Development of an integrated haptic system for simulating upper gastrointestinal endoscopy

Abstract Virtual reality together with haptics offers immersive and flexible platforms for training doctors in medical procedures. In this paper, we present mechanical design, control, integration, and user-studies of a virtual reality-based haptic simulator for Upper Gastrointestinal (GI) endoscopy. The design overcomes some of the limitations of the existing systems. First, there is an extra degree of freedom for simulating junctions controlled by sphincter muscles in addition to translational and rotational degrees of freedom along and about the axis of the endoscope-tube. Second, the force-feedback is continuous over a longer range in all three degrees of freedom. Third, multiple insertions and removals of the tube are made possible with a magnetically actuated snap-fit mechanism. A Dynamics-based feed-forward control algorithm is developed and characterized for fidelity and transparency. The system provides continuous force up to 11 N in the axial direction and continuous torque up to 255 mN.m about the axial direction. The haptic device is integrated with a physics-based Virtual Reality (VR) interface. Furthermore, an immersion study was conducted using the integrated system with a cohort of novice and experienced clinicians. The haptic response and virtual model were rated high and improvements were suggested for graphical visualization and physical arrangement.