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

以微操作为目的，研究了通过运动控制方法调节悬浮力的非接触式磁悬浮机构。该项目分为两项研究。一种是针对操纵的多自由度悬浮控制，另一种是针对微悬浮系统。在本项目中，我们验证了以下关于每个研究的结果。通过基本的数值仿真，验证了两自由度悬浮系统的可能性。在此基础上，设计并制造了第一台具有两个永磁体和执行器的两自由度悬浮系统样机。然而，对该系统的实验测试失败了。由于这一结果估计是由磁体吸引力的误差引起的，所以用有限元方法分析了磁体的吸引力。结果表明，磁铁的布置对力的大小有影响，由于力随物体位置的变化很敏感，很难使系统稳定。结果表明，由三个永磁体和执行器组成的系统可以很容易地通过反馈控制实现稳定。制作并验证了第二个原型系统。2自由度悬浮成功。在微悬浮研究中，考察了悬浮物较小时的稳定性。结果表明，对执行器的响应速度要求很高，如果控制器是数字控制器，则需要输出滤波。在此基础上，制作了一台采用压电作动器的悬浮系统样机。实验检测表明，直径为2 mm的铁球是可以悬浮的。

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.