Some rats’ movements at the Downstate Medical Center in Brooklyn are being directed by remote control.
By pressing a PC’s cursor-control keys, radio signals are transmitted to the backpack worn by the rodent and electrical impulses are sent to the parts of the brain that register sensory input from whiskers.
Neuroscientists here have taught the rat to go left when brain’s left-whisker area is stimulated, and right upon a right-side tweak. When the animal moves as directed, they stimulate her brain’s “reward” center through a third wire. The most important thing rats are learning is that explosives have yummy aromas.
“Roborats” may someday become little spies that can be guided into a building and then roam freely to sniff out explosives, toxic chemicals, or other bad stuff. The team at the Brooklyn center has even mounted tiny cameras on roborats’ backs, enabling remote handlers to see where their furry operatives are going —and what they’re finding.
Most of the studies on non-dog sniffers have been funded by DARPA.
Previously, DARPA asked W. Joe Lewis, a Department of Agriculture scientist, if parasitic wasps could be used like dogs. Researchers devised a handheld container with a hole through which outside odors are wafted. Inside, wasps previously taught to love the odor of an explosive are monitored with a tiny camera linked to a computer. The system registers when the insects cluster near the hole, showing they’ve gotten a whiff of bomb stuff. Now the team is seeking backers to commercialize the work.
Meanwhile, DARPA-funded University of Montana researchers have taught honeybees to associate the odor of explosives with sugar water. The group use the trained insects as land-mine finders. The bees are turned loose, then a radar-like system bounces laser light off them to show where they tend to cluster. The team was able to locate several defused land mines at a U.S. Army test site, according to a 2003 report.
DARPA grantee Atto Bioscience has installed genes for mammalian olfactory receptors in the one-celled microbes. With additional gene implants, the team hopes to get the altered yeast cells to light up like tiny fireflies when they “smell” explosives.