The optimal slurry spraying process of the slurry spraying robot requires the gun of the slurry spraying robot to be controlled with respect to the position and attitude of the roadway.The joint angle was obtained by solving for the position of the gun in horizontal or vertical motion relative to the base,and the joint angle was measured in real time using an inclination sensor,a closed-loop position was formed based on the solved angle and the measured angle to drive the joint to complete the spraying action.The simulation model of the joint position closed-loop control system based on the inclination sensor and load-sensitive proportional valve control hydraulic system was established by using MATLAB/Simulink,and the delay caused by the dead zone of the proportional valve was eliminated by using the voltage step compensation method,and the influence of the pure hysteresis link on the control system was eliminated by using the improved Smith predictor,the rationality and feasibility of the method was verified finally.