Transforming plain surfaces into low-cost touch screens
10 July 2013
Introducing 'STATINA' - a low cost system that can turn a whiteboard, glass window or even a wooden table top into a responsive, touch sensitive surface.
Assistant Professor Andy Khong (right) with his undergraduate student Zaw Lin, demonstrating the tracking capabilities of their prototype
Developed by researchers at Nanyang Technological University (NTU) in Singapore, the new technique is based on the principles of vibration and imaging and is able to track the movements of multiple fingers and of objects.
Retrofitting the system on existing flat-panel TVs will transform them into new, touch sensitive display screens, at only a fraction of the cost of new touch-sensitive display screens.
Once hooked up to a computer, the modified TV screens can then be used as interactive billboards, mall directories and even as a digital whiteboard which can track what is drawn or written.
NTU Assistant Professor Andy Khong, who led the research, says this award-winning system has been proven on different types of large surfaces.
“Our innovative system is able to transform surfaces such as wooden tables, aluminium, steel, glass and even plastics into low-cost touch screens. It means in future, you could play computer games or draw sketches on walls or windows since almost all surfaces can be made touch-sensitive with our system,” says Prof Khong.
Named STATINA (Speech Touch and Acoustic Tangible Interfaces for Next-generation Applications), this interdisciplinary research project exploits principles of vibration waves propagating on a solid surface.
By using a few low-cost vibration sensors and a specially developed algorithm, the system can pinpoint the location of a light tap on any surface. When further equipped with low-cost web-cameras, this system can also track the movements of multiple fingers or objects on any surface.
Since sound waves propagate through matter at a certain speed, it is possible to derive the location of the touch based on when each sensor picks up the signal, Prof Khong added.
In addition to understanding the mechanics behind solid wave propagation, the scientists had developed a novel signal processing algorithm to determine the exact location of the initial point of impact.
STATINA is the culmination of Prof Khong’s research spanning the last four years. He and his team of researchers are now working to commercialise their invention by developing a more compact system and expanding its capabilities to include tracking of fingers and stylus movements using optical cameras.
So far, they have tested their system on surfaces such as wooden tables, aluminium, steel, glass and plastics.
The team won the Engineering Achievement Award 2012 for this development, presented by The Institution of Engineers Singapore (IES) last December.