Support for active hands

March 21, 2012

Sometimes great ideas are just sitting out there waiting to happen. For William Provancher, an assistant professor of mechanical engineering at the University of Utah, inspiration struck while he was watching a TV special about consummate Renaissance figure Leonardo Da Vinci.

Sometimes great ideas are just sitting out there waiting to happen. For William Provancher, an assistant professor of mechanical engineering at the University of Utah, inspiration struck while he was watching a TV special about consummate Renaissance figure Leonardo Da Vinci.

On screen the actor playing Leonardo was working on a painting with his hand supported by a simple device known as a maulstick. Basically a stick with cloth-covered balls on its ends that is used to support the hand during the painting of fine details, Provancher saw the maulstick as a technology ripe for an update.

“People who have their hands out and up for extended periods of time experience a tremendous amount of fatigue,” he said. “Wouldn’t it be nice to have a local support for your hand that allows you to be able to do things precisely, but to have the ability to have that support wherever you wanted it to be?”

Enter the Active Handrest, a computer-controlled motorized support that uses sensors to follow the users’ wrist movements to provide constant support. While still in development and currently limited to providing support along a two-dimensional plane, Provancher’s technology expands on the historical technology by allowing the support to stay constant even as it moves around the work area.

The prototype machine has been put through a series of tests comparing the performance of users tracing circles with the aid of the Handrest with the performance of the same people tracing freehand, as well as with other fixed supports. Provancher said he’s been pleased by the results but will continue evaluating and improving this technology.

“We find that people are performing more precisely when they’re aided by the Active Handrest,” he said. “however, I want to look more closely at the time-performance trade-offs of the device before we progress too much farther. That said, I feel pretty strongly about the results that we have so far.”

Further developments before commercialization

At this point, Provancher said he feels there will definitely be commercial applications for the technology, although he is still unsure what field will drive the device’s initial commercialization.

The two-dimensional prototype could lend itself to assisting with pick-and-place tasks such as detailed work on circuit boards, wrist rehabilitation, surgery, or painting, but Provancher sees a wider set of applications with further development of the technology.

“One of the more challenging and compelling device improvements we are currently working on is to augment the current device to allow it to move in three dimensions. This will allow our technology to extend to a larger variety of applications,” Provancher explained.

Support in three dimensions would allow the device to be more flexible in how it could be used in far more real world settings, and Provancher said he hopes to be able to extend this technology to the point where it senses the user’s hand movements in all directions and reacts to reposition the support to wherever the hand happens to go whether that is left, right, up, down or any combination. This extension to the planar Active Handrest will allow for general spatial motion while supporting the user’s hand, and would make the device useful for tasks such as sculpting detailed structures.

“This type of general 3-D spatial motion and support is the same exact need that someone in a dental lab would have,” Provancher noted.

While the commercial potential of this technology is apparent, Provancher plans to continue its development in his academic setting for the time being. He is set on refining the functionality and expanding the scope and capabilities of the Handrest, but is keeping an eye out for a potential partner who might help him bring his device to professionals who could benefit from its active support.

“The first place that I would see this would come into application would be in the medical/dental field where there’s demand for this type of high-end performance,” he said. “In the meantime we’re looking for application partners.”

For more information on the Active Handrest, visit Provancher's lab online.

Noah Levine is a senior editor for DPR. Contact him at nlevine@advanstar.com.