Preliminary Study of Fingertip and Wrist Motion Based Haptic Controller for Robotically Assisted Micro and Supermicrosurgy

One issue of robotic microsurgery is that com- pared to manual surgery, the operation time tends to be longer due to high motion scaling. To address this issue, we developed a new controller that can provide the accuracy required for microsurgery without a high scaling factor by utilizing fingertip and wrist motions. Also, for the better outcome of surgery, the proposed controller has a force feedback function which is not available for the existing controllers for microsurgical robots. A challenge of designing such a controller is associated with the size requirement. For conventional microsurgery, surgeons perform surgical procedures while looking at the eyepieces of a surgical microscope and the same applies for robotic micro- surgery. The only space available to manipulate controllers is a narrow space between the patient/surgical bed and the surgeon. To satisfy this constraint, the proposed controller is integrated with a handrest and the controller’s DOFs are strategically allocated. In this work, as the first step of addressing the issue of prolonged operational time, we built a prototype controller and evaluated the accuracy and task space with simulations. The results indicated that by using the fingertip and wrist motions with a scaling factor of 3x, 0.5 mm diameter circles could be traced with a mean bidirectional precision of 0.0485 mm. Also, 10.0 mm diameter circles were traceable with the same scaling factor.