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CS Alumnus Turns Phone into Pen

9/17/2009 6:22:00 AM

University of Illinois alumnus Romit Roy Choudhury was recently profiled by The Guardian for his groundbreaking prototype of an electronic pen that uses smartphone accelerometers to translate gestures into writing.

From The Guardian:

“Ever tried waving your mobile phone around in the air for a better signal? Of course you have. But if you see assistant professor Romit Roy Choudhury of Duke University in North Carolina doing so, he’s not battling poor reception. He’s using his phone as an electronic pen to write reminder notes.

In 2005, Mr Choudhury was a PhD student at the University of Illinois working on computer science. Often forgetting things, he wanted to have an easy way of jotting information down.

‘‘I envisioned having a pen with a wireless interface and an accelerometer. My idea was to be able to write in the air with the pen and click a button to email the handwriting to my email address. Such pens were unavailable, and I shelved the idea,’’ Mr Choudhury says.

Since moving to Duke, he’s revisited the concept, thanks to accelerometers in the latest smartphones. An accelerometer senses positional changes: it’s what prompts the screen image to flip from portrait to landscape when the phone is turned sideways. It also enables games with repetitive movements.

‘‘At that point, I had the idea of using the phone as a pen, since the phone has both the accelerometer and the wireless capability,’’ Mr Choudhury says. ‘‘My students jumped on to the idea and did a wonderful job of turning it into a good prototype. This first round of prototyping took around six months.’’

So what are the remaining challenges for the device, now dubbed the PhonePoint Pen by the researchers? Correcting mistakes when writing is an obvious one — the idea is to allow users to choose a movement that means ‘‘delete’’, such as several horizontal shakes. When writing on the move, the phone’s accelerometer picks up your movement as well as its own, distorting the output. Better algorithms, more sophisticated built-in accelerometers and a gyroscope would all help.

Air writing is useful for noting where you left the car or jotting down an appointment time. Following recent interest from the medical profession, Mr Choudhury also thinks it might help people with poor finger control or speech problems.”

Read the complete article at: http://www.guardian.co.uk/technology/2009/sep/09/phonepoint-pen-gesture-recognition