Introduction

The project consists of the Proof of Concept of a surgical instrument, a needle-carrying clasps used for minimally invasive robot-assisted surgery, which have been given the ability to reorient the needle by rolling it into the instrument’s working space.

Technical features

The invention consists of a novel laparoscopic instrument with a spherical wrist capable of grasping and rolling, in the working space of the instrument itself, an object such as a suture needle. Taking inspiration from the most common movements performed by surgeons during open surgery, two movements are of interest to take a step forward in manipulation capabilities in minimally invasive robotic surgery (MIRS): “rolling between the fingers” (RF) and “rolling for reorientation” (RR). The design of the instrument was performed considering the following requirements: (i) the instrument must fit into an 8.5 mm trocar; (ii) the size of the two fingers of the forceps must be the same as the size of the fingers of the standard needle holder forceps of the da Vinci robot whose efficiency has been widely demonstrated; (iii) the rotational movement that can be imparted to the most commonly used needles in laparoscopic procedures must be maximized by ensuring a rotation greater than ±90°.

Possible Applications

• PACMAN is an appropriate compromise between the use of classical laparoscopic instruments and the laparoscopic surgical technique;
• It is capable of imparting rolling motions on an object of circular cross section;
• The effectiveness of the proposed design has been demonstrated and validated in the laboratory.

Advantages

• Evaluation of measures of dexterity and manipulability of the robotic mechanism;
• Statistical analysis of time taken to complete tasks;
• Decrease in both completion time and second arm use.