Study On Hydraulic Control System Of Six Degrees Of Freedom Cargo Receiving Platform At Sea

Under the disturbance of the waves,the ship will produce constant motion,which will affect the loading and unloading of the cargo on the ship.The six degrees of freedom platform can offset the movement of the ship to ensure the smooth operation of loading and unloading.The energy-saving hydraulic control system of cargo receiving platform with three-chamber hydraulic cylinder can reduce the energy consumption of the system and realize symmetrical control at the same time.Firstly,the structure parameters are determined according to the working conditions of a cargo receiving platform,and the expected displacement of each hydraulic cylinder is calculated by the kinematic inverse solution of the parallel mechanism,and the displacement curves of six hydraulic cylinders are obtained,and the working space of the upper platform is solved.The virtual prototype model was established by ADAMS,the cargo receiving platform was simulated,and the dynamic parameters such as displacement,speed and force of each hydraulic cylinder were analyzed,which provided load parameters for subsequent hydraulic system design.In view of the present widely used to single out the receiving platform rod oil cylinder hydraulic system installed power is big,the energy utilization rate is low,the disadvantage of asymmetric control,we design a three cavity hydraulic cylinder,accumulator inferior vena connections,to balance the gravity load,recovery of gravitational potential energy,the other two connected to the servo valve cavity and equal work area,compared with single pole system,can reduce consumption of energy of the system,and can realize symmetrical control,but its dynamic characteristics will be affected.The coupling of six hydraulic cylinders with three cavities in the cargo receiving platform will lead to the dynamic characteristics of the platform become worse.Amesim-adams joint simulation is used to study the influence of the coupling of the hydraulic cylinders on the dynamic characteristics of the cargo receiving platform.In order to solve the problem that the dynamic characteristics of the receiving platform become worse,BP neural network PID control was selected as the control strategy of the system,and the dynamic characteristics of the system were determined by simulink-amesim-adams joint simulation.