Research On Electro-Hydraulic Control System Of Ocean Depth Simulator

Ocean depth simulator is an essential part of the hardware-in-the-loop simulationsystem of underwater vehicle. Cooperated with relevant equipment, ocean depthsimulator can simulate different water pressure, providing real underwater conditions ofvaried water pressure for experimental subjects. Developing ocean depth simulator withhigh reliability and precision can shorten the development cycle of underwater vehicleand reduce its cost.Firstly, according to relevant technologies of hydraulic transmission, the overall planwhich includes hydraulic system and control system of ocean depth simulator isdetermined in this paper. Based on the calculation results of key parameters, importantcomponents of ocean depth simulator are selected and the mechanical construction of thesystem is designed.Secondly, based on hydraulic servo control theories, the control construction ofocean depth simulator is analyzed and the mathematical description is established in thepaper. The system features are studied which include frequency characteristic andstability.Thirdly, various kinds of control algorithms are researched in the paper. Because ofthe features on fast response and high precision, a classic control method PID is notsuitable for ocean depth simulator. However, the ZPETC (zero phase error trackingcontroller) can reduce the large phase error in high-frequency response of depth simulator,thereby improving dynamic tracking accuracy of the system. Consequently, a PIDcontroller based on GA (genetic algorithm) and a ZPETC controller are designed, whichcombine the advantages of these two control methods. Based on MATLAB, thesimulation on the system is implemented and the results show that the complex control algorithms presented in the paper improve the control performance of the systemeffectively.Finally, functional requirements of ocean depth simulator software are analyzed andthe structure, organization and functional modules are set up. Based on LabView, RTX,Microsoft Visual C++, software with strong real-time property is designed as a platformfor the future experiments.The researches lay an excellent foundation for further study on improving theprecision of pressure control based on depth simulator.