Mechanical Manipulator for Intuitive Control of Endoscopic Instruments With Seven Degrees of Freedom

Performing complex tasks in Minimally Invasive Surgery (MIS) is demanding due to a disturbed hand-eye co-ordination, the use of non-ergonomic instruments with limited degrees of freedom (DOFs) and a lack of force feedback. Robotic telemanipulatory systems enhance surgical dexterity by providing up to 7 DOFs. They allow the surgeon to operate in an ergonomically favorable position with more intuitive manipulation of the instruments. Commercially available robotic systems, however, are very bulky, expensive and do not provide any force feedback. The aim of our study was to develop a simple mechanical manipulator for MIS. When manipulating the handle of the device, the surgeon’s wrist and grasping movements are directly transmitted to the deflectable instrument tip in 7 DOFs. The manipulator consists of a parallelogram mechanism with steel wires. First phantom experience indicated that the system functions properly. The MIM provides some force feedback improving safety. A set of MIMs seems to be an economical and compact alternative for robotic systems.