Robots, already deployed by the military to replace the eyes and ears of uniformed personnel, will soon be using similar skills to perform search and rescue missions in rubble piles across America.
But unlike their military clones, robots working on home soil may suffer from a failure to communicate.
According to a test performed by the National Institute of Standards and Technology (NIST), having too many of these life-saving robots could lead to crossed signals, garbled radio transmissions and a degraded ability to perform needed search and rescue missions.
Kate Remely, leader of the wireless systems metrology project at NIST, explained that while military robots are each allocated specific frequencies, manufacturers for urban search and rescue robots use the unlicensed industrial, scientific and medical (ISM) band used by most commercial electronic devices.
“There are a lot of robots trying to use the same frequency slots,” she told internetnews.com.
“It’s certainly not an insurmountable problem, but it needs to start being considered by the manufacturers,” she added.
Remely said the manufacturers have been focused on other features, such as mobility, visual acuity and manipulator dexterity, to an extent that “wireless capability has been almost an afterthought.
The field tests of 14 robots, conducted near Gaithersburg, Md., over “fairly large spaces” showed that transmissions from other systems caused 10 of the 14 robots to stop functioning altogether.
The tests, which were sponsored by the Department of Homeland Security, also showed that neither use of ISM frequency bands nor adherence to protocols designed to minimize interference between systems in the bands could guarantee flawless communication between a robot and its human operator.
Radio interference could happen whenever the ISM frequency bands became crowded or when one user had a much higher output power than the others.
An example of the latter problem occurred during the tests when transmitters in the 1760 MHz band knocked out video links in the 2.4 GHz frequency band.
In another case, a robot using an 802.11b signal in the 2.4 GHz band overwhelmed and cut off a robot that had been transmitting an analog video link at 2.414 GHz.
Remely said there are a number of ways to improve urban search and rescue wireless communications.
Options, some of which are currently being investigated by robot manufacturers, include changes in frequency coordination, transmission protocols, power output, access priority, and using relay transformers to increase the range of wireless transmissions.
Most of these remedies will require some coordination between the robot manufacturers, but Remely said the manufacturers didn’t seem too competitive to be able to play together.
“It’s just that the manufacturers never have the chance to get together with a bunch of other users — that’s one of the real benefits of these field exercises,” she said.
