螺旋布设光纤光栅的软体操作器形状传感方法

Shape Sensing Method of Soft Manipulator Based on Fiber Grating with Spiral Layout

摘要:

为实现微创手术软体操作器弯曲伸缩运动时的形状测量,提出一种螺旋布设光纤光栅形状传感方法。不同于传统的直线形布设方法,螺旋形布设方法可以防止软体操作器弯曲伸缩运动时,光纤光栅的折断、脱胶现象发生。理论分析了螺旋布设光纤光栅的传感原理及弯曲变形的重构算法；制备了光纤光栅沿螺旋形布设在软体操作器表面的试样；搭建了软体操作器弯曲变形的实验系统；实验分析了软体操作器在不同弯曲状态下,螺旋布设光纤光栅中心波长漂移量与弯曲角度间的变化规律,并重构出软体操作器的变形形状。实验结果表明:螺旋布设光纤光栅在软体操作器中不同位置的灵敏度最大为7.1pm/(°),软体操作器弯曲角度实际测量值与理论重构值间的最大误差不足4.29%。螺旋形光纤传感方法可用于软体操作器形状传感与重构。

Abstract:

In order to measure the shape of a minimally invasive surgical soft manipulator when it is flexing and stretching, a shape sensing method based on spirally arranged fiber grating is proposed. Unlike the traditional linear layout method, the spiral layout method can prevent the fiber grating from breaking and degumming when the soft manipulator flexes. The sensing principal of spirally arranged fiber grating and the reconstruction algorithm of bending deformation are analyzed theoretically. The sample of fiber grating placed on the surface of the soft manipulator along the spiral is prepared, and the experimental system for bending deformation of the soft manipulator is established. The variation of the center wavelength drift and bending angle of spirally arranged fiber grating under different bending conditions is analyzed experimentally, and the deformation shape of the soft manipulator is reconstructed. The experimental results show that the maximum sensitivity of the spirally arranged fiber grating in different positions of the soft manipulator is 7.1pm/(°), and the maximum error between the actual measured value of the bending angle of the soft manipulator and the theoretical reconstruction value is less than 4.29. The helical optical fiber sensing method can be used for the shape sensing and reconstruction of soft manipulators.