农机导航自校正模型控制方法研究

Self-tuning Model Control Method for Farm Machine Navigation

针对运动学模型中的近似条件对模型控制方法曲线路径跟踪精度的影响,提出了一种农机导航自校正模型控制方法。该方法采用模型控制方法设计控制律,并采用模糊控制方法自适应地在线调节模型控制律的控制量。农业机械的路径跟踪实验结果表明,该方法既保留了模型控制方法在直线路径跟踪方面的优点,又弥补了模型控制方法在曲线路径跟踪方面的缺陷。当速度为1.0 m/s时,直线路径跟踪最大横向偏差小于0.064 9 m,曲线路径跟踪的最大横向偏差小于0.185 7 m。

In order to improve the precision of path tracking, a self-tuning model control method for farm machine navigation was presented. The thought of the two-level control was induced to design the navigation controller. As the first level controller, the nonlinear kinematics model and feedback linearization theory were used to design the control law, and counting formula of the system controlling quantity was given. In order to solve the imprecision problem of the nonlinear kinematics and improve the stability of the navigation system, a second level controller was needed. As the second level controller, the fuzzy controller used the fuzzy control method to adjust system control quantity of model controller online and adaptively. The results of the path tracking experiment for the agricultural machine showed that the control method kept the advantages of model controller for tracking the straight and solved the problems of model controller in a curved path tracking. When it ran at the speed of 1.0 m/s, the maximum lateral deviation of straight path tracking was less than 0. 064 9 m, the maximum lateral deviation of curved path traced was less than 0. 185 7 m.