Engineering at Nebraska, Spring 2007
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Magic in the Making

Lance Perez
Lance Pérez
Photo by Erik Stenbakken

Lance Pérez hopes someday, assistive technology will make it more feasible for someone to live at home after a debilitating accident or illness.

The associate professor of electrical engineering is developing an ad-hoc wireless sensor network that could help someone perform simple household tasks like opening a window or turning on a lamp. It could even help families monitor their loved ones from a distance.

“I’ve always had an altruistic approach to engineering,” Pérez said. “Good engineering, I think, improves the human condition. I’ve always believed that.”

Pérez said for someone who wrote a graduate thesis on interplanetary science, his foray into biomedical engineering has been a pleasant surprise. His journey began in the late 1990s when he joined the Madonna Magic, a National Wheelchair Basketball Association team sponsored by Madonna Rehabilitation Hospital. He became friends with several Madonna employees, and when the hospital opened the Institute for Rehabilitation Science and Engineering in 2001, he was asked to help with research.

“I’ve seen the struggles people have to achieve independence and maintain quality of life, and it struck me that science and engineering wasn’t being fully utilized in this application,” Pérez said.

Mark Hakel, director of education and staff development at the Institute for Rehabilitation Science and Engineering, studies the conditions that prevent a stroke or trauma patient from returning home. He said Pérez has a knack for identifying technology that could help someone live independently.

“Lance often tells me that he relies on us to figure out the clinical needs, and he can figure out how engineering can be used to reach that final goal,” Hakel said.

In this case, Pérez said, some of the technology existed before researchers discovered that it could be used to control someone’s home environment. Steve Goddard, associate professor of computer science and engineering, helped design the realtime sensor system.

Lance Perez
Lance Pérez
Photo by Erik Stenbakken

“Then we said if you put it into the home of an elderly or disabled person, or in an assisted living facility, what could you do to increase independence and quality of life?” he said.

Pérez envisioned creating a system that was inexpensive, easy to install and could communicate wirelessly. He sought advice from Gregor Henze, associate professor of architectural engineering, who is an expert on environmental control systems.

To test the application, Pérez constructed a laboratory in the Walter Scott Engineering Center to mimic someone’s home. He and his students installed sensors throughout the “smart room.” The person for whom the system is designed also wears a band containing a sensor. The sensors communicate with each other and with a master control panel. An intelligence system within the control panel analyzes data patterns to detect the person’s location within the room. The system also collects various environmental readings, such as the temperature inside and outside the room and which lights are turned on.

“Someone in, for example, Christopher Reeve’s situation can communicate with the system to open the windows and the computer would know which one to open based on the person’s location,” Pérez said.

Or, the user could say, “I’m cold,” and the system would decide whether to adjust the temperature by opening the blinds, closing a window or turning up the thermostat.

Pérez’s research is only two years old. He said the ideal product would have more advanced communication capabilities.

The most pressing need is developing a “reasonably accurate” 2-D positioning system into a realtime 3-D localization system, he said.

Pérez also envisions a system that could give the user directions to get from one room to another, which would be useful for people whose thought processes have changed as the result of a stroke.

The system also could track medical conditions, which would help doctors better diagnose health problems, Pérez said. It also is designed to wirelessly communicate with common biometric devices like a blood pressure machine.

A system with diagnostic capabilities would help families and medical professionals track changes in someone’s health, he said. Studying someone’s walking pace could indicate whether he or she is at risk for a heart attack. The system also could give clues to signs of depression, such as lack of activity or changes in sleeping patterns.

“Assistive technology allows you to start addressing a set of cognitive and physical conditions that might have gone undetected before,” Pérez said.

Madonna’s Hakel hopes the system will bridge the distance between family members. He said stroke patients who don’t have a close relative living nearby are much more likely to live in an assisted living or long-term care facility.

Pérez said the system could connect to the Internet and allow family members to monitor their loved ones throughout the day. “What we’re hoping is that this will extend that safety margin so people can return home and stay there longer,” he said.

Hakel said Madonna is still figuring out how it could monitor patients from a remote location and still respond quickly if someone were sick or hurt.

“We just don’t know yet, not with the population we serve,” he said. “What we do know is that if we can prevent someone from being institutionalized, in the long run that would save you and I a lot of money.”