Design and test of automatic leveling system for transplanter in hilly and mountainous areas

Aiming at the problem that the transplanting effect of the transplanting machine body is poor due to the incline of the transplanting machine body in hilly and mountainous areas, an automatic leveling control system of the transplanting machine body is designed, which is composed of a state measurement unit, a single-chip embedded system and an electric drive system. First, considering the advantages and disadvantages of position error leveling and angle error leveling, a multi-sensor coupling leveling strategy is proposed. Secondly, the fuzzy PID controller is used to control the electric push rod in the actuator, and the Kalman filter is used to filter out the engine vibration interference from the transplanter chassis. Then, the fuzzy PID controller and Kalman filter designed are simulated and analyzed by MATLAB/Simulink. The simulation results show that under the same initial parameters, fuzzy PID control has better control performance than traditional PID control. The system adjustment time is reduced by 62.86%, the rise time is reduced by 47.64%, the peak time is reduced by 45.54%, and the maximum overshoot is reduced by 12.23%. Kalman filter can effectively suppress interference and jitter signals. Finally, the static and dynamic tests are carried out for the automatic leveling control system of the car body. The test results show that the adjustment time of the automatic leveling system is less than 3.5 s and the maximum leveling error is less than 0.5° when the vehicle body tilt angle is within-8°～8°. When the transplanter is running at a speed of 3.6 km/h, the vehicle body tilt angle is controlled within ±3° under the road with large undulation, and the vehicle body tilt angle under the road with small undulation is basically maintained at 0°. The leveling speed is fast and the effect is good, which is of great significance to improve the transplanter’s transplanting effect.