基于高增益观测器的挖掘机工作装置滑模控制  

High-gain observer-based sliding mode control for hydraulic excavators

作　　者：徐国胜[1] 於祖庆[1] 陆念力[1] 吕广明[1] XU Guosheng;YU Zuqing;LU Nianli;LYU Guangming(School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China)

机构地区：[1]哈尔滨工业大学机电工程学院,黑龙江哈尔滨150001

出　　处：《哈尔滨工程大学学报》2021年第6期885-892,共8页Journal of Harbin Engineering University

基　　金：国家自然科学基金青年基金项目(11802072).

摘　　要：为了提升挖掘机自动化水平,减少传感器使用数量,节约控制成本,本文设计了基于高增益观测器的滑模控制器,控制挖掘机铲斗轨迹。建立了挖掘机关节空间与驱动空间位移、速度与力之间的关系,对挖掘工况中常见的以定切削角直线整平作业进行了轨迹规划,并得到相应驱动空间中液压缸杆位移规划曲线。以伺服阀输入电压为控制输入,建立了挖掘机驱动空间,即伺服液压系统数学模型。其次在匹配不确定性与非匹配不确定性存在条件下,采用基于高增益观测器的滑模控制使液压缸杆位移跟踪规划值,并基于奇异摄动理论证明了闭环控制系统的稳定性。相较于以挖掘机关节转矩为控制输入,本文采用伺服阀电压作为控制输入更为直接且易于实践。采用高增益观测器对状态观测,可减少传感器的使用数量,节约整机控制成本。控制器的设计对一类问题具有广泛意义且从理论上证明了复合控制系统稳定性。To improve the automation level of excavators,reduce the number of sensors used for control,and save control cost,a sliding mode controller based on high-gain observers is designed in this work to control the trajectory of the digging bucket.First,the relationship of the displacement,speed and force between excavator joint space and driving space is established.Trajectory planning is performed for common leveling operations with fixed cutting angles,and the displacement planning curve for the hydraulic cylinder corresponding to driving space is obtained.The input voltage of the electro-hydraulic servo valve is taken as the control input and a servo-hydraulic system mathematical model of excavator driving is established.Then,under matched and mismatched uncertainty,the high-gain observer-based sliding mode control(HOSMC)method is applied to determine the trajectory of the hydraulic cylinder to track the planning value.Finally,the stability of the closed-loop control system is analyzed through the singular perturbation method.The design of the HOSMC is significant to a class of problems.The simulation results show that the proposed controller is effective.

关 键 词：挖掘机 滑模变结构 高增益状态观测器 液压缸 奇异摄动 轨迹规划 非匹配不确定 匹配不确定 

分 类 号：TU621[建筑科学—建筑技术科学]