A Haptic Virtual Borescope for Visual Engine Inspection Training

A haptic virtual borescope is developed for the purpose of aircraft engine inspection training, similar in spirit to borescope trainers intended for use in gas turbine maintenance training schools. Such devices consist of engine section mockups for use with a real borescope. Our approach instead simulates engine sections in virtual reality, replacing the need for physical mockups. We model the engine casing as a "black box" where a simulated borescope tip is inserted (in practice a real borescope is used to provide tactile veridicality of the probe's braided sheath but the camera at its tip is not used). The probe's translational movement is mapped to the virtual camera's. The graphical engine representation can conceivably generalize to any engine section that can be modeled graphically. Since the interior chamber of the "black box" casing is empty, the critical component of our simulator is correct borescope tip navigation as well as force feedback response based on a mathematical model of collision detection of the tip in the computer generated environment. Haptic response is thought to be a key component of the simulator as it provides non-visual tactile awareness of the borescope tip within the engine under inspection and, more importantly, its contact with engine surfaces. Our contribution is two-fold. First, we design a novel motor-powered clamp that provides collision response to collision of the camera detected in virtual space. Second, we attempt to isolate the effect of the system's tactile response and provide empirical evaluation of its utility. In line with previous results, our empirical analysis reveals a trend toward a benefit in performance (speed), but suggests that the provision of haptic feedback, while preferred over a solely visual interface, may be perceived as extraneous in a visually-dominated discrimination task.