A Versatile Mechatronic Tool for Minimally Invasive Surgery

This paper describes a novel handheld mechatronic tool for minimally invasive surgery (MIS) able to assist the surgeon in several surgical acts and enhancing his (or her) dexterity and sensitivity. The main feature of this tool is the limitation of the risk of damage of the biological tissues in a plurality of procedures of manipulation (dissection, blunt dissection, pulling, stretching and stripping), of suture and cutting, in which the actuators included inside the tool assist the surgeon in performing these surgical acts. For this purpose, the mechatronic tool is equipped with an embedded microcontroller and sensors measuring the operating forces, which enable the closed loop force and torque control of the tool- tissue interaction. Through the consciousness and the direct control of the interaction forces, the surgeon can manipulate tissues selectively by the application of the operating forces on the basis of the surgical needs and of the tissue consistence. In particular, this paper discusses the design steps performed via a virtual prototyping approach implemented in a MATLAB/Simulinktrade environment and composed of kinematic, dynamical modeling and control system synthesis. The advantages in terms of simplification of the surgical act, resulting from the properties of servo-assistance of the tool, have been shown by the use of a preliminary version of the tool prototype in a simulation, performed by a pelvi trainer, that has involved complex tasks as suturing and knot tying.