Active compensation of the movement inaccuracies of feed drives with profiled rail guides based on high dynamic piezo actuators

到目前为止，流体动力和磁性直线制导系统在高精度应用中比线性型轨导轨更受欢迎，因为这些制导系统具有高运行精度、高阻尼能力、高刚性和无粘滑效应和缺陷。而型材导轨构造相对简单，不需要昂贵和复杂的附加骨料，因此它们可以非常经济有效地使用。型材导轨的缺点是，其非线性刚度主要由滚动接触条件决定，而这些条件由于滚动体的动态再循环而周期性变化。轮廓导轨的不同位移部分的总和导致进给传动的不准确性。特别是自激励和分离激励引起的动态刚度可高达静态刚度的171倍，这也是由于阻尼能力低，阻尼系数为d=0.001至d=0.01。在没有单独激励（行程脉动）的情况下，周期运动的不准确性可达1µm。为了减少振动刺激和冲程脉动，异形导轨仅用于高精度应用（适合特殊应用的几何优化入口区域），并带有滚珠链和额外的阻尼导轨。静态位移和动态位移的问题不能完全解决，特别是对于可变的工艺参数。其原因是非线性滚动接触中速度和载荷的影响。在机械工程中，异形导轨作为一种研究充分、用途广泛的标准部件，具有众多的应用优势，但目前还没有主动的程序来补偿运动误差。拟议的研究项目希望提供新的基本见解，如何与轮廓导轨进给驱动器的运动精度可以主动提高，以便在精度要求较低的微米甚至纳米范围内的高精度应用中使用它们，并使它们与静压和磁制导系统竞争。因此，基于数学等效机械振动系统的关于型轨导轨动态描述的已知理论见解，以及基于滚动接触中的赫兹位移和导轨架和导轨的弹性变形的静态载荷-位移模型，与关于滚动元件、导轨架和附加组件的真实动态行为的新研究见解相结合。在此基础上，将开发一个基于压电致动器的基于模型的运动误差实时补偿系统。

So far, hydrodynamic and magnetic linear guidance systems are preferred over linear profiled rail guides at high precision applications, because these guidance systems have a high running accuracy, a high damping capacity, a high rigidity and they are free of stick- slip effects and ware. Whereas profiled rail guides are constructed relatively simple, don’t need expensive and complex additional aggregates and therefore they can be used very cost-efficiently. The deficit of profiled rail guides is, that the nonlinear rigidity is dominated by the conditions in the rolling contact and these conditions change cyclically due to the dynamic rolling element recirculation. The sum of different displacement parts of the profiled rail guides lead to inaccuracies in feed drives. Especially the dynamic rigidity, caused by self- and separate excitation, can be up to 171 times higher than the static rigidity, also because of the low damping capacity with damping factors of d=0.001 to d=0.01. The part of cyclical movement inaccuracies without separate excitation (stroke pulsation) can be up to 1 µm. Profiled rail guides are only used as a custom-built in high precision applications (geometric optimized inlet areas that are adapted to special applications) with ball chains and additional damping guides, in order to reduce vibration stimulation and stroke pulsation. The problem of static and dynamic displacements cannot be solved, especially not for variable process parameters, completely with that. The Reason for this are velocity- and load-dependent effects in the nonlinear rolling contact. For profiled rail guides as a well-researched and versatile applicable standard component in mechanical engineering with its numerous application benefits, there is no active procedure to compensate movement inaccuracies.The proposed research project wants to provide new fundamental insights on how the movement accuracy of feed drives with profiled rail guides can be improved actively, in order to use them in high precision applications with accuracy requirements in the lower micrometer or even nanometer range and make them competitive to hydrostatic and magnetic guidance systems. Therefore the known theoretical insights about the dynamic descriptiveness of profiled rail guides, based on a mathematical equivalent mechanical vibration system, and the static load-displacement-model, based on the Hertzian displacements in the rolling contact and the elastic deformation of the guide carriage and the guide rail, are combined with new investigated insights about the real dynamic behavior of the rolling elements, the guide carriage and additional assemblies. Building on this, a real-time capable system for a model-based compensation of movement inaccuracies, based on piezo actuators, will be developed.