Study of H_* Control for 4WD Tractor-Implement Systems

本文的研究目标是拖拉机-机具系统的鲁棒控制器设计。研究工作分为四个方面：（1）田间作业条件下包括内部转动部件在内的拖拉机-机具系统数学模型的建立; (2)田间试验和分析;（3）拖拉机-机具系统参数辨识试验;（4）拖拉机-机具系统鲁棒控制器设计分析。(1)拖拉机-机具系统在耕作作业中的动力学特性拖拉机-机具系统在耕作作业中一般是在重载工况下工作的。我们进行了不同条件下拖拉机-悬挂系统耕作作业的田间试验。分析这些数据，我们制定了数学模型的TIS在现场操作条件下。该模型包括两个内部旋转 ...更多信息 和平移运动，并表示系统的反馈控制特性。(2)拖拉机执行器系统的参数识别为了阐明TIS的整体行为，不可避免地需要了解两个参数。然后执行参数识别测试。其中一个参数是一对时间常数，表示扭矩-燃料关系和系统的动态特性。另一个是发动机-传动系统的粘性系数。引入非线性响应面方法来辨识这些参数。(3)拖拉机-机具系统的鲁棒控制器设计分析针对拖拉机-机具系统的非线性，提出了一种由H_*00鲁棒控制构成的控制器设计方法。由于拖拉机-机具系统在耕作作业中受到扭矩扰动的影响，因此，轮胎转速控制的稳定性在耕作作业中至关重要。首先，我们将鲁棒控制系统的混合灵敏度方法应用于TIS，得到了H_* 控制器的集合。其次，我们用所提出的H_* 控制器代替机械调速器设计了TIS的反馈控制。TIS的动态特性得到了很大的改善。少

The objective of this research work is the robust controller design for tractor-implement system. The research work is divided into four categories (1) Formulation of mathematical model of tractor-implement system (TIS) under field operation condition including internal rotating parts of the system. (2) A field experiment with a tractor-implement system tinier tillage operation and its analysis, (3) A parameter identifiction laboratory test with the tractor-implement system, and (4) Robust controller design analysis with the tractor-implement systeim.(1) Dynamical characteristics of the tractor-implement system under tillage operationsGenerally a tractor-implement system works in heavy-duty conditions under tillage operations. We executed the field experiments for tillage operations with the tractor-impliment system under various conditions. Analyzing these data, we formulated a mathematical model for the TIS under field operating conditions. The model includes both internal rotational … More and translational motions and represents the feedback control characteristics of the system.(2) Parameter identification of the tractcr-implement systemFor the clarification of the TIS overall behaviors, the knowledge of two parameters is inevitable. We then execute the parameter identification test. One of the parameter is a pair of time constant that represents the torque-fuel relationship and dynamics of the system. The other is the viscous coefficient of the engine-transmission system. A nonlinear RSM method was introduced to identify these parameters.(3) Robust controller design analysis with the tractor-implement systemTalking account of the nonlinearity of the tractor-implement system(TIS), we propose a controller design method which consists of H_*00 robust control. As the tractor-implement system under tillage operation is heavily influenced by the torque disturbances, the stability of tire speed control is essentially important in tillage operations. First, we applied the Mixed-Sensitivity approach of the robust control system for the TIS and obtained the set of H_* controller Second, we designed the feedback control of the TIS using the proposed H_* controller instead of the mechanical govemor. The dynamic characteristics of the TIS are greatly improved. Less