Force perception on medical instruments is critical for understanding the mechanism between surgical tools and tissues for feeding back quantized force information, which is essential for guidance and supervision in robotic autonomous surgery. Especially for continuous curvilinear capsulorhexis (CCC), it always lacks a force measuring method, providing a sensitive, accurate, and multi-dimensional measurement to track the intraoperative force. Furthermore, the decoupling matrix obtained from the calibration can decorrelate signals with acceptable accuracy, however, this calculating method is not a strong way for thoroughly decoupling under some sensitive measuring situations such as the CCC. In this paper, a three-dimensional force perception method on capsulorhexis forceps by installing Fiber Bragg Grating sensors (FBGs) on prongs and a signal decoupling method combined with FASTICA is first proposed to solve these problems. According to experimental results, the measuring range is up to 1 N (depending on the range of wavelength shifts of sensors) and the resolution on x, y, and z axial force is 0.5, 0.5, and 2 mN separately. To minimize the coupling effects among sensors on measuring multi-axial forces, by unitizing the particular parameter and scaling the corresponding vector in the mixing matrix and recovered signals from FastICA, the signals from sensors can be decorrelated and recovered with the errors on axial forces decreasing up to 50% least. The calibration and calculation can also be simplified with half the parameters involved in the calculation. Experiments on thin sheets and in vitro porcine eyes were performed, and it was found that the tearing forces were stable and the time sequence of tearing forceps was stationary or first-order difference stationary during roughly circular crack propagating.

翻译：医疗器械上的力感知对于理解手术工具与组织间的作用机制至关重要，可为机器人自主手术提供量化的力反馈信息，从而指导与监控手术过程。尤其在连续环形撕囊（CCC）手术中，目前缺乏能够实现灵敏、准确且多维测量的术中力追踪方法。此外，虽可通过标定获得的解耦矩阵以可接受的精度消除信号相关性，但在CCC等敏感测量场景中，该计算方法并非彻底解耦的强效手段。本文首次提出一种在撕囊镊钳齿上安装光纤布拉格光栅传感器（FBGs）的三维力感知方法，并结合FASTICA信号解耦技术解决上述问题。实验结果表明，测量范围高达1N（取决于传感器波长偏移范围），x、y、z轴向力分辨率分别为0.5mN、0.5mN和2mN。为最小化多轴力测量中传感器间的耦合效应，通过统一特定参数并缩放混合矩阵及FastICA恢复信号中的对应向量，可对传感器信号进行去相关与恢复，使轴向力测量误差降低至少50%。标定与计算过程亦可简化，所需参数减少一半。在薄片及离体猪眼上的实验表明，撕裂力保持稳定，且在近似圆形裂纹扩展过程中，撕拉力序列呈平稳或一阶差分平稳特征。