A Tele-Operated Microsurgical Forceps-Driver With a Variable Stiffness Haptic Feedback Master Device

We develop a surgical forceps-driver and a haptic feedback master device that could be applied to a tele-operated microsurgical robotic system for peripheral nerve surgery. Considering that the neurological damage could occur to the peripheral nerve when an excessive force is applied to the nerve tissue, we aim to implement the forceps-driver with precision gripping-force control and the master device capable of providing haptic feedback. For this aim, a high-precision tiny force sensor is fabricated and embedded into the forceps-driver for gripping-force measurement. And, we develop a novel master device handled by surgeon's thumb and forefinger. As a kind of a variable stiffness module, it functions to generate the forceps-drive operation command according to a surgeon's pinching motion and to display haptic feedback by varying the stiffness based on the gripping-force measured from the slave device. Thus, the surgeon can tele-operate the forceps-driver intuitively as well as feel the gripped-object by proprioceptive haptic feedback. In the performance evaluation experiments for the master-slave system, the gripping-force measurement capacity of the forceps-driver and the stiffness variation range of the master device are investigated as about 4 N with a resolution of 0.03 N and about 3.6 N/mm with a resolution of 0.025 N/mm, respectively.