微型肠道机器人扩张机构与能量接收线圈的设计与实验

Design and Experiment of Expanding Mechanism and Power Receiving Coil for Micro Intestinal Robot

研究并设计了一种新型扩张方式的能在肠道中运动和驻留的微型肠道机器人.该肠道机器人的扩张机构采用阿基米德螺线腿的方式进行扩张,扩张直径可达32 mm,变径比达到2.13.设计减速比为489的减速器,保证较大的输出转矩.对扩张机构的扩张臂进行力学分析,并通过实验测试了扩张机构的扩张力.进而,对能量接收线圈进行建模分析.结果表明:扩张机构扩张力的实验测试值与理论分析的整体趋势基本一致,最小扩张力为1.5 N,满足肠道扩张力的需求;优化线圈磁芯厚度、绕组层数以及绞线规格可以提高无线供能系统性能;当发射线圈驱动电流为1.4 A时,该接收线圈相应的传输功率为812 mW,能量传输效率为8.3%,能满足肠道机器人的功率要求.

A new type expanding mechanism for micro intestinal robot is designed to move and anchor in the intestinal tract. The mechanism is expanded by Archimedes spiral legs whose maximum expanding diameter reaches to 32 mm, and the variable diameter ratio is 2.13. The reduction ratio of the reducer is up to 489 to ensure large output torque. The dynamic characteristics of the expanding arm are analyzed, and the expanding force is tested through experiments. Then, the power receiving coil is modeled and analyzed. The results show that the overall trends of the experimental test value of the expanding force and the theoretical analysis are basically the same, and the minimum expanding force is 1.5 N, which satisfies the demand of intestinal expansion. The performance of the wireless power transmission can be improved by optimizing the thickness of the coil core, the winding layer and the specification of the strand wire. When the driving current of the transmitting coil is 1.4 A, the corresponding transmission power of the receiving coil is 812 mW and the energy transfer efficiency is 8.3%, which can satisfy the power requirements of the intestinal robot.