Modeling of torque transmission characteristics in surgical robot

The laparoscopy surgery has been developed well enough to use a surgical robot as the development of robot technology. As distinct from the traditional large invasive surgery, surgical robot conducts the operation through small invasive hole using instrument which performs surgery instead of surgeon hand. And surgeon just drives the robot using master system located far from patient. But the surgical instrument has a few obligations because it has to be inserted into the human body. It should be small size under 10 mm diameter and it is impossible to attach any electric sensors. To do proper control of instrument without sensor, especially to do force control, this paper analyzes the cable-pulley structure in the surgical robot instrument system and studies the method to estimate the grasping force by modeling the torque transmission between driving motor and instrument tip.