采用RBF网络的喷雾机喷杆自适应动态面跟踪控制

Adaptive RBF-Network Dynamic Surface Tracking Control of Sprayer Boom Systems

为了实现喷雾机喷杆快速而准确地伺服跟踪农作物冠层高度,选用电液伺服系统作为其位置调节装置,系统建模以喷雾机喷杆为负载的电液伺服系统.首先,充分考虑系统的强非线性和参数不确定因素,建立完整的数学模型;然后,采用动态面方法设计控制器,通过RBF网络对不确定项和非线性函数进行逼近,在控制律中加入阻尼项补偿干扰对系统性能的影响;基于Lyapunov稳定性方法,证明闭环系统信号最终一致有界;最后,对某喷雾机喷杆系统进行仿真验证,结果表明设计控制器具有良好的仿形跟踪控制性能.

To realize fast and accurate servo tracking of the canopy height, an electro-hydraulic servo system was used for the position adjustment device. The electro-hydraulic servo system was modeled with the load of the sprayer boom. First, the strong non-linearity and parameters’ uncertainties were well considered and the complete system model was built, and the controller was designed with the dynamic surface control method. Then the RBF network was used to approximate the non-linearity and uncertainty functions, the control law was applied with damping terms to compensate for the disturbance influences on the system, and all the signals in the closed loop system were proved to be uniformly bounded based on the Lyapunov stability method. Finally, simulation and verification of a sprayer boom with the electro-hydraulic servo system were conducted. The results show that the designed controller has good copy tracking performances.