A Vision-Assisted Semi-Automatic Uterus Manipulation Approach Based on a Pose Estimating Trocar

Abstract

In this paper, we propose a new vision-assisted semi-automatic uterus manipulation approach based on a pose estimating trocar. In this approach, a trocar integrated with an inertial measurement unit and a range sensor is used to estimate the position of the tip of the laparoscopic tool with respected to the trocar's base frame and a robot which grasps a uterine manipulator is used to perform uterus manipulation. Position of the tip of the uterine manipulator with respected to the robot's base frame can be obtained by forward kinematics. The relationship between the trocar's and the robot's base frames are estimated with a vision based approach by considering the laparoscopic camera's extrinsic parameters. By this, the relative position between the tips of the uterine manipulator and the laparoscopic tool can thus be estimated. Automatic uterus manipulation which aims to maximize the distance between the fundus of the uterus and the laparoscopic tool tip can then be achieved. Experiments are conducted to verify the feasibility of the proposed approach.