Game Development Reference
Tactile interfaces/Actuation technologies
Figure 10.4 Tactile interfaces and actuation technologies
interfaces, is that of piezoelectric actuators. This is due to the significant integration
rate. It is also used in teleoperation applications when it involves integrating micro-
actuators on a glove. It represents more than 20% of the cases.
The technology of AMF has been exclusively employed by using AMF springs
and wires. The difficulty of controlling the AMF as well as their limited bandwidths
remains the major problems of these actuators. Mechanical solutions to amplify the
movement are proposed. It represents approx. 15% of the cases.
Even if technological solutions like the: MEMS, ER fluids or Polymers stir the inter-
est of a few, their use in tactile interfaces remains very little. Each of these technologies
represents approx. 5% of cases. Please note that none of the interfaces presented in
this chapter perform the fusion of all the physical parameters naturally present on a
real surface: temperature, vibration, pressure and others.
The studies based on the electrophysiologies of an animal and the studies by microneu-
rography of man, that help to record the response of the unit fibres to an electric or
sensory stimulation, have made it possible to determine the functional specificities of
the various types of cutaneous receptors in a better way. There is a distinction drawn
between cutaneous mechanoreceptors, thermoreceptors and nociceptors. In spite of
these studies, we still cannot interpret a large number of sensations related to touch.
This is without doubt related to the fact that the sense of touch is different from all
the other senses, in view of the fact that it cannot be isolated like vision and that
it intervenes in our interaction with the outside world in an almost permanent man-
ner. Many tactile interfaces have been manufactured to date in order to satisfy the
physiological specificities of the human tactile device. These specifications are even
more complex to verify as they include cost, portability, size, spatial and temporal