An Inexpensive, Highly Portable Optical to Haptic Graphical Display

Current methods available to represent graphical information to individuals who are blind or visually impaired are too expensive and/or cumbersome to be of practical use. Therefore, there is a need for an affordable display device capable of rendering graphical information through stimulation of working sensory systems. To further facilitate individuals, the device must be portable, as to enable them to use it in many different settings, and highly affordable, as most individuals who are blind are also unemployed. In this paper a dynamic display haptic device is described that is both affordable (<$25 US) and portable (<1 kg). The device uses a photo-interrupter to detect contrasts in light reflectivity for an image and vibrating solenoid motors to provide tactile feedback. The device is worn like a glove, so the tactile feedback combines with the body's kinesthetic sense of position of the hand to convey a haptic image. Preliminary tests show that a single-finger model of the device has on average a 50% object identification accuracy, which is higher than the accuracy for raised-line drawings. The device can be expanded for use of multiple fingers, while still remaining affordable (<$50 US).