Development of a Surgical-Forceps Driver with an Embedded High-precision Tiny Force Sensor Module

Abstract

We propose the forceps driver that can be applied to the tele-operated microsurgical robot platforms as an end-effector. In developing the device, it is aimed to implement the compact-sizable and lightweight forceps driver having high-precision gripping-force control capability. To achieve this aim, we mainly consider about two key components of the device: the actuator to drive the surgical-forceps and the sensor to measure the gripping-force. As the suitable actuator, the wire-type SMA (shape memory alloy) actuator is applied to the driver due to its operational merits such as high energy density and mechanical simplicity in configuring actuator system. And, in the case of the force sensor, a high-precision tiny BSFS (barometer-based soft force sensor) module exhibiting high sensitivity and linearity is fabricated and embedded into the driver. The forceps driver consisting of the SMA actuator, the BSFS module, and a simple driving mechanism is conceptually designed and then prototyped to experimentally carry out driving characterization and performance evaluation. In the experiments, the self-tuning fuzzy PID controller is designed and used for high-precision force control. The experimental result on the gripping-force controllability demonstrates that the minimum controllable gripping-force of the proposed forceps drive is about 0.07 N.