Abstract
One of authors proposed a new method named overcoat method that is a system for sensing the force loaded on the tip of the surgical instrument. The overcoat method has two types of construction ways, trocar type and basic type. At first, the trocar type was tried, and the abilities and the characteristics of the trocar type were reported. This paper deals with the basic type of the sensor structure with the theoretical way of canceling the acceleration and gravity forces. It pointed out that main error on the force measuring is coursed by inaccurate motion of slave robot, and force measuring error of basic type is smaller than trocar type one.
