Research And Implementation Of The Control System For Hydraulic Manipulator Working In A Simulated Environment Of Deep Sea

With the development of human society, land resources become less and less. In this case, the development and utilization of marine resources has been urgent needs. Equipment of development of marine resources is indispensable tools for exploration and exploitation of marine resources. Development of manipulator system working in deep-sea simulation environment can provide good operation means and simulation condition in simulate deep-sea environment, and also can promote national’s development capability in deep-sea manipulator system technology.In the paper, overall scheme of the deep-sea manipulator system was analyzed. High pressure chamber which is used to simulate deep-sea environment, the manipulator body structure and the manipulator operational requirements were researched. On this basis, functional requirements of the manipulator control system were analyzed, and the principles and framework of control system was developed.According to the manipulator system environment, functional requirements and drive way, a series of technical parameters were got for preparing to set up the control system. This paper discusses communication between terminals in the system and the design process in detail. A variety of communication methods of PLC are compared and analyzed, and communication ways and hardware are selected. Communication between IPC systems and console PLC system is established with UDP, and command can be sent from IPC to actuator and data can be uploaded from sensors to IPC. Analog acquisition module got displacement signal from 4 sensors which are installed in the hydraulic cylinders, and transmitted to the PLC. In the PLC, the data is processed and converted. Modbus serial communication format is analyzed, and temperature and pressure of hydraulic station are monitored with Modbus communication and transmitter data to PLC. Finally, IPC serial communication function is used to complete communication connection between industrial control handle and IPC to achieve control manipulator directly with the industrial handle.The control system communication program and interactive interface are developed based on MFC with C++ in the VC ++ development environment. In software development process, the OpenGL graphics interface is used to convert three-dimensional model into program code and display the 3-D model in control interface, and achieve the real-time driving for three-dimensional model with the data which is collected into PLC and upload to IPC.A straight-line trajectory planning is analyzed based on the mechanical hand kinematics. Experiments are made for 400 mm vertical straight path with three methods: the class-PWM method, automatic tracking method and waypoints control method. The results showed that manipulator cannot run stable in the first two methods and under control waypoints control method, the manipulator can achieve consistent runs, but there are still a few points short stagnation. In addition, the manipulator system was stepwise debugging and functional testing. Weight-bearing capacity of the manipulator, the gripper grip force and torque test, the hydraulic system pressure test, and underwater test for the overall system have been done. Intermediate and final commissioning of underwater test results show that the design of the system can be stabilized effectively and meet the functional requirements of underwater manipulator.