Typically, this form is visual since vision is the highest bandwidth human sense. However, people who are blind or visually impaired must rely upon other senses to accomplish this perception. Haptic interface technology allows tangible realizations of data surfaces to be realized, providing an additional modality for data exploration and analysis. Unfortunately, the amount of information that can be perceived through touch is orders of magnitude less than that which can be perceived through vision. Consequently, multimodal techniques must be investigated that enhance the visualization environment and give the user control over the resolution of the visualization.
Current research focuses on multiresolution joint haptic-sonification techniques.
Nonlinear multiresolution decomposition algorithms are being developed that reduce the resolution of the data while preserving important perceptual cues, such as discontinuities or edges. Preserving such cues is particularly important in a haptic environment. Environment enhancements under development include object properties such as friction and texture as well as their sonic counterparts. Textures, for instance, can be modeled as stochastic processes that are modulated by the underlying data. Thus both haptic and sonic textures can be used in an analogous fashion to color in graphical visualization methods.