Design of a spine-inspired kinematic for the guidance of flexible instruments in minimally invasive surgery

One standard procedure in minimally invasive surgery (MIS) is the endoscopic submucosal dissection (ESD), where neoplastic mucosal tissue is being removed. To execute an ESD the surgeon needs to be well-trained and experienced to operate the flexible instruments precisely under visual monitoring. One of the main drawbacks is the unintuitive control of standard systems and the limited possibility for triangulation. Big motions on the endoscope´s handle are transmitted into small movements of the endoscope´s distal end inside the stomach and changing the field of view also changes the instrument´s orientation and vice versa. We chose the ESD as a starting point to advance to Natural Orifice Transluminal Endoscopic Surgery (NOTES) later on. To improve the ESD, we develop a telemanipulation system, mainly fabricated by selective laser sintering (SLS) of a biocompatible polymer. In this paper we present our spine-inspired kinematic driven via push rods and bowden cables that provides sufficient triangulation with a promising trade-off between flexibility to insert the systems into the patient and adequate stiffness to reliably manipulate the mucosal tissue. To connect the actuators, we use a magnetic coupling to separate sterile and non-sterile parts.