Design of a Novel Flexible Robotic Laparoscope Using a Two DegreesofFreedom CableDriven Continuum Mechanism With Major Arc Notches

Abstract

This article presents the design, development, and motion control of a novel flexible robotic laparoscope (FRL). The main structure of the FRL includes a two degreesoffreedom (DOFs) continuum mechanism driven by two pairs of cablepulleydriven systems, which are actuated by four miniature linear actuators. A constantcurvature model is employed on the kinematics modeling and analysis of the continuum mechanism with designed major arc notches. The bending control strategy of the continuum mechanism is proposed and realized based on its kinematics model and a feedforward compensation method considering its nonlinearity motion calibration with a suitable initial tension of the driven cables. Besides, the continuum mechanism is made of elastic nylon material through 3D printing technology. An experimental prototype is developed to test the effectiveness and feasibility of the FRL. The experimental results indicate that the FRL has good positioning accuracy and motion performance with potential applications in robotassisted laparoscopic surgery.