Development of Haptic Interface for Neurosurgical Simulators with Micro Scissors Module for Displaying the Cutting Force

Introduction of surgical simulators, which enable repeated learning of new surgical techniques, is advancing and they are desired in the field of neurosurgery. This study aims to make a two-fold contribution. First is the development of a haptic interface, which can be used while changing the operative tools necessary for training the cerebral fissure opening technique while using both the hands. Second is to develop a module for the haptic interface, which can display the cutting force when using micro scissors. To realize the operation with both the hands, the haptic interfaces for the right and left hands are designed so that they do not interfere. In addition, surgical tools, such as retractors, micro dissectors, and micro scissors, can be exchanged. In the cutting experiment carried out prior to the development of the haptic interface, it was clarified that the force when the dura mater was cut using micro scissors was 0.5 N. For comparison, the cutting forces required to cut two and three sheets of paper were measured to be 0.4 N and 0.6 N, respectively. The developed micro scissors module was designed using one motor and planetary gear mechanism. The gear mechanism is designed such that the right and left handles rotate in reverse directions around the rotation axis of the micro scissors using only one motor. This mechanism enables the micro scissors to cut the virtual tissues in the middle of the blade. The developed module could display a force of 0.4 N.