Haptic
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Haptic means pertaining to the technology of touch. It is an emerging technology that promises to have wide reaching implications.
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History
One of the earliest forms of haptic devices is used in large modern aircraft that use servo systems to operate control systems. Such systems tend to be "one-way" in that forces applied aerodynamically to the control surfaces are not perceived at the controls, with the missing normal forces simulated with springs and weights. In earlier lighter aircraft without servo systems, as the aircraft approaches a stall the aerodynamic buffeting is felt in the pilot's controls, a useful warning to the pilot of a dangerous flight condition. This control shake is not felt when servo control systems are used. To replace this missing cue the angle of attack is measured and when it approaches the critical stall point a "stick shaker" (an unbalanced rotating mass) is engaged, simulating the effects of a simpler control system. This is an example of haptic feedback.
Teleoperators and simulators
Teleoperators are remote controlled robotic tools, and when contact forces are reproduced to the operator, it is called "haptic teleoperation". The first electrically actuated teleoperators were built in the 1950's at the Argonne National Lab, USA, by Dr. Raymond C. Goertz, to remotely handle radioactive substances. Since then, the use of force feedback has become more widespread in all kinds of teleoperators such as underwater exploration devices controlled from a remote location.
When such devices are simulated using a computer (as they are in operator training devices) it is useful to provide the force feedback that would be felt in actual operations. Since the objects being manipulated do not exist in a physical sense, the forces are generated using haptic (force generating) operator controls. Data representing touch sensations may be saved or played back using such haptic technologies.
Haptic simulators are currently used in surgery training and flight simulators for pilot training (2004).
Games
Some low-end haptic devices are already common. Some joysticks and game controllers provide haptic feedback. The simplest form are "rumble packs", which are simply attachments which vibrate upon command from the software. Some joysticks also support force feedback. Simulated automobile steering wheels are now available which provide the road "feel" for race car simulations.
Haptics in virtual reality
Haptics is gaining widespread acceptance as a key part of Virtual Reality systems, adding the sense of touch to the previously visual only solutions such as 'The Wedge' (http://wedge.anu.edu.au/) and more recently in laptop based VR solutions such as the '3D-Mobile Immersive Workstation' (http://www.sensegraphics.com). Most of these solutions use so called stylus based haptic rendering, where the user interfaces to the virtual world via a tool or stylus, giving a form of interaction that is computationally realistic on today's hardware.
Research
Some research has been done into simulating the different kinds of tactition by means of high-speed vibrations or other stimuli. One device of this type uses a pad array of pins, where the pins vibrate to simulate a surface being touched. While this does not have a realistic feel, it does provide useful feedback, allowing discrimination between various shapes, textures, and resiliencies.
Medicine
Various 'Haptic interfaces for medical simulation' (http://www.xitact.com) may prove especially useful for training of minimally invasive procedures (laproscopy/interventional radiology) and remote surgery using teleoperators. In the future expert surgeons may work from a central workstation, performing operations in various locations, with machine setup and patient preparation performed by local nursing staff. Rather than traveling to an operating room the surgeon instead become a telepresence. A particular advantage of this type of work is that the surgeon can perform many more operations of a similar type, and with less fatigue. It is well documented that a surgeon who performs more procedures of a given kind will have statistically better outcomes for his patients.
Literature
The use of haptic devices in entertainment appeared in the 1932 futurist fiction book Brave New World by Aldous Huxley. The author described a future entertainment theater where the arm rests of the seats had positions for the hands to rest that gave haptic stimulation. Rather than "the movies" these theaters and shows were called "the feelies". The programs exhibited were of an erotic nature.
Remote sexual relations
One envisioned use of haptics is for "teledildonics". This used to be a fanciful notion, not really having any bearing on reality, but recent developments such as the 'cyber glove' (http://www.mindflux.com.au/products/vti/cyberglove.html) indicate that it might not be so strange a notion. Some sex toys are now available which can be computer controlled; normally this comes in the form of an online movie or website which sends commands to the toy at scripted moments. It is not uncommon that the pornography industry is among the early adopters of a new technology; for example, the multiple-viewpoint feature of DVDs was first widely used in pornography, and the internet is notorious for having been so swiftly exploited by those who work in the porn business.
External links
- International Society for Haptics (http://www.isfh.org)
- Haptics: The Technology of Simulating Human Touch (informit.com) (http://www.informit.com/articles/article.asp?p=361412)
- MIT Touch Lab (Laboratory for Human and Machine Haptics) — Multiple Section Article (http://touchlab.mit.edu/index.html)
- [1] (http://www.wired.com/news/technology/0,1282,67513,00.html?tw=wn_story_top5) Wired article on haptic chicken, remote hug suits, etc
- Haptics-L, the Electronic Mailing List for the International Haptics Community (http://www.roblesdelatorre.com/gabriel/hapticsl/)it:Interfaccia aptica