Introduction (excerpt): The instrumentation described in the present paper provides for accurate control of all stimulus variables involved in vibrotactile stimulation of the tongue. It produces a wide range of frequencies and intensities and at the same time provides a unique and precise way in which to position the tongue for testing.
Fucci, D., et al. (1990). Instrumentation for assessment of oral vibrotactile sensation and perception, International Journal of Orofacial Myology, 16 (1), 8-12.