柔性手术机器人牵引钢丝绳与弹簧管的关系分析

Study on the Relationship Between Wire Rope and Spring Tube Drawn by Flexible Surgical Robot

内窥镜进入被检体后无法通过传回的画面准确判断内窥镜整体形态,为更精准的控制弯曲部的蛇骨弯曲,需要分析插入导管及其内藏物的相互关系。分析内藏物中弹簧管与钢丝绳的部分,提出了插入导管中牵引钢丝绳和弹簧管在不受力时位置关系的理论模型,基于Ramberg-Osgood模型推出了钢丝绳受拉后钢丝绳弹性变形量,结合实验数据利用最小二乘法拟合出了钢丝绳长度变化量与拉力、盘曲半径和盘曲角度之间的关系公式。经实验验证在钢丝绳不受力时误差在10%以内,在钢丝绳受拉后理论公式与实验数据的误差在16%以下的数据点占总数据点的90%。

After the endoscope enters the subject,it cannot accurately judge the overall shape of the endoscope through the returned picture.In order to more accurately control the curvature of the snake bone,it is necessary to analyze the interrelation between the insertion tube and its artifacts.This paper analyzes the spring and the steel wire rope in the inner objects and proposes a theoretical model of the relative position between the traction steel wire rope and the spring tube when inserted into the pipe without force.Based on the Ramberg-Osgood model,the elastic deformation of the steel wire rope after tension is derived.Based on the experimental data,the relation formulae between the length variation of the wire rope and the tension,the bending radius and the bending angle are fitted with the least square method.It is proved that the error is less than 10%when the wire rope is not stressed,and for 90%of the total data points,the error between the theoretical formula and the experimental data is less than 16%after the wire rope is strained accounts.