Sensors the size of quarters — and eventually the size of dust particles — may soon be used to map burning buildings, track battlefield movements and monitor hospital patients from afar.

Wireless sensor research at Iowa State began this semester, with 25 sets of sensor equipment available to different departments for study.

The sensors, or “Motes,” being researched at Iowa State are able to receive and transmit information to a computer base, but they still need a lot of work before they can be used commercially, said Daji Qiao, assistant professor of electrical and computer engineering who is working with the sensors.

“Each sensor is like a mini computer,” Qiao said. “It has data processing and transmitting capabilities.”

The sensors can collect data from the environment with seven different sensors, he said, including temperature, light, movement (both vertical and horizontal), moisture, sound, and magnetic properties. Each sensor collects data in the area around it and reports the information back to a computer base, usually a laptop.

There are two types of sensors, one the size of a matchbox and one the size of a quarter.

“Those sensors will become smaller and smaller,” Qiao said. “The idea is to make it like a dust [particle] floating in the air. That’s the future.”

The sensors can be helpful in many ways, from firefighting to agriculture.

Sensors can be thrown into a burning building to help firefighters rescue victims; they can be tossed onto a battlefield for surveillance; they can be used to monitor hospital patients; they can be scattered around a corn field to gather information on soil temperature and moisture.

“You cannot deploy real people out to measure these sorts of things,” said Srikanta Tirthapura, assistant professor of electrical and computer engineering who is also working with the sensors. “You can use sensors to measure them, and the sensors can relate back to a base by a series of wireless links. So that’s what makes this very powerful.”

The concept of wireless sensors began in the military, and research has recently been applied to other areas where tiny data transmitters can be beneficial, Qiao said.

However, the sensors are used mainly in research studies because they are still being tested. They are very fragile, can be easily damaged by the environment and are powered by batteries so they have a limited amount of power, Tirthapura said.

“Right now it’s only for experimental purposes,” Qiao said. “There’s a lot of work to do.”

The sensors are currently $400 per set, but Qiao predicts they will get cheaper with time, to around $1 per set.

More than $10,000 has been spent to study the sensors in several departments this semester. The main research occurs within the electrical and computer engineering department.

“There’s some research going on in the civil engineering department,” Qiao said. “They deployed 40 sets of sensors in a bridge in Des Moines and tried to extract all kinds of information from this bridge.”

Measuring the stability of buildings and bridges is one of many ways the sensors can be used, Tirthapura said. There are numerous possible applications, ranging from domestic to professional.

Wireless sensors can be used for surveillance to track intruders; they can be used to keep close watch on environmentally sensitive land and reduce fire and earthquake damage. Sensors can also be attached to power lines, and if a line is broken, the section can be shut down immediately to prevent widespread blackouts like those that occurred in the summer of 2003.

Eventually the sensors will be small enough, strong enough and cheap enough to be used widely for these purposes, Qiao said.