压电驱动快刀伺服系统的复杂轨迹跟踪控制

Fast tool servo (FTS) technology is one of the most promising ultra-precision machining technology. During the manufacturing process, the FTS system is commanded to track the motion of the processed workpiece. To meet the particular servo challenges on the analysis, modeling and control of large deformation compliant mechanisms based FTS supporting high performance manufacturing, this research will investigate the mathematical modeling approach from the perspectives of compliant mechanisms and rigid-flexible coupling, and extend the repetitive structure based tracking control theory to better capture the dynamical characteristics of the tracking reference signals. With consideration of the time delay of sensors and actuator saturations, this research will further explore the structure modification of the repetitive controller and anti-windup compensation methods, in order to realize the optimizations of the tracking, robustness, disturbance rejection and saturation compensation performances under a unified control framework, such that the dynamic tracking performance of FTS systems can be further improved. The primary goal of this research is to develop a comprehensive analysis, modeling and tracking control methodology of FTS specifically for ultra-precision machining applications. The research outcomes of this project will provide theory and technical support for design and development of FTS systems, which contributes to the extreme manufacturing at the nanoscale.

快刀伺服技术是最有发展前途的超精密加工技术之一，其工作过程实质上就是快刀伺服装置驱动刀具相对工件运动的跟踪过程。本项目针对快刀伺服系统在轨迹跟踪模式下柔性机构大挠曲变形、系统建模以及高动态精度轨迹跟踪控制等突出存在的伺服挑战，通过对柔性机构变形机理的研究和刚柔耦合分析建立更有效的数学模型，并充分利用被跟踪信号的周期频率特性拓展基于重复控制的输出调节控制理论，探索面向传感器延迟和执行器饱和的重复控制器结构改进和抗饱和补偿方法，研究统一控制框架下跟踪性能、鲁棒性能、抗干扰性能和饱和补偿性能的优化设计，综合提升快刀伺服系统的动态跟踪性能。在此基础上，形成一套面向超精密加工应用的快刀伺服系统建模和控制方法，为我国快刀伺服系统的设计和开发提供理论支撑和技术支持，为实现纳米极端制造打下良好基础。

快刀伺服技术是光学自由曲面、微纳结构功能表面等超精密零件加工的重要使能技术，具有巨大的研究价值和产业意义。本项目针对压电驱动快刀伺服系统超高运动精度和复杂轨迹跟踪等突出存在的伺服挑战，从柔性机构的变形机理入手，深入研究了基于弹性梁理论、伪刚体方法和刚柔耦合分析的柔性机构静力学和动力学建模方法，设计了基于输入输出导向和三维正交桥式放大的高动态快刀伺服系统，提出了基于磁流变弹性体智能材料的快刀伺服刚度自适应调节设计。利用被跟踪信号的周期频率特性，研究了重复控制在快刀伺服系统运动控制下的拓展，提出了基于局部频率整形优化和干扰观测的改进重复控制结构，探索了模型不确定性下的控制器H∞优化设计方法，综合提升了快刀伺服系统的超精密跟踪和抗干扰性能。针对大行程跟踪下的执行器饱和问题，进一步研究了快刀伺服系统抗饱和补偿优化设计方法，提出了基于重复控制的超前抗饱和跟踪控制结构，在执行器饱和实际发生之前激活抗饱和补偿器对系统输出和控制输出进行调节，提高了快刀伺服系统暂态性能和鲁棒稳定性，在有限刚度范围内实现高速高精度跟踪的优化设计。在上述理论研究的基础上，搭建了MATLAB/SIMULINK的快刀伺服系统控制算法快速成型实验系统，完成了控制算法的实时应用和验证，实现了对复杂加工环境下快刀伺服系统跟踪运动的优化。基于上述研究，形成了一套面向超精密加工应用的快刀伺服系统建模和控制方法，可为基于快刀伺服技术的纳米极端制造提供理论支撑和技术支持。