Spidey senses and flying robots

Imagine the possibilities if drones and self-driving cars possessed Spider-Man’s tingly “spider senses.” It would allow them to detect and avoid objects more accurately by processing sensory information faster, says Andres Arrieta, an assistant professor of mechanical engineering at Purdue.

Current sensor technology doesn’t process data as fast as nature does. Therefore, Purdue researchers have built sensors inspired by spiders, bats, birds and other animals whose actual spidey senses are nerve endings (mechanosensors) linked to special neurons (mechanoreceptors). The nerve endings appear as hair, cilia or feathers, and only process information essential to survival.

Located on the legs, a spider’s hairy mechanosensors filter environmental data according to thresholds like pressure changes. When a spider’s web vibrates at a frequency associated with prey or a mate, the mechanosensors detect it, generating a reflex in the spider, which then reacts quickly. The idea is to integrate similar sensors into the shell of an autonomous machine, such as the body of a car, which could help prevent auto accidents from human error.

Researchers designed these sensors to use on/off states to interpret signals, with an intelligent machine able to react accordingly. “With the help of machine-learning algorithms, we could train these sensors to function autonomously with minimum energy consumption,” Arrieta says.

Purdue researchers have also engineered flying robots that behave like hummingbirds, trained by machine learning algorithms based on techniques the birds use naturally.

After learning from a simulation, the robot “knows” how to move about independently like a hummingbird would, such as discerning when to perform an escape maneuver. Although the robot can’t yet see, it senses by touching surfaces. 

“The robot can essentially create a map without seeing its surroundings. This could be helpful in a situation when the robot might be searching for victims in a dark place — and it means one less sensor to add when we do give the robot the ability to see,” says Xinyan Deng, an associate professor of mechanical engineering.

While conventional aerodynamics prevent drones from being made infinitely smaller, researchers have built flying robots as small as insects. This facilitates greater wing-flapping frequency and flying efficiency.