ABSTRACT
This chapter describes the use of AR within the haptic (active touch) sense for medical applications. Haptic augmentation in microsurgery is particularly desirable because surgeons routinely operate with little tactile input, relying instead on visual feedback obtained through a surgical microscope. The field of engineering haptics has expanded significantly in the past decade, yielding new technology for tactile and kinesthetic stimulation that simulates interactions with surfaces and materials. This technology not only has broad application, but also enhances the understanding of the underlying processes of human touch. After reviewing contributions by other researchers, the authors draw from their own research on a novel hand-held (ungrounded) system for augmenting tool-tissue force perception: the Hand-Held Force Magnifier (HHFM). Psychophysical measurements from users of the device validate a proposed human-in-the-loop control framework. Results show that in situ force feedback provided by the HHFM (i.e., augmenting the perception of force at the tip of a tool) can enable users to detect and differentiate small forces as well as they normally would for real forces of larger magnitude. Magnification also reduces the level and variability of contact force and reduces the power in spectral bands associated with tremor.
