Construction of an integrated soft micro mobile robot for surgery support in the abdominal cavity

NOTES (Natural Orifice Translumenal Endoscopic Surgery), a recently developed form of minimally invasive surgery, has attracted attention as a new laparoscopic operation. However, manipulation of forceps throughout the surgery continues to be a burden to surgeons. Our previous research focused on designing a model that could carry forceps and a camera through the abdominal cavity. The robot moves on the abdominal wall upside down, operated with six wires which realize the relative motion of two suction cups attached or detached from the abdominal wall. The robot could move forward/backward, turn right/left motion and move up/down. However the robot body containing commercialized products and self-designed parts was too big for the use in real surgery. Therefore, we devised an integrated robot with built-in suction cups, air ducts and housings, all made of a rubber-like soft material, for the miniaturization. In this study, we designed and manufactured the integrated robot, and investigated the influence of the deformation due to the softness of the robot, by a three-dimensional motion analysis. Moreover, for a feasibility study, 4 movements: moving forward/backward and turning right/left by the prototyped robot were tested. Results showed that in manual operation, the deformation of the suction cup and the air joint does not affect the robot motion to a crucial extent, that is, the 4 movements of the integrated soft robot are possible to realize. This raised the possibility that this robot system could be used for NOTES support.