Basics for structure integrated measurement und control integrated processing of spatial forces and moments in machine tools

在许多与生产相关的应用中，如过程监控或闭环过程控制，越来越需要在线力测量。随着现代机床的高机动性，如五轴机床或六足机，需要测量高达6 DOF的空间TCP力和力矩。到目前为止，大多数6 DOF力板使用和安装接近TCP。由于该地区环境条件恶劣，有必要采取周密的防护措施。此外，工作空间将减少，以及机器的坚固性，至少力板是不成比例的昂贵。由于诸如摩擦等许多干扰影响，从驱动电流中估计力无法达到令人满意的测量精度。在机器结构中集成单轴力传感器在成本方面具有很高的潜力。该项目的主要目标是提供一个空间TCP力和力矩测量和闭环控制系统，使用结构集成单轴力传感器作为力板的经济替代品。在项目的第一部分中，针对不同的测量配置，评估了传感器在机器结构中的集成、静态测量模型和参数识别以及机器控制系统中的模型集成。第二部分对基于动态测量和动态轨迹的参数辨识进行了研究，并对基于集成传感器的力控制进行了概念验证。对所有变异进行了广泛的实验研究。结构集成力测量的最大潜力在于其在力控制方面的应用，这是该项目继续进行的主要目标。在第二部分中对基于集成传感器的力控制概念进行了基本证明之后，进一步项目的方法是克服当前异步设定点，非线性机器刚度，力控制过程中的尺寸精度以及力控制实际过程（如铣削）的缺陷。因此，迫切需要进行研究，特别是与结构集成传感器有关的研究。这些工作包括在一条G-Code线上开发力和位置控制的同步设定点，允许在过程中改变力和力方向，评估与姿态相关的空间机器刚度的建模和校正，这可能影响力控制的稳定性，以及评估接触建模，接触搜索和在力控制期间实现尺寸精度。

Online force measurement is increasingly required in many production-related applications, like process monitoring or closed loop process control. With the high mobility of modern machine tools, as five axis machines or hexapods, measuring spatial TCP forces and moments in up to 6 DOF is required. Thus far mostly 6 DOF forces plates are used and mounted close to the TCP. Because of harsh environment conditions in this area elaborate protective measures are necessary. Furthermore the workspace will be reduced as well as the machines sturdiness and at least forces plates are disproportionately expensive. With estimating forces from drives currents a satisfying measuring accuracy cannot be achieved for machine tools because of numerous interfering influences like frictions.The integration of single-axis forces sensors in the machine structure presents high potential with regard to the costs. Main objective of the project is to provide a spatial TCP forces and moments measurement and closed loop control system with the use of structure integrated single-axis forces sensors as an economic alternative to forces plates. In the first part of the project the integration of sensors in machine structures, static measurement models and parameter identification as well as the model integration in machine control systems has been evaluated for different measurement configurations. In the second part dynamic measurement and dynamic trajectory based parameter identification was studied as well as a proof of concept for a force control using integrated sensors. For all variants extensive experimental studies were performed.The biggest potential for structure-integrated force measurement has its application in force control, which is the main objective within the continuation of the project. After a basic proof of concept of a force control based on integrated sensors in the second part, the approach for the further project is overcoming the current deficits of asynchronous set points, nonlinear machine stiffness, dimensional accuracy during force control as well as force controlled practical processes, such as milling. Thereby a significant need for research exists, especially relating to structure-integrated sensors.The works include the development of synchronous set point provision for force and position control in one G-Code line, which allows a variation of force and force direction during the process, evaluations concerning modelling and correction of the pose-dependent spatial machine stiffness, which can influence stability in force control as well as evaluations of contact modelling contact search and achieving dimensional accuracy during force control.