Research Of Multi-Cylindeff Orce Control Strategies Based On High Speed On/off Valves

The coordinated force control of hydraulic systems is becoming more and more widely used and complex, so how to ensure the reliability and security is one of the important aspects to develop hydraulic technology. Therefore, this thesis builds a test rig of multi-cylinders based on high speed on/off valves to research the force control. CMAC+PID compound control strategy is used, and presents a new strategy named'intelligent PID control based on CMAC'. Through Matlab RTW xPC, the research and analysis is done to the test rig. The simulation and experiments show that the intelligent PID control strategy based on CMAC can enhance the accuracy, robust and anti-jamming capability of the multi-cylinder system's force control.Around the topic, this thesis expands in many aspects:building of the test rig, hardware selection, modeling, analysis on simulation and experimental results based on PID and intelligent CMAC control strategy, writing of control interface, etc.The main work is as follows:1) Based on the research aim, the thesis selects optimal cylinders, high speed on/off valves, force transducers, and other components to build the test rig. The Matlab RTW xPC of Math Works is used as the control platform, and the PCI 1711 multifunction DAQ card is used as the communication platform between software and hardware, to acquire and output signals2) The thesis completes the modeling of the test rig, and uses PID control algorithm to do initial simulation and experiments. Through analysis, the disadvantage and improvement needed of PID is confirmed.3) The thesis adopts the CMAC+PID compound algorithm to control the test rig with the combination of AMES im and Matlab. Through the comparison of simulation and experiments results, CMAC+PID control strategy can enhance the control ability, but still has disadvantage.4) The thesis presents a new algorithm-intelligent PID control based on CMAC, through the improvement of CMAC+PID, and the simulation and experiments are carried out with this strategy. The comparison of results shows that the intelligent PID control based on CMAC has great advantage in improving the accuracy, robust and anti-jamming capability. With this strategy, the full ability of the test rig can be exerted, and the force of multi-cylinders can be controlled ideally.5) The thesis combines LabVIEW and Matlab through calling dll, to write the control interface, and this leads to easy, practical and friendly operation of the research of multi-cylinder system's force control.