Most college students today would be lost without the Internet and the unprecedented amount of information, communication and entertainment it puts at their fingertips.

For individuals with motor impairments, however, using a mouse to browse the Web is often impossible. Considering that these individuals might benefit doubly from Internet access, UW researchers are inventing a solution.

Vocal Joystick, a hands-free technology developed by Jeffrey Bilmes, a professor of electrical engineering, and several of his colleagues and students, offers a unique solution.

It allows users to control computer cursors with their voice. Versions of Vocal Joystick have also been created for drawing, playing video games and moving a robotic arm.

Vocal Joystick has been in development since 2003, and the first prototype was released about two years ago. The technology received little media attention at first, Bilmes said. A press release, however, brought Bilmes a flood of inquiries about Vocal Joystick, including an interview with the Discovery Channel.

Vocal Joystick interprets vocal sounds made by the user, such as "aw" or "ee," and the pitch and intensity of those sounds, about 100 times per second.

To simulate the functions of a mouse, the Vocal Joystick translates sounds into a continuous stream of digital commands that move the cursor in certain directions on the computer screen. Consonants like "k" and "ch" simulate pressing and releasing the mouse button.

Bilmes is confident that people can control a cursor with their voice using Vocal Joystick.

"Is it possible to control a mouse with this?" he said. "It's a hands-down, absolute 'yes.'"

Various trials and demonstrations, some of which are viewable as videos on the Vocal Joystick Web site, have shown that people can indeed use the program to control a cursor accurately and effectively.

The initial learning curve for Vocal Joystick is short, said Richard Wright, the director of the UW's Linguistic Phonetics Lab, who has worked closely with Bilmes on the project.

Wright said there is a calibration period of about two to three minutes, during which the program gets to know a user's voice as the user gets to know the program. He said that most children can use Vocal Joystick to control a cursor after a few minutes. It takes adults slightly longer to learn.

The developers of Vocal Joystick believe they have just scratched the surface of the technology's applications. Possible future developments range from hands-free control of wheel chairs and domestic devices to hazardous waste handling and military uses.

"Anything you can attach to a computer that you want to move continuously, you can use [Vocal Joystick] for," Wright said.

Other hands-free devices have been in use for years, but the developers of Vocal Joystick claim the technology has many advantages over its predecessors. Speech-recognition devices, for example, rely on specific verbal commands.

"It would be very slow to move a cursor using discrete commands like 'move right' or 'go faster.' The voice, however, is able to do continuous commands quickly and easily," Blimes said in a statement.

Speech recognition devices must be designed to interpret a certain dialect of a certain language.

In this respect, the Vocal Joystick is more inclusive. It relies on basic sounds most humans naturally make.

"Anybody can say 'yaww' or 'aww,'" Wright said.

Other hands-free devices include a sip-and-puff device and a tongue-paddle, which must be held in the mouth and spit out when the user wants to talk or move to a different task. These devices can be cumbersome and raise sanitary concerns. Technology that traces and interprets eye-movement requires the user to wear a headset and is considerably more expensive than the Vocal Joystick.

The only equipment needed to use Vocal Joystick is a microphone, a computer with a sound card and the device's software program.

The technology's feasibility is matched by its accessibility.

"Any person who has a functioning vocal tract, even with pretty degraded speech abilities, can use [Vocal Joystick]," Bilmes said.

[Reach contributing writer Jacob Olson at development@thedaily.washington.edu.]