Research on the development of micro-actuator for medical checkup of stomach and intestines

本研究的目的是研制一种用于胃肠道肿瘤检查的磁力驱动系统和微机械控制系统。在1年的时间里，设计并制造了极距170 mm、磁场10mT的磁力驱动系统样机和旋转系统。通过机械旋转系统，实现了对微电机前进方向的三维控制。为了提高鳍式微致动器的效率，微致动器的总长度从40 mm减少到20 mm，最大推进速度提高到150 mm/s。在接下来的2年里，我们致力于三维控制系统的开发。首先，为了提高微致动器直线推进的稳定性，设计了优化的结构尺寸。然后通过改变产生磁场的交流电的平均电平(偏置)和幅值来控制微电机的方向和速度。这些控制可以通过使用操纵杆(方向控制)或拨盘(速度控制)来选择。此外，为了降低大规模磁驱动系统的成本，还开发了另一种电磁铁直角交叉耦合的三维控制系统，并对其基本性能进行了验证；检查、诊断和给药系统的研发主要由国外合作研究人员负责，并对胶囊式内窥镜的应用进行了考察。

The purpose of the research was to develop a magnetically driving system and the control system for micro-machine to he used for checkup of tumor in stomach and intestines.In the 1^<st> year a prototype of magnetically driving system with the polar distance of 170 mm and magnetic field of 10 mT and the rotating system was designed and manufactured. Rotating the system mechanically, 3 dimensional control of advancing direction of micro-machine could he conducted. Improving the efficiency of micro-actuator with a fin, total length of the micro-actuator was reduced from 40 mm to 20 mm and the maximum advancing velocity was increased up to 150 mm/s.In the 2^<nd> year effort was focused on the development of 3 dimensional control system. First of allOptimum configuration and dimension was developed to improve the stability of straight advancement of micro-actuator. Then the direction and velocity of the micro-machine was found to he controlled by changing average level (bias) and amplitude of wave form of an alternating current for generating magnetic field, respectively. These controls can be selected either by using joystick (direction control) or by dial (velocity control). Moreover in order to reduce the cost of large-scale magnetically driving system, another type of 3 dimensional control system with crossing couples of electromagnets at right angles was developed and the basic performance was proved.Research and development of checkup, diagnosis and drug-delivery system was mainly, in charge of foreign cooperative researchers and also examined on utilization of a capsule-type endoscope.