Non-Contact Micro-Manipulation with Air Gap Control Type Magnetic Levitation System

以微操纵为目标，研究了悬浮力可通过运动控制方法调节的非接触式磁悬浮机构。这个项目分为两个研究。一种是针对多自由度悬浮的操纵控制，另一种是针对微悬浮系统。我们对项目期间的各项研究结果进行了如下验证。通过基本的数值模拟，验证了二自由度悬浮系统的可行性。在此基础上，设计并制作了第一个由两个永磁体和驱动器组成的2自由度悬浮系统原型。然而，该系统的实验测试失败了。估计这一结果是由磁体的引力误差引起的，因此用有限元方法对磁体的引力进行了分析。作为结果，我们验证了磁体的排列会影响力，并且很难使该系统稳定，因为力会根据物体的位置敏感地变化。研究结果表明，采用反馈控制的方式，三永磁体和执行器组成的系统易于稳定。制作了第二套样机并进行了测试。2自由度悬浮成功。运动幅度为4mm，频率响应为4hz。在微悬浮研究中，主要考察悬浮物体较小时的稳定性。结果表明，当控制器为数字控制器时，输出滤波器是必要的。在此基础上，制作了采用压电作动器的悬浮系统原型。实验检验表明，使直径为2mm的铁球悬浮是可能的。

For the aim of micro-manipulation, we investigate noncontact magnetically levitation mechanisms whose suspension forces are adjusted by motion control methods. The project divided to two studies. One is aiming at multi-DOF control of levitation for manipulation, and the other is aiming at micro levitation system. We verify the following results about each study in the term of this project.The possibility of 2 DOF levitation system is examined by basic numerical simulations. Based on the results, a first prototype 2 DOF levitation system which has two permanent magnets and actuators is designed and made. The experimental examination on this system, however, failed. As this result is estimated to be caused by the errors of the attractive forces of magnets, the attractive forces are analyzed by a FEM method. As the results, we verified that the arrangement of magnets affects the forces and it is very difficult to make this system stable because the forces are changed sensitively according to the position of the object. And we found the results that system with three permanent magnets and actuator can be stable easily by feedback control. The second prototype system are made and examined. 2 DOF levitation succeeded. The magnitude of movement 4 mm and frequency response 4 Hz were achieved in the examinations.In micro-levitation study, the stability is examined when the levitation object is smaller. As the result, it is obtained that the fast response are required to actuators and if the controller is digital one, the output filter is necessary. Based on the results, a prototype levitation system which uses the piezoelectric actuators is made. The experimental examination shows that it is possible to levitate an iron ball with 2 mm diameter.