School of Mechanical Engineering, 12579Southeast University, Nanjing, China.
Nanjing Institute of Agricultural Mechanization, 12661Ministry of Agriculture and Rural Affairs, Nanjing, China.
Sci Prog. 2021 Oct;104(4):368504211053728. doi: 10.1177/00368504211053728.
Agricultural machine automatic navigation poses great challenge to the precise agricultural technology system nowadays. To this end, this paper proposes a novel steering assistance system (SAS) to assist drivers in the path-tracking. First, the driver steering model is investigated through the driver simulator tests. Combining the wheeled tractor kinematics model, a driver-vehicle model is developed. Then, a polytopic linear parameter-varying (LPV) system is adopted to describe the uncertainties, including time-varying driver model parameters and velocity, in the model, based on which an output-feedback robust controller is developed to ensure robust stability within the polytope space. Moreover, a regional pole placement method is adopted to improve the transient performance of the system. Finally, driver-in-the-loop and field tests conducted to value the controller. The results show the effectiveness of the proposed method to improve the path-tracking performance for the agricultural machine navigation, while reducing the physical and mental workload of drivers. This control method is expected to be a paradigm for the precise navigation system of the agricultural machinery.
农业机械自动导航对当今精确农业技术系统提出了巨大挑战。为此，本文提出了一种新的转向辅助系统（SAS），以协助驾驶员进行路径跟踪。首先，通过驾驶员模拟器测试研究驾驶员转向模型，结合轮式拖拉机运动学模型，开发了驾驶员-车辆模型。然后，采用多面体线性参数时变（LPV）系统来描述模型中的不确定性，包括时变驾驶员模型参数和速度，在此基础上，开发了输出反馈鲁棒控制器，以确保在多面体空间内的鲁棒稳定性。此外，采用区域极点配置方法来改善系统的瞬态性能。最后，进行驾驶员在环和田间测试以评估控制器。结果表明，该方法可有效提高农业机械导航的路径跟踪性能，同时降低驾驶员的身心工作负荷。这种控制方法有望成为农业机械精确导航系统的范例。
