical body and hydraulic servo system, the analysis of kinematics and dynamics.First, according to the performance index of the system, the author selected an applicable motion platform, analyzed freedom of mechanism with screw theory. On that basis, the structure of the mechanical body was designed, forward and backward solution about its movement postures of space were computed and analyzed.Secondly, the paper carried on simulation with multi-body dynamics software ADAMS, got the kinematics and dynamics characteristics curve, thus gave the methods of solving kinematics and dynamics of motion platform of parallel mechanisms based on ADAMS, and verified the accuracy of design scheme and solid model.Finally, the methods of electro-hydraulic proportional control were used in the closed-loop control system and the simplified schematic of hydraulic system was accomplished; According to the motion index of the platform, the main hydraulic components were selected, the mathematical model of non symmetric valve controlling non symmetric cylinder were established, the transfer function of the system was gained. The author did some simulation analysis about the control system with disturbance and without disturbance. Because the system can not satisfy the demand of the control accuracy, the author used PID emendation, gained more satisfactory electro-hydraulic position servo control system.