Development Of Thrust Direction Automatic Control System For Shield Machine

Structure and working principle of the shield machine are briefly introduced by this paper. Components and control mechanism of automatic thrust system and guidance system are analyzed. Automatic thrust system theoretical research state is reviewed and significance is proposed.Adjustable pressure control principle of single thrust cylinder is designed for Shenzhen power tunnel project shield machine. Proportional pressure relief valve is used to adjust thrust cylinder pressure in real-time. Large flow hydraulic reversing impact, safety factor and the rapid extension and withdraw are taken into consideration. Simulation test shows that the development of the new pressure adjustment system is accurate and sensitive and meets the needs of automatic thrust control.Based on coordinates of each cylinder and deviation curve of the guidance system, the calculation equation of the pressure control assignment is designed. In line with the characteristics of underground construction, the calculation formula of pressure adjustment is designed by the comparison of target value of the actual coordinates of the shield machine and deviation curve, and then corresponding PLC is written.AMESim software is used to simulate and analyze the shield machine hydraulic / mechanical thrust system. Taking the shield displacement as the control variable and deviation rectification curve as the target value, the relationship curve is obtained by shield machine automatic thrust system control model simulation. The simulation result shows that the shield machine can be advanced along the rectification curve with stable steering. The research and development of the automatic thrust system presents reference for the automatic operation of the shield machine.