A passive haptic interface was developed as a surgical aid tool for dental implant surgery. The placement of a dental implant is critical since positioning mistakes can lead to permanent damage in the nerves controlling the lips, long lasting numbness and failure of the implant and the crown on it. Haptic feedback to the surgeon in real time can decrease the dependence on the surgeon’s skills and experience for accurate implant positioning and increase the overall safety of the procedure.
The device is a lightweight mechanism with weight compensation. Rotary magnetorheological (MR)-brakes were custom designed for this application using the serpentine flux path concept. The resulting MR-brakes are 33% smaller in diameter than the only commercially available such brake yet produce 2.7 times more torque at 10.9 Nm. Another contribution of this research was a ferro-fluidic sealing technique, which decreased the off-state torque. Usability experiments were conducted to drill holes with haptic feedback. The maximum average positioning error was in 1-2mm range.
Publications
- “Passive Haptic Interface with MR-Brakes for Dental Implant Surgery,” Presence, MIT Press, vol. 20, No. 3, pp. 207-222, June 2011.
- “Optimum Design of 6R Passive Haptic Robotic Arm for Implant Surgery,” Proceedings of EuroHaptics 2010, Amsterdam, Holland, July 2010.