oa Discrimination thresholds of virtual curvature for hapticand visual sensory information and future applicationsin medical virtual training

The senses of vision and touch are vital modalities used in the discrimination of objects. Recent advances in human-computer interface technologies have produced various haptic force feedback devices for the industries of rehabilitation, information technology, entertainment, and more. In this research effort, an inexpensive stylus-type haptic device is used to determine thresholds of concave curvature discrimination in visual-haptic experiments. Discrimination thresholds are found for each sense independently as well as for combinations of these with and without the presence of conflicting information.

Results indicate that on average, the visual sense is about three times more sensitive than the haptic sense in discriminating curvature in virtual environments. It is also noticed that subjects seem to rely more heavily on the sense that contains the most informative cues rather than on any one particular sense, in agreement with the sensory integration model proposed by other researchers. The authors believe that the resulting thresholds may serve as relative comparisons between perceptual performance and this study may be further expanded to audio and texture senses supported by the Undergraduate Research Enhancement Program (UREP) of the Qatar National Research Fund. It is also noted that these preliminary studies will constitute a valuable asset to the medical virtual training research and development.