Human Performance and Workload Evaluation of Input Modalities for Telesurgery

Abstract

In the last decade, surgical robots have been used routinely to assist surgeons e.g. during minimally-invasive surgery. Surgical instruments (e.g. needle drivers, scissors) are not directly manipulated by the surgeon, but by robotic arms located at the operation table. The surgeon controls the robotic system from a separated console with input devices. In contrast to conventional laparoscopy, a high degree of dexterity can be achieved by using such telerobotic systems despite the physical constraints of minimally-invasive surgery (also labeled as “keyhole technology”). In the current study, we empirically evaluated three different input modalities for telesurgery in a simulation environment. A sample of 18 individuals performed a pursuit tracking task using a mechanically coupled 6 DoF input interface (sigma.7) with vs. without friction/ inertia compensation or a freely moveable, optically tracked input interface. Besides input modality, movement scaling (high vs. moderate vs. low movement scaling), and arm stabilization (with vs. without armrest) were varied systematically. Results revealed positive effects of reducing friction/ inertia on manipulative precision and subjective workload, with the best results for the optically tracked device with minimal inertia and no friction. Yet, moving the device freely without any movement stabilization proved to be physically more demanding compared to the mechanically coupled interfaces.