This article at NewsScientists talks about a new haptics device “levitated by magnets”.

[youtube]http://www.youtube.com/watch?v=isu7r3Ywqp0&eurl=http://technology.newscientist.com/article/dn13410-maglev-joystick-gives-better-feedback.html[/youtube]

Ralph Hollis and colleagues at Carnegie Mellon University, Pittsburgh, US, developed a haptic device with just one moving part. (…)

A bowl with electromagnets concealed below its base contains a levitating bar that is grasped by a user and can be moved in any direction. The magnets exert forces on the bar to simulate the resistance of a weight, or a surface’s resistance or friction. LEDs on the bar’s underside feed back its position to light sensors in the bowl.

This approach has “huge potential”, says Anthony Steed, a haptics researcher at University College London, UK. “This system gets rid of the mechanical linkages that are a major constraint on most haptic devices.”

The maglev interface can exert enough force to make objects feel reassuringly solid, says Hollis, resisting as much as 40 newtons of force before it shifts even a millimetre.

That’s enough to feel the same as a hard surface and better than most existing interfaces, he says. “Current devices feel very mushy, so it’s hard to simulate a hard surface.”

The device can track movements of the bar as small as two microns, a fiftieth the width of a human hair. “That’s important for feeling very subtle effects of friction and texture,” says Hollis.

And it can exert and respond to all six degrees of freedom of movement – moving along or rotating about each of the three dimensions of space.”It offers things that other devices just can’t do – the high forces, low friction, low inertia, and six degrees of freedom.”

After working on a series of prototypes since 1997, Hollis has started a company called Butterfly Haptics to market the technology.