High-Dexterity Telemanipulation Robot for Minimally Invasive Surgery

Abstract

A robotic telemanipulation system for single-port laparoscopy (SPL) is presented, introducing several advantages over known systems. Principally, the system offers great flexibility at the surgical site as the instrument arms are segmented and articulate within the abdominal cavity. The instrument arms were thoroughly designed to ensure stability while maintaining a small cross-section, thus keeping patient trauma to a minimum. Apart from the arms’ solidity, the need for strong actuators is another factor that arises due to the requirement for high manipulation forces during surgery. As, at the same time, available space is extremely limited, extensive research was conducted for finding suitable actuators. Several types of actuators as well as positions within the system were taken into account, prototypes built and tested. Also, as the need arose for some concepts, mechanisms for transporting kinetic energy from the actuators to the joints were examined. Applying the results of this work, it was possible to build a telemanipulation system consisting of instrument arms, a support base, and a specifically designed user interface. A computer serves to calculate instrument trajectories and respective joint positions from the user input at the interface as well as to facilitate communication between the system’s components. The system exceeds previously defined goals concerning dexterity. Practical tests demonstrated the broad range of movement. At the same time, the extracorporeal components are considerably smaller than their counterparts in telemanipulators on the market, thus improving direct access to the patient during surgery. Furthermore, the complex kinematics of the instrument arms are controlled via an interface with simplified kinematics modelling the instrument’s degrees of freedom (DOF), resulting in intuitive and precise handling.