App Turns Laser Tweezers into Xbox ‘HoloHands’

Gaming enthusiasts, gather round. There’s a new app in town, and it lets you control optical tweezers from the palm of your hand.

David McGloin and colleagues at the University of Dundee have harnessed the motion sensor of Microsoft Xbox Kinect’s video game platform to manipulate optical tweezers — highly focused laser beams that can trap, move and rotate microscopic particles. Optical tweezers have been used in labs since the 1970s, but finding an interface with which to control them has long proved problematic.

The interface, called HoloHands, allows a scientist to use Kinect to pick up and move micrometer-scale particles seen on a computer screen using hand and arm movements. By waving his hands, a user can create a trapping region to hold the particles, which can be picked up and moved with further arm and hand movements.

“We have a lot of video game enthusiasts here, and we came to the conclusion that Kinect had the potential to allow us to build a very natural and intuitive interface that would appeal to a wide range of potential users,” McGloin said. “We’re always open to new ways of working, and keeping an open mind about these things is essential in science. This shows how technology that at first seems as far removed from the academic lab as it’s possible to be can actually be of great benefit to us.”

HoloHands was tested by moving silica microspheres using the lab’s otherwise standard infrared holographic laser system. It consists of a camera, an infrared laser to measure distance, and a microchip that interprets the data to track people in three dimensions.

Before it can be used for research purposes, the device must be refined to overcome the time lags and misinterpretations of body movement familiar to Kinect users.

“There is great potential as a teaching aid that could show a new generation of students the potential of optical tweezers,” McGloin said. “Optical tweezers and beam manipulation technologies are increasingly found in undergraduate teaching laboratories. The use of a Kinect offers a fairly low-cost interface to control hi-tech equipment and allow interdisciplinary skills to be developed.”

For more information, visit: www.dundee.ac.uk