Remote-controlled Roaches

Daily News Article   —   Posted on September 13, 2012

(by John Roach, NBC News) – A team of researchers at North Carolina State University has found a way to control the movements of cockroaches through electrical signals and believe it could help find people trapped in collapsed buildings and other disaster zones unnavigable by humans.
 
The researchers see remote-control cockroaches as an alternative to small-scale robots. Building practical, insect-sized robots able to squeeze through tightly packed rubble has proven difficult because of the large batteries needed to power them.  Cockroaches are experts at navigating hostile environments, according to researcher Alper Bozkurt, an electrical engineer at North Carolina State University.  “They come with biological autonomy to help them survive and this, if carefully controlled, helps them to respond to uncertain and dynamic conditions of certain scenarios such as searching for survivors after an earthquake,” he says. 
 
Bozkurt, working with doctoral candidate Tahmid Latif, communicated with Madagascar hissing cockroaches by saddling them with electrical devices that look like backpacks. Each insect backpack included a thin, rigid, printed circuit board with a microcontroller, a wireless signal receiver, miniature plugs for connecting stimulation electrodes and a lithium-ion polymer battery.
 
“What we do is similar to riding a horse,” Bozkurt says. “[The] cockroach walks naturally, and we simulate barriers by sending pulses to its antenna. They use their antenna as touch sensors, so stimulation on one side directs these insects towards the opposite direction.” Bozkurt and Latif presented their research last month at the 34th Annual International Conference of the IEEE Engineering in Medicine & Biology Society in San Diego, Calif.
 

Bozkurt and Latif attached the backpacks to the roaches using magnets that they glued to the insects’ backs. They used tiny stainless steel electrodes to connect the backpack’s circuit board to the roach’s antennae and fixed them in place with medical-grade epoxy, according to Bozkurt. The researchers then wirelessly sent electrical impulses to the backpack’s receiver, which stimulated either the left or right antenna.  The greater the electrical charge, the more sharply the roaches changed direction.
 
The researchers say they programmed the microcontroller with an algorithm to monitor the amount of voltage induced into the roach’s neural tissue in order to keep from damaging that tissue and making it unresponsive to stimulation pulses.
 
They also attached a sensor to the roaches’ abdomen (cerci) “which senses if there is a predator trying to reach from behind. When they feel something, they just go in the forward direction to run away from the predator,” Bozkurt explained.  “So, we use that to make the insect go forward and antenna electrodes to make it go left and right.”
 
In case all this shocking of cockroaches makes you feel sorry for the insects, Bozkurt said not to worry. “Insects do not have the concept of pain…they have sensors that direct their reflexes, but they don’t have pain sensors,” he said.  
 
So far, the team has successfully demonstrated the technology works. The video [under “Resources” below the questions] shows a cockroach being steered along a curvy line in a hallway.
 
Bozkurt and Latif’s next step is to miniaturize the backpack even further and gain more precise control of movement.  Also, the team aims to create more real-life scenarios and work on communicating with the cockroaches under, for example, piles of rubble.
 
“Right now we have direct line-of-sight communication,” Bozkurt said. “But when you are trying to save people, there will be a lot of material between our transmitter and the antenna on the insect.” …
 
This post is a combination of news reports from NBC News and CBS News local Charlotte.  Reprinted here for educational purposes only. May not be reproduced on other websites without permission from NBC and CBS.