Force Sensing and Feedback System Based on Novel Triaxial Force Capacitive Sensor for Minimally Invasive Surgical Robot

Abstract

Minimally invasive surgery has attracted great attention due to small trauma, light pain, and quick recovery. Currently, most minimally invasive surgical robots lack the ability to force sense, resulting in high risks. Herein, a novel minimally invasive surgical force sensing and feedback system for minimally invasive surgical robot is proposed based on a flexible triaxial force capacitive sensor array. The capacitive force sensors utilize a microstructure electrode and orthogonal triangular pyramid microstructure to tackle the trade‐off between high sensitivity and wide‐detection range, showing 0–3 N detection range for normal force and high sensitivity of 69.19% N−1. Furthermore, the triaxial capacitive force sensors are integrated into the end‐effector of the minimally invasive surgical robot to form the minimally invasive surgical force sensing system. The system can show real‐time position of gripping or touching action, and the magnitude of triaxial force on the display surface. Importantly, the sensing force can further control the movement of the clamp, thus forming a novel force sensing and feedback system. The force sensing and feedback system of this minimally invasive surgical robot lays the foundation for its application in minimally invasive surgery andis expected to improve the safety and success of robotic‐assisted minimally invasive surgery.

A Novel Flexible Centralized Force Sensor Based on Tri‐Axis Force Refactoring Method for Arbitrary Force Components Measurement

“…[24][25][26][27][28][29][30] Zhang et al have reported a capacitive tri-axis force sensor with microstructures for invasive surgical applications. [31] And the tri-axis force sensor reported by Won et al can even measure temperature and bending angle. [32] Besides, Chen et al [33] have reported another combined structure using three piezoresistive sensing elements, which has similar sensing principle to the four elements' sensor using differential signals, and the capacitive sensor based on this threeelements structure has also been reported by Gu et al [34] Except for this commonly used multielements distributed structure, other structures for tri-axis force sensing have also been reported, [35][36][37][38] and some of them can even detect the force moment.…”