Fiber-optic intubation simulator with force feedback

The existing simulators for fiber-optic intubation procedure provide haptic feedback to the user when there is contact with the vocal-cord section, but they do not capture the grazing effect of the endoscope along the inner walls of the airway. The grazing on the inner walls of the airway, if not well controlled, could lead to unnecessary trauma for the patient. Hence, there is a need to provide this force feedback in a fiber-optic intubation simulator. We have built a force feedback device that incorporates both the force feedback when contact is made with the vocal-cord section as well as grazing of the endoscope along the inner walls of the airway. We use a PD controller to obtain force feedback at the vocal-cord section and a variable magnetic field to replicate the frictional force feedback caused by the grazing of the endoscope along the inner walls of the airway. The movements of the endoscope are captured using rotary encoders (which read the insertion and the tip bend) and a magnetometer (which reads the twist angle of the endoscope along the long axis). We performed tests based on the intensity of contact of the endoscope against the vocal-cords and the inner walls of the airway. Changes in the intensity of grazing at the inner walls of the airway were observed by actively varying the coil current in the magnet. The simulator will help to train all aspects of fiber-optic intubation which involves contact with the vocal-cords as well as grazing the surface of the airway.