Enriquez, M., "A study of haptic icons", M.Sc. Thesis, Univ. of British Columbia, 2002.
The goal for this research is to study a new class of force feedback applications based on abstract messages we call haptic icons. With the introduction of active haptic displays, a single knob or joystick can be used to control several different, sometimes non-related, functions. The functions associated with these multi-function handles can no longer be identified from one another by position, shape or texture differences. Haptic icons are brief programmed forces applied to a user through a haptic interface conveying an object's or event's state, function or content in a manner similar to visual or auditory icons. This thesis begins with a presentation of several tools that were developed to aid this research. It then describes a series of psychophysical tests designed to obtain the basic perceptual limits for our haptic interface. Knowing these perceptual limits is a prerequisite for proper haptic icon design. We analyzed a set of synthetically constructed haptic icons using Multidimensional Scaling, in order to discover the underlying perceptual processes in identifying different haptic stimuli. Results show that a set of icons constructed by varying the frequency, magnitude and shape of 2-sec, time-invariant waveforms map to two perceptual axes, which differ depending on the signals' frequency range, and suggest that expressive capability is maximized in one frequency subspace. I finish by proposing future work to be done on this area.