【摘要】 提出了一种形状记忆合金驱动的用于微创介入手术的主动导管,外径为1.25 mm。为了获得预期的弯曲角度而不过多的增加外径,主动导管采用多个弯曲单元串联的结构。考虑到形状记忆合金驱动器的输出力决定了导管轴线的挠度曲线的具体形式,在大挠度理论的基础上,利用曲率的精确表达形式建立了挠度曲线的微分方程,通过积分变换推导得出导管前端在预期姿态下各个形状记忆合金驱动器的输出力和长度,给出了精确的关节中心位置坐标,并将导管轴线的挠度曲线方程表达成便于计算的形式。本文为主动导管在人体血管中的准确定位提供了有利参考,并在一定程度上完善了该类问题的设计理论。更多还原

【Abstract】 A kind of active catheter used for minimally invasive surgery and actuated by shape memory alloy(SMA) was developed in this paper.The outer diameter of the catheter is 1.25 mm.The catheter was designed to consist of several bending units for achieving a large bending angle,but at the same time not increasing the outer diameter too much.It was considered that the deflection curve of axis of the catheter is determined by the output force of the SMA actuators.Based on large deflection theory,the deflection curve equation of the axis of the catheter was set up using precise form of the curvature.Through integral transform,the length and output force of each SMA actuator under the anticipative attitude of the tip of the active catheter were obtained,and the accurate coordinate of the center of the joint was givein.This study has provided great convenience to get control of the catheter,and has improved,to a certain extent,the design philosophy of problems such as active catheter.更多还原