重型数控机床热误差监测与实时补偿新方法研究

As core equipment in high-end manufacturing field, the accuracy of heavy-duty CNC machining has always been concerned by academia and industry. Due to the significance of action, complexity of thermo-mechanical coupling and randomness of temperature disturbance, the thermal error which has become an international research hot spot in many factors which influence the accuracy of the heavy-duty CNC machine tools. Facing the complex instructures and multiple heat sources of heavy-duty machine tools and the chanllenge of multipoint and multifield,the proposal will research on the following aspects to satisfy the urgent requirements of thermal error monitoring and compensating. Firstly an approach to distributed temperature measurement and monitoring criteria are studied and a new method and theory are built up; secondly the mapping relationships and the transfer mechanisms between the temperature field and thermal errors of machine tools based on exploring the law of the multiple heat sources and the thermal errors; thirdly a method for thermo-mechanical decoupling and the general model about predicting thermal errors based on the data of monitoring temperature of some key points on machine tools is presented according to the accumulative mathematical model of thermo-mechanical coupling and thermal error transfer; at last a system is built up, which is able to monitor the thermal errors and compensate in real time, on the basis of studying on the method of embedded real-time compensation. The achievement will pioneer a new efficient way and will be used as a significant technology to support monitoring the thermal errors and compensating in real time for modern manufacturing systems.

作为高端制造业的核心装备，重型数控机床的加工精度历来备受学术界和产业界的关注。影响重型数控机床精度的众多因素中，热误差以其作用的显著性、热-力耦合的复杂性以及扰动因素的随机性成为国际机械学科研究的热点。本项目面向高精度重型数控机床热误差监测与补偿的迫切需求，针对重型机床结构与热源复杂、多点多场监测以及温度随机扰动补偿困难的难题，研究1）重型数控机床发热行为、零部件热变形机理及热误差成因；2）面向重型数控机床的高精度光纤光栅温度测量方法与分布式测量准则；3）基于测量数据的温度场重建方法、温度（温度场）-热误差映射关系与重型数控机床热误差预报通用模型；4）基于嵌入式技术的实时补偿方法，建立一套重型数控机床的热误差监测与实时补偿系统，形成基于光纤光栅传感的重型机床热误差监测与基于嵌入式技术的实时补偿新原理和新方法。研究成果可为现代制造系统热误差监测与实时补偿提供重要技术支撑和开辟新的有效途径。

高性能的重型数控机床是国民经济和国防建设的基础性和战略性装备。热误差是制约重型数控机床加工精度的最重要因素。减小重型机床热误差，提高其加工精度对我国基础工业的发展具有重要的战略意义与重大的经济价值。.本项目围绕重型数控机床结构及传热机理的复杂性和现有热误差监测与补偿手段的局限性等问题，提出了面向重型数控机床的基于光纤光栅传感的热误差监测与基于嵌入式技术的热误差实时补偿的新原理和新方法。重点研究了重型数控机床发热行为、零部件热变形机理及热误差成因，特别是理论与实验研究了重型数控机床主轴在不同轴承预紧力、转速、切削力和轴承安装误差的热误差特征，建立了重型数控机床大型结构件在环境温度、内部热源作用下的动态温度场模型与动态热变形模型。研发了面向重型数控机床的光纤光栅系列传感器和多通道多物理参数大容量光纤光栅解调系统，研究了高精度光纤光栅表面温度测量方法，提出了重型数控机床温度场光纤光栅分布式测量的布点优化策略与相关准则，建立了基于光纤光栅传感的重型数控机床热误差监测系统。研究了基于光纤光栅分布式测量数据的重型数控机床温度场重建方法，建立了基于数据驱动的重型数控机床热误差通用预测模型，包括热误差滞后模型，多元线性回归模型和卷积神经网络模型。研究了基于G代码参数嵌入式热误差补偿的原理与方法，研发了基于嵌入式热误差实时补偿控制器，完成了基于光纤光栅的热误差监测系统-基于嵌入式技术的热误差实时补偿系统-机床数控系统三大系统的科学集成，构建一个面向重型数控机床的基于光纤光栅传感的热误差监测和基于嵌入式技术的实时补偿系统。.这项研究为现代制造系统热误差监测与实时补偿提供了重要技术支撑和开辟了新的有效途径。研究成果对提高现代数控加工系统的精度、生产效率和可靠性具有十分重要的理论和实践意义。