Path tracking control method and performance test based on agricultural machinery pose correction

The annual rice planting area in China is approximately 30 million ha. With continuous reductions in the rural labour force and increasing production costs, it is urgent to develop unmanned technology for paddy field agricultural machinery to solve the problem of "who will farm the land". In paddy field environments with slippery mud and uneven hard underlying, side slip and slip of paddy farm machinery can easily occur. Due to the relative movement and attitude changes between paddy farm machinery and implements and the inconsistent driving track of the farm machinery and implements, it is difficult to track and control the path of unmanned paddy farm machinery. In view of the above problems, this paper takes the paddy field agricultural machinery body as the control object and the agricultural machinery pose as the observation quantity and establishes an agricultural machinery kinematics model based on agricultural machinery pose correction. Based on the model and model predictive control (MPC), the linear model, objective function and constraint function of paddy field agricultural machinery are designed, an MPC path tracking control method is established based on the pose of the agricultural machinery, and field experiments are conducted. The results show that the average root mean square error of the three-line straight-line path tracking is 0.043 m, the average absolute error is 0.033 m, and the effect is favourable. The MPC path tracking method based on the pose correction of agricultural machinery can effectively suppress abrupt lateral position deviations caused by the relative position and attitude changes of the machine, can improve the control accuracy, and can meet the control accuracy requirements of unmanned paddy field agricultural machinery operations.