Snail surgeon: a new robotic system for minimally invasive surgery

The paper discusses the architecture and the workspace of a special modular surgical robot designed for minimally invasive surgery (keyhole surgery). The surgeon can be asked to operate on an organ not directly reachable through any keyhole opened on the patient abdomen, e.g. due to the presence of other organs surrounding it. In this case, an alternative to complex and dangerous displacement operations of the surrounding organs inside the patient is the use of a highly dexterous robotic arm able to reach the operating region by moving around the organs. The paper proposes a mini robot composed of modules with different mobility connected in series through mechanical/power/control interfaces. The workspace and performances of the robot can be adapted to the particular surgical operation to be carried out by changing the composition of the chain (type and position of the modules). Data stored in a database allow the easy determination of the workspace and provide information about the velocity ellipsoids and the presence of singularities. With reference to the results of the preoperative exams and by means of the information stored in the database, the best robot architecture, for the surgical operation to be carried out, can be selected.