Magnetic Levitation Improves Tactile Feedback

Most other haptic interfaces - which give tactile feedback - rely on motors and mechanical linkages to provide some sense of touch or force feedback, but a device developed by Ralph Hollis, research professor in Carnegie MellonÃ's Robotics Institute, uses magnetic levitation and a single moving part to give users a highly realistic experience. Users can perceive textures, feel hard contacts and notice even slight changes in position while using an interface that responds rapidly to movements.

While the system is still huge - and far to bulky for touch-screen displays, as usually happens with these things - it will get smaller and cheaper over time.

"We believe this device provides the most realistic sense of touch of any haptic interface in the world today," said Hollis, whose research group built a working version of the device in 1997. With the help of a $300,000 National Science Foundation grant, however, he and his colleagues have improved its performance, enhanced its ergonomics and lowered its cost. The grant also enabled them to build 10 copies, six of which are being distributed to haptic researchers across the U.S. and Canada.

"We have gone from the prototype to a much more advanced system that other researchers can use," Hollis said. Putting the instrument in the hands of other researchers is critical in a young, developing field such as haptic technology, he emphasized. Though haptic interfaces have uses in engineering design, entertainment, assembly, remote operation of robots, and in medical and dental training, their full potential has yet to be explored. ThatÃ's particularly the case for magnetic levitation haptic interfaces because so few have been available for use by researchers, he added.

"This is an affordable device thatÃ's also practical," said Hollis, who has started a spinoff company to build additional devices. "Now other people can have this technology, and this represents technology transfer in the very real sense."

"The field of haptic research and development is expanding rapidly," said Rob Conway, project manager in Carnegie MellonÃ's Center for Technology Transfer. "Carnegie MellonÃ's research opens new possibilities by joining the world of haptic feedback with a comfortable magnetic levitation interface. The magnetic levitation decouples the interface device from the mechanical world, eliminating friction, backlash, jump, sticking and other interfering effects, so that the user feels only the artificial environment in complete accuracy down to the micro scale."

Posted to the site on 4th March 2008