纳米精度运动中的多自由度串扰分析与精细解耦控制研究

The moving structure with the combination of rough moving of long stroke but low accuracy and fine moving of short stroke but high accuracy is mainly adopted to achieve the nanometer accuracy and long stroke moving. In such moving stage, the nanometer moving accuracy of six-degree-of-freedom are completely achieved by the moving of fine stage. Due to the inevitable manufacturing tolerances, the undesired forces/torques always are generated that is caused by the deviation of both the center of mass of the fine stage, and the point and direction of the force applied. Usually, the multi-dimension Lorenz motor would generate the distrubed driving forces/torques in the undesired moving directions, beside the driving forces/torques in the desired moving directions. When the fine stage is moving, the relative positions of the coils array and magnetic array are always changed, and as a result, the undesired dynamic side forces/torques also can be produced. Moreover, the couple interactions of two or more near coils would be generated when the currents flow the coils. These lead to the complex cross-talk couple effects, and it also is the most important factor to reduce the nanomter moving accuracy. Focused on this problem, the cross-talk couple existed in multi-degree-of -freedom stage moving will be analyzed and compensated in our future research for this project. It contains the following aspects. The first aspect is to investigate both static cross-talk couples and dynamic cross-talk couples, and then study the interacting principle of the two kinds of cross-talk couple on the nanometer moving accuracy. Based on this principle, the methods that are used to identify cross-talk couples are proposed. The practical test of both the static couples and the dynaic couples are addressed. The special algorithms are proposed, and the relevant software are designed and developed, which provides the theoretical methods and the software tools that can be used for the analysis and test for the couples. And the compensation models will be further put forward. Thus, the theoretical approaches and the software tools are all provided which can be used for research of nanometer moving accuracy.

大行程纳米精度运动系统采用粗-精复合运动结构，并由六自由度微动平台生成纳米精度。由于制造装配误差，平台质心以及电机力作用点与作用方向偏差产生附加力/力矩；洛伦兹电机除产生期望驱动力外还将产生异于运动方向的干扰力；运动中电机线圈与磁钢相对位置倾斜变化时产生动态侧力；驱动线圈相邻较近时亦将产生耦合感应；上述干扰力/力矩对悬浮的微动平台形成复杂的多自由度耦合串扰，它是影响纳米级运动精度的核心。对此，开展多自由度运动串扰的分析与补偿研究：1）研究六自由度静、动态串扰以及多重串扰的影响规律；2）研究多维串扰解耦分离与识别方法；3）研究静、动态串扰的测试方法及其串扰分析与解耦分离算法软件，为精密运动测试分析提供原理方法与分析工具；4）研究补偿模型与实时补偿控制算法，为纳米级超精密运动控制提供理论方法与软件基础。

多自由度串扰耦合普遍存在于精密制造装备中，是大形程、纳米精度运动中的关键问题。本项目研究了粗-精复合运动结构中的六自由度微动平台的串扰耦合规律及其精细解耦控制方法。重点针对实际制造中的制造装配误差所引起的平台质心以及电机力作用点与作用方向偏差产生的附加力/力矩、洛伦兹电机除产生期望驱动力外所产生的异于运动方向的干扰力、台体运动中的电机线圈与磁钢相对位置倾斜变化时产生的动态侧力、驱动线圈相邻较近时产生的耦合感应，深入分析了上述干扰力/ 力矩对悬浮的微动平台形成复杂的多自由度耦合串扰影响规律及其精细解耦补偿策略，主要包括：1）研究了六自由度静、动态串扰以及多重串扰的影响规律；2）研究了多维串扰解耦分离与识别方法；3）研究了静、动态串扰的测试方法及其串扰分析与解耦分离算法软件，为精密运动测试分析提供原理方法与分析工具； 4）研究了补偿模型与实时补偿控制算法。实际测试结果为：定位精度<3nm，两台同步跟踪平均误差MA<1.5nm，均方差MSD<4nm（上述误差均为 3σ）。该项研究为大行程、纳米级超精密运动控制提供了理论方法与基础。