Controlling biorobotics

Those who know me well know that I’m not the most outdoorsy person. Bugs aren’t on the top of my list of favorite things, and quite frankly, I am proud of my cat when she successfully catches one in the house. And cockroaches ─ forget about it!

Now, despite my distaste for creepy crawlies, I couldn’t help but get lured in by a recent headline from the University of Connecticut: “A cyborg cockroach could someday save your life.” Honestly, it’s the word “cyborg” that got me.  But the news was quite interesting.

According to the article by Colin Poitras, Abhishek Dutta, an assistant professor of electrical and computer engineering who specializes in control system optimization and cyber-physical systems, has been a part of an effort spanning the past decade to explore biorobotic platforms for insects. Although research has been in progress, the tiny technology is still hit-and-miss, with a 50% success rate.

“The use of insects as platforms for small robots has an incredible number of useful applications, from search and rescue to national defense,” Dutta said in the article.

Recently, Dutta and undergraduate Evan Faulkner, have created a microcircuit allowing reliable and precise control of a Madagascar hissing cockroach. Unique to their development, the microcircuit provides improved movement control, real-time feedback of the response to stimuli, and “multi-channel avenues for stimulating the insect’s nerve tissue,” which together culminates in more precise control.

“To improve control of the insect, Dutta’s microcircuit incorporates a nine-axis inertial measurement unit that can detect the roach’s six degrees of free motion, its linear and rotational acceleration, and its compass heading,” Poitras explained in the article. “Another feature that Dutta and Faulkner added is the ambient temperature surrounding the creature, because tests have shown that the temperature of the environment in which a roach is moving can affect how and where the insect moves. Roaches, for the record, are more likely to go for walks when it’s warm.

“The microcircuit Dutta and Faulkner created is part of a small electronic ‘backpack’ that can be strapped to the back of a cockroach,” he continued. “Wires from the device are attached to the insect’s antennae lobes. A tiny Bluetooth transmitter and receiver allows a nearby operator to control the roach’s movements via an ordinary cellphone. Sending tiny electrical impulses to the nerve tissue in the insect’s right or left antenna lobes makes the insect believe it has encountered an obstacle. A small charge to the left antenna makes the insect move away to the right. Likewise, a charge sent to the right antenna makes the insect move left. It’s power steering redefined.”

The microcontroller features a built-in potentiometer, which allows the operator to vary stimuli voltage, frequency and cycle, Poitras reported. The researchers found that 1.2V amplitude, 55 Hz frequency and 50% duty cycle resulted in the best response from the insects.

The Bluetooth connectivity proved essential, as it allowed the operators to use real-time feedback to set parameters for stimulation, thus allowing the operators to precisely steer the cockroach.

“Our microcircuit provides a sophisticated system for acquiring real-time data on an insect’s heading and acceleration, which allows us to extrapolate its trajectory,” Dutta explained in the article. “We believe this advanced closed loop, model-based system provides better control for precision maneuvering and overcomes some of the technical limitations currently plaguing today’s micro robots.”

As with every technical step forward, the advancements came along with lessons to help influence future research. The University of Connecticut researchers found that the initial stimuli to a lobe provided the greatest response from the cockroaches for that lobe, meaning the most dramatic change in the respective direction, which each following response from stimuli to that lobe decreasing in intensity.

Although I’m not sure I’ll experience a change-of-heart toward cockroaches anytime soon, maybe once this technology becomes more effective I’ll come around.