肠道微机器人柔性运动系统

Flexible locomotion system for gastrointestinal microrobots

提出一种适用于肠道微机器人的柔性运动系统来提高肠道机器人微创诊断的主动运动能力。柔性运动系统采用尺蠖型运动方式,由柔性运动机构和柔性驱动机构组成。柔性运动机构包括径向气囊软足和轴向伸缩推杆,并用万向节连接微机器人前后腔体从而提高运动柔性;柔性驱动机构利用尼龙线绳牵引波纹管泵驱动气囊软足和伸缩推杆激励微机器人伸缩。微机器人样机直径为12.2mm,长度为78mm,质量为14.8g,最大径向钳位外径为20.2mm,最大轴向行程为16.4mm。实验结果表明,柔性驱动机构可以为波纹管泵和伸缩推杆分别提供最大为0.67N和0.65N的驱动力;微机器人样机能够在不同倾斜角度的刚性有机玻璃管中运动,在水平和竖直管道中的平均运行速度为0.38mm/s和0.25mm/s;能通过最小曲率半径为49.3mm的塑料软管,在离体肠道中也能实现有效运动。本柔性运动系统为肠道微机器人提供了一种安全有效的自主运动方案。

A flexible locomotion system is proposed to improve the active locomotion ability of gastro intestinal microrobots in the minimally invasive diagnosis. The locomotion system simulating inch wormlike locomotion comprises a flexible locomotion mechanism and a drive mechanism. The flexible locomotion mechanism is mainly composed of radial balloon feet and an axial telescopic pushrod. In addition, a developed universal joint is used to join two cavities of the microrobot to improve its loco motion flexibility. The drive mechanism uses the nylon wires to actuate the bellows bump for the bal loon feet and stimulate the telescopic pushrod for the microrobot to realize the flexible drive. The de veloped microrobot prototype shows its diameter in 12.2 ram, length in 78 mm and the weight in 14.8 g, and realizes the maximum clamping diameter of 20.2 mm and the maximum axial stroke of 16 mm. The experiments show that the wire drive mechanism can provide the maximum force of 0. 67 N for the bellows bump and 0.65 N for the axial pushrod, respectively. The microrobot prototype can move in the rigid plexiglass tube with different angles, and the average speeds in the horizontal and verticaltubes are O. 38 mm/s and O. 25 mm/s, respectively. In addition, it can move in the curving plastic tube with a minimum curvature radius of 49.3 mm and present an effective locomotion in vitro intesti nal tract. It can be seen that the flexible locomotion system provides an effective and safe locomotion ease for gastrontestinal microrobots.