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

One issue of robotic microsurgery is that compared 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 microsurgery. 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.