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Most people suffering from multiple sclerosis or spinal cord injuries can still move their eyes because they are directly connected to the brain. Some existing technologies already allow severely disabled people to stare at arrows on a computer and direct the movement of a wheelchair.
But there are problems with that system, including a delay between the movement of the eyes and the wheelchair.
"Current tracking software often uses a screen-based system where you have a screen open and you look at locations on the screen. The problem with that is that it's very simplistic and also diverts the users' attention from the outside world and therefore there's more risk of not noticing obstacles or other things in the way," said Kirubin Pillay, a PhD student at Imperial College London.
A team led by Aldo Faisal at Imperial College London has developed software that allows users to maneuver the chair just by looking in the direction they want to take.
"Our eyes are not only a window into our soul, they're also a window to our intentions. So if you want to go somewhere, for example if I want to go there, or go there, I will look there and I will look there in a specific manner, and we can build a computer system that can decode our eye movements, and so we observe eye movements with an eye tracker, and we then try to make sense of them, and the computer interprets these commands and drives the wheelchair accordingly,” said Fasial.
Two cameras trained on the eyes observe their movements and can determine whether a patient is merely looking around or wants to move in a certain direction.
"So essentially we track the pupil of the eye and via a calibration process, we relate that to where the subject's looking in the world around them," explained William Abbott, a researcher at Imperial College London.
Visual information detected by cameras is analyzed by algorithms within 10 milliseconds and translated into instructions for movement that's almost instantaneous.
The camera-based system costs only about $85 because most of the work is done by the algorithms. No expensive hardware is needed. The London team hopes to make the system commercially available within three years.
task 2Michelle Howard received her fourth star at a ceremony at Arlington National Cemetery with her family and fellow servicemen looking on.
"If you don't believe today was the first - when I called to order, a four-star shoulder board for women - they didn't exist. [A] special contract was let and you folks are seeing the first set in the history of the United States Navy," said Howard.
Secretary of the Navy Ray Mabus was the promoting officer.
"The Navy picked the best officer to be the VCNO. That's the only thing that happened here today," said Mabus.
Since 1982, when she graduated from the U.S. Naval Academy, Howard has achieved many historic "firsts" in her career. She was the first African-American woman to achieve three-star rank in the U.S. Armed Forces, as well as being the first woman to achieve the rank of admiral in the Navy. She also was the first African-American woman to command a naval ship.
Chief of Naval Operations Jonathan Greenert said the honors mean extra obligations.
“She will bear the burden of a role model, and she is ready to bear that very well, and I am very excited about that because we need lots more women in the Navy,” said Greenert.
Howard was in the Pentagon during the September 11, 2001 terrorist attack, and in 2009 participated in the naval task force dispatched to rescue the U.S.-flagged merchant vessel Maersk Alabama and its captain Richard Phillips, who had been kidnapped by Somali pirates.
"I was just three days in the job when we got word that Captain Philips had been kidnapped," recalled Howard.
American women serving in the military have broken many barriers in recent years, and can compete for positions that were once were closed to them. Howard said her promotion can serve as further encouragement.
"My rank today lets them know that they can go from junior enlisted to MCPON (master chief petty officer) in the Navy or from ensign to admiral," said Howard.
Howard is the third woman in the U.S. military to reach a four-star rank. One is in the Army and the other in the Air Force.
“We, as a Navy and as a nation, have just got to quit wasting the talent and the ability based on race or gender or anything else," said Mabus.
Officials from all military service branches have announced plans to open combat positions to women who meet physical or performance standards by 2016.
