Design Synthesis of a Robotic Uniaxial Torque Device for Orthopedic Haptic Simulation

Robotic devices are commonly used in surgical simulators to provide tactile, or haptic, feedback. They can provide customized feedback that can be rapidly modified with minimal hardware changes in comparison to non-robotic systems. This work describes the design, development, and evaluation of one such tool: a novel uniaxial torque haptic device for a surgical training simulator. The objective of the work was to design a single connection haptic device that could augment an existing six degree of freedom haptic device to mimic a Concorde Clear vacuum curette. Design and evaluations focused on the tool's ability to deliver adequate torque, imitate a surgical tool, and be integrated into the haptic device. Twenty-nine surgeons tested the tool in the simulator and evaluated it via a questionnaire. The device was found to deliver the 800 N·mm of torque necessary to mimic an orthopedic procedure. Surgeons found it accurately imitated surgical tool physical appearance and maneuverability, scoring them 3.9±1.0 and 3.3±1.2, respectively, on a 1-5 Likert scale. By virtue of the functionality necessary for testing and evaluation, the device could be connected to the haptic device for mechanical and electrical engagement. This device is a step forward in the field of augmentable haptic devices for surgical simulation. By changing the number of robotically-controlled degrees of freedom of a haptic device, existing devices can be tuned to meet the demands of a particular simulator, which has the potential to improve surgeon training standards.