Every year at about this time, German automation company Festo announces its newest animal-inspired robots.
Last year it was a kangaroo (we had to double check that it wasn’t an April Fool’s joke), and before that, a seagull, dragonfly, and floating air jellies, among other cool things. For 2015, Festo is introducing two new insectoid robots: cooperative ants and swarming butterflies.
The theme of Festo’s “Bionic Learning Network” program this year is “Join the Network,” and their flagship projects are both based around swarms of small robots that mimic the way insects work together and interact with each other.
BionicANTs are intended to demonstrate cooperative behavior based on a natural model. Like real ants, the BionicANTs follow sets of simple rules and can operate autonomously, while at the same time working together to complete large scale, complex tasks.
The ants communicate between themselves to coordinate their actions and movements, and small groups of them can manipulate objects much larger than themselves by pushing and pulling together.
In terms of hardware, the ants are largely 3D printed (laser sintered), and the electronic circuits on the outside of their bodies (the circuit lines are functional, not decorative) are also 3D printed.
They have a 3D stereo camera system in their heads, and their antennae actually work as battery-charging contacts when pressed against a powered rail. Moving parts like legs and mandibles are made of a total of 20 “trimorphic piezo-ceramic bending transducers,” which move rapidly and efficiently while remaining durable with minimal space requirements.
An optical sensor (like you have in your computer mouse) underneath the ants allows them to navigate using infrared markings on the floor, and their cameras can also localize based on landmarks. Each ant is 13.5-centimeter long and weighs 105 grams.
Festo has made plenty of biologically-inspired flying robots, but these butterflies have to be some of the most beautiful. Each one is autonomous, using independently controllable wings to steer itself and fly preprogrammed routes.
The technology that Festo is demonstrating here will be familiar to anyone with indoor micro aerial vehicle experience: to keep the butterflies from crashing into one another (or into walls), they’re being continuously tracked by 10 high-speed (160 fps) infrared cameras mounted in fixed positions around their flight area. A pair of active infrared beacons on each butterfly takes the place of the round reflectors that you see on many indoor quadcopters.
Each butterfly has a 50-centimeter wingspan and weighs just 32 grams, but carries along two servo motors to independently actuate the wings, an IMU, accelerometer, gyro, and compass, along with two tiny 90-mAh lithium-polymer batteries.
With a wing beat frequency of between 1 and 2 flaps per second, top speed is 2.5 m/s, with a flight time of 3 to 4 minutes before needing a 15 minute charge. The wings themselves use impossibly thin carbon rods for structure, and are covered with an even thinner elastic capacitor film.
According to Festo, “as the wings slightly overlap, an air gap is created between them when they beat, which gives the butterflies their special aerodynamics.”