"We build by observing nature," says the creator of a robotic hummingbird

Nature confirms its perfection whenever a new robotic development emulates some of its many components. How do you explain that a large part of robots mimic humans and animals almost unchanged from the "originals", which can inject impossible abilities for living beings?

The work of Xinyan Deng, professor of mechanical engineering at Purdue University, Indiana, USA, expands the catalog of bio-inspired robots. In this case, the muse It's the hummingbird.

Why choose the hummingbird among the many creatures of nature? "It is a unique species, halfway between insects and birds, summer is coming and it is possible to see them in your yard running and chasing each other. They can float like insects by flapping high frequency wings and flying acrobatically like birds by transforming its wings, "says Deng in dialogue with TN Tecno.

"Most birds do not float, while most insects can not actively deform their wings, hummingbirds can do both, and their flight is stable and agile. little wonders of nature. The hummingbird is the perfect animal to study, "says the representative of a multidisciplinary team that created this small insect fly that weighs only 12 grams, just like a real hummingbird.

– When did you start thinking about Flappy, the hummingbird that you developed?

– My lab has been working on low-speed flight dynamics and control for many years. Our work includes the aerodynamics, dynamics and control of insect flight, as well as the design of bioinspired robots.

More specifically, our work on hummingbirds began a few years ago with a grant. We started working with a hummingbird biologist, Professor Bret Tobalske from the University of Montana, to collect flight data for several summers. So, we started building hummingbird robots using the principles we learned from nature.

– His research team studied the bird in an exhaustive way. What did you learn in these observations and how did you bring them to the robot?

– As I said, in collaboration with our biologists, we conducted experiments on hummingbirds for three summers. The bird is temporarily placed in a flight camera and we use three high speed cameras configured to capture its instant kinematics of the movement of the fins and body.

Based on the flight data extracted from the cameras, we designed a dynamic model and studied flight control strategies in different response behaviors. That is, how they move their bodies and wings to achieve certain flight performance.

– How does the artificial intelligence system used for this machine mimic the theft of hummingbirds?

– This develops throughout the experience. Depending on the behavior of the hummingbird escape flight, we train the robot using automatic learning methods. The reinforcement learning results in a kinematic of body movements very similar to that of the royal hummingbird during the escape maneuver. We transferred this to the robot for validation of the experiment.

– What uses will this robot have?

– Primarily, the ability to float means that it can be used in tight or confined spaces. For example, during searches and rescues in collapsed buildings. We also made a version weighing less than 1 gram: it can now take off and we are working on its flight controls. These small robots have access to even narrower spaces and are even used in indoor environments.

– What are the next challenges? Do you plan to put a battery so that the robot does not have to fly "attached" to a cable?

– Yes, we test the battery on board and the initial test was a success. For flying robots, one of the challenges is the power density of the battery, which limits the duration of the flight like other drones. The robot weighs 12 grams without the battery and can support up to 27 grams of weightSo there is room for the battery and other sensors, like a small camera, for example.

In addition to installing the batteries, the following steps consist of equipping other sensors for navigation. In the meantime, we can also use this type of robot to work as experimental platforms parallel to biological systems and to study some of the badumptions we have about animal theft.

The current version of Flappy, as it was named, does not have a camera. However, you can map a site using its wings. When they collide with walls or columns, they are detected and transferred to a graph.

"The robot can create a map without seeing what's around it. This would be useful in a situation where the robot could look for victims in a dark place"Explains Deng, who is advancing the possibility of including in the future more vision systems in this hummingbird, whose interior does not contain blood but electrical circuits.