基于视觉的微机器人结肠镜运动导航

设计出一种用形状记忆合金驱动的头部转动机构和一种基于视觉的控制算法,用其进行了微机器人结肠镜在肠道内的自主导航研究.建立了转动机构模型,推导出记忆合金弹簧位移和偏转角度之间的关系.针对人体腔道内图像特点,使用腐蚀生长法找到腔道中心,反推出头舱的偏转角度和记忆合金弹簧位移.基于Preisach模型,提出了记忆合金驱动的前馈控制算法,进行了数字仿真和猪大肠内离体试验.结果表明,控制算法偏转误差小于2.6°,具有良好的实时性.该系统灵活可靠、控制方便,为主动式无创诊疗内窥镜的临床应用奠定了基础.

Active micro robot colonoscopy's navigation based on vision

A deflection structure of head cabin was designed and a corresponding control algorithm based on vision was presented to study the navigation of micro robot for colonoscopy in intestines.The deflection structure was driven by shape memory alloy(SMA).A deflection model was created to find the relation between the displacement of SMA spring and the deflection angle.The corrosion-growth algorithm was used to find the center of colonoscopy according to the feature of colonoscopy's images.The displacement of SMA and the deflection angle were calculated with the center point.The feed forward control algorithm based on Preisach model was presented to control the displacement of SMA actuator.Numerical simulation and in-vitro experiments in pig's colon were made.It was demonstrated that the deflection angle error in control algorithm was less than 2.6 degrees and had a good real-time feature.This system was flexible and reliable and easy to control,which has laid the foundation of autonomous non-invasive micro robot colonoscopy's clinical application.