Research On Attitude Control Strategy Of Φ6m Earth Pressure Balance Shield Tunneling Machine

As the main equipment of tunnel excavation,shield machine undertakes the tasks of excavation,support and slag discharge in the process of tunnel construction.With the increasing demand of shield tunneling,the geological complexity of tunnel excavation becomes obvious,which poses a challenge to the geological adaptability of shield tunneling machine.The attitude control technology of shield machine is the key technology to guarantee the tunneling of shield machine along the designed axis,and its control performance directly affects the safety,construction efficiency and tunnel forming quality.The attitude control strategy of shield machine should not only reduce the actual and designed axes of tunnel,but also consider the problem of soil pressure balance Therefore,on the basis of extensive reading of related papers and literatures of shield machine propulsion system control at home and abroad,the pressure and velocity compound control strategy of single zone propulsion system of shield machine was studied.On this basis,the attitude control strategy of shield tunneling machine is designed according to the requirements of trajectory tracking and attitude control in actual tunneling.Thus,the earth chamber pressure is maintained and the axis of shield machine design is tracked.The main contents of the paper are as follows:(1)Based on the driving principle and structural characteristics of the shield propulsion system,the mechanical-electro-hydraulic co-simulation platform of the shield propulsion system is built,and the open-loop motion characteristics of the shield propulsion system are simulated and analyzed.The simulation results show that the response time is long in the open-loop regulation of the propulsion system,and the pressure and speed matching regulation requirements are met.The propulsion system is prone to stall,which leads to the attitude deviation of shield machine.(2)In view of shield thrust system pressure,the speed matching demand,based on the step integral adaptive control algorithm,the design of shield machine hydraulic system pressure speed single partition compound control strategy,and through the designed observer and adaptive rate observation of unknown parameters in the controller as well as the compensation of load estimation and model uncertainty.Through simulation,the performance of control strategy under speed regulation,mutation load and disturbance load is analyzed.The simulation results show that the controller can meet the pressure and speed matching requirements of the propulsion system of single zone shield machine.Compared with PID controller,the response time of the proposed controller is shortened by more than 15% and the overshoot is reduced by more than 20% in the process of propulsion system regulation.When the load is disturbed,the amplitude of system pressure fluctuation is reduced by more than 50%.(3)According to the experimental verification requirements of the pressure and speed composite controller,the comprehensive performance test bench of the hydraulic cylinder was reformed,and the control performance of the controller under the conditions of speed regulation,mutation load and disturbance load was studied experimentally,which further verified the effectiveness and stability of the controller.(4)In view of the attitude control requirements of the shield machine,numerical characterization was carried out based on the kinematics equation of the propulsion system of the shield machine and the design axis of the shield machine.The expected pose and actual pose of the shield machine were solved,and then the flow distribution characteristics of the single zone propulsion system and the expected motion characteristics of the propulsion hydraulic cylinder were obtained.Through the design of pose controller,the composite control of shield machine attitude,system pressure and speed is realized.Based on the mechanical-electro-hydraulic co-simulation platform,the tracking effect of the design axis of shield tunneling machine under the control of pose controller and the performance of controller under the conditions of speed regulation,non-uniform load and uniform load were simulated.The simulation results show that the attitude Angle deviation is less than 0.000003 radians in the axis tracking of tunnel design of the shield attitude controller designed in this paper.In the process of load change,the speed overshoot is less than 0.07mm/s,and the pressure error is less than 0.5Mpa Under 100000 N random load fluctuation,the speed error is less than 0.02mm/s,the pressure error is less than 0.06 Mpa,and the position error is less than 0.02 mm.The attitude controller has good attitude control performance.