Towards a steerable multi-module soft robotic endoscope for NOTES applications

摘要

This project comprised the design and fabrication of a multi-module endoscope for Natural Orifice Transluminal Endoscopic Surgery (NOTES) based on MR-compatible soft robotic modules. The modules are silicone tubes containing pneumatic chambers bend the module when pressurized. Based on literature, analytical calculations and simulations, the theory behind the bending of the individual modules was examined and their design was altered to improve the repeatability and linearity of the actuation. While the maximum bending angle of the modules was decreased, repeatability in fabrication was achieved. The differences in bending angle between the modules were decreased and orientation of the modules was no longer dependent on the actuation order. This opened the door to using a linear model of the endoscope for control instead of depending on the characterization of the whole range of the actuator. Three modules were stacked to form a prototype of the endoscope. Steering of the endoscope was achieved by developing software and electronic hardware that control pneumatic pressure regulators and solenoid valves. A novel method using micro-pneumatic valves was tested and implemented in order to control the endoscope with minimal pneumatic hardware such as pressure regulators and tubing. This improves the scalability of the system.