Global Positioning Systems are appearing in every kind of device imaginable nowadays — in cars, on cell phones and, in the future, maybe even home medical equipment.
Although it's not ready for users just yet, a group of students at Weber State University in Ogden, Utah, has developed a GPS-guided wheelchair that can drive itself to preprogramed locations.
The futuristic power chair was created as part of a senior project by computer electronics engineering technology majors Scott Cornford, Pat Gay and Joe Patterson.
Cornford, who works for the Federal Aviation Administration and graduated from the university this spring, came up with the idea because of his interest in robots and GPS. “I was just after a small vehicle to control,” says Cornford, who notes he was not originally considering the practical uses of the technology when he settled on a wheelchair. But after beginning the project last year, he said he has realized that the device could benefit the lives of disabled people — especially those who are limited to straws or voice commands to control their chairs.
“For a paraplegic, having GPS would be a real boon — just saying, ‘Hey, take me to the grocery store’ and having [the wheelchair] do that for them,” he explains.
Gay, who focused on interfacing the software and hardware, says the applications are limitless. “If the person has a regular routine, they can program where they want to go, and sit and ride,” she says. “It would be great for those who are homebound not to have to have a full-time caretaker there just to get from point A to point B. It would give them more mobility.”
For this project, Cornford started with an Invacare Action Ranger X with two 1.6 horsepower motors, two laptops attached and a 24-volt DC battery. After the laptops acquire the wheelchair's position from the GPS, they send information to the motor controller, which then sends adjustments to the motors. There is also a gyroscope in the chair to prevent tipping.
The GPS receiver uses Wide Area Augmentation System — technology the FAA is developing for planes to use when making runway approaches — which makes the system accurate within 3 meters or less.
“This is really cool stuff,” says Cornford.
Currently, Gay and Patterson are tweaking the chair to enhance the guidance system and add obstacle detection, something Gay says is sorely needed. “In the enhanced version it will detect an object and decide if it can go left or right or if it needs to back up.”
There are no immediate plans to market the device, but Cornford said he already has several ideas in mind. In addition to outdoor GPS, indoor GPS — which uses radio transmitters around a room — could be used in settings such as a hospital to take patients to different areas of the building, such as to the X-ray room or to get therapy. “You could set it up so [patients] could be a little more independent,” he says.
