机床伺服进给系统精细化摩擦建模与补偿技术研究

With the development of precision and ultra-precision machining technology, China's demand for high-end CNC machine tools is increasing, and its positioning accuracy and other performance requirements are increasingly stringent. Nonlinear friction is the main factor affecting the positioning accuracy of CNC machine tools. Friction compensation control has become the main technology to improve the positioning accuracy of CNC machine tools. At present, the integrated friction model is widely used in friction compensation control, which does not take into account the difference between the ball screw and the linear guide friction model, and does not establish the association between the weight change of the workpiece and the friction parameter. The friction compensation effect is seriously affected. This paper starts from the analysis of the friction mechanism between the ball screw and the linear guide, and the difference of friction characteristics of each component are taken into account. The friction parameter of the ball screw and the linear guide are respectively identified, and establish the fine friction model of the servo feed system. Considering the effect of load on the friction parameters, the load estimator is designed to estimate the load of the table and construct the friction observer with load estimator. And this paper will propose a composite friction compensation strategy integrating friction Observer, Extended State Observer and High - order Sliding Mode Control. The research of this project will provide the theoretical basis and technical support for the fine friction modeling and compensation of high precision CNC machine tools.

随着精密与超精密加工技术的发展，我国对高档数控机床的需求日益增大，对其定位精度等性能要求也日益严格。非线性摩擦是影响数控机床定位精度的主要因素，摩擦补偿控制已经成为提高数控机床定位精度的主要技术。目前摩擦补偿广为采用的是将伺服进给系统作为整体进行集中辨识的集成摩擦模型，该模型并未考虑滚珠丝杠与直线导轨摩擦模型的差异，且未建立工件重量变化与摩擦参数的关联，严重影响了摩擦补偿效果。本项目从分析滚珠丝杠与直线导轨产生摩擦的机理入手，计入各组件摩擦特性的差异，对滚珠丝杠与直线导轨分别进行摩擦参数辨识，建立伺服进给系统的精细化摩擦模型；考虑负载对摩擦参数的影响，设计负载估计器对工作台负载进行实时估计，构建含有负载估计器的摩擦观测器；提出集成摩擦观测器、扩张状态观测器和高阶滑模控制器的复合摩擦补偿策略。本项目的研究将为高档精密数控机床的精细化摩擦建模与补偿提供理论基础和技术支撑。

随着精密与超精密加工技术的发展，我国对高档数控机床的需求日益增大，对其定位精度等性能要求也日益严格。非线性摩擦是影响数控机床定位精度的主要因素，摩擦补偿控制已经成为提高数控机床定位精度的主要技术。目前摩擦补偿广为采用的是将伺服进给系统作为整体进行集中辨识的集成摩擦模型，该模型并未考虑滚珠丝杠与直线导轨摩擦模型的差异，且未建立工件重量变化与摩擦参数的关联，严重影响了摩擦补偿效果。本项目从分析常规的滚珠丝杠与直线导轨产生摩擦的机理入手，计入各组件摩擦特性的差异，对滚珠丝杠与直线导轨分别进行摩擦参数辨识，建立常规滚珠丝杠伺服进给系统的精细化摩擦模型；考虑负载对摩擦参数的影响，设计负载估计器对工作台负载进行实时估计，构建含有负载估计器的摩擦观测器；提出集成摩擦观测器、扩张状态观测器和高阶滑模控制器的复合摩擦补偿策略；突破传统滚珠丝杠进给系统的局限，基于螺母驱动型滚珠丝杠，提出宏宏双驱动进给系统，提出了不使用力传感器的精细化摩擦辨识方法与摩擦补偿控制策略；考虑丝杠-滚珠-螺母摩擦生热效应，基于神经网络建立了宏宏双驱动进给系统的热误差补偿模型。本项目汇总的研究成果专著《微纳运动实现技术》编入了丁汉院士牵头的《智能制造与机器人理论及技术研究丛书》，使用本项目的研究为高档精密数控机床的精细化摩擦建模与补偿提供理论基础和技术支撑，本项目发表的论文与申请的发明专利对滚珠丝杠伺服进给系统的设计具有重要的参考价值。