One huge advantage of drones is that these little robots can go places where people can’t, including areas that might be too dangerous, such as unstable structures after a natural disaster or a region with unexploded devices.

Researchers are interested in developing devices that can navigate these situations by sniffing out chemicals in the air to locate disaster survivors, gas leaks, explosives and more. But most sensors created by people are not sensitive or fast enough to be able to find and process specific smells while flying through the patchy odor plumes these sources create.

Now a team led by the 91探花 has developed Smellicopter: an autonomous drone that uses a live antenna from a moth to navigate toward smells. Smellicopter can also sense and avoid obstacles as it travels through the air. The team Oct. 1 in the journal IOP Bioinspiration & Biomimetics.

“Nature really blows our human-made odor sensors out of the water,” said lead author , a 91探花doctoral student in mechanical engineering. “By using an actual moth antenna with Smellicopter, we’re able to get the best of both worlds: the sensitivity of a biological organism on a robotic platform where we can control its motion.”

The moth uses its antennae to sense chemicals in its environment and navigate toward sources of food or potential mates.

“Cells in a moth antenna amplify chemical signals,” said co-author , a 91探花professor of biology who co-supervises Anderson鈥檚 doctoral research. “The moths do it really efficiently 鈥� one scent molecule can trigger lots of cellular responses, and that’s the trick. This process is super efficient, specific and fast.”

The team used antennae from the Manduca sexta hawkmoth for Smellicopter. Researchers placed moths in the fridge to anesthetize them before removing an antenna. Once separated from the live moth, the antenna stays biologically and chemically active for up to four hours. That time span could be extended, the researchers said, by storing antennae in the fridge.

By adding tiny wires into either end of the antenna, the researchers were able to connect it to an electrical circuit and measure the average signal from all of the cells in the antenna. The team then compared it to a typical human-made sensor by placing both at one end of a wind tunnel and wafting smells that both sensors would respond to: a floral scent and ethanol, a type of alcohol. The antenna reacted more quickly and took less time to recover between puffs.

To create Smellicopter, the team added the antenna sensor to an open-source drone platform that allows users to add special features. The researchers also added two plastic fins on the back of the drone to create drag to help it be constantly oriented upwind.

“From a robotics perspective, this is genius,” said co-author and co-advisor , a 91探花assistant professor of mechanical engineering. “The classic approach in robotics is to add more sensors, and maybe build a fancy algorithm or use machine learning to estimate wind direction. It turns out, all you need is to add a fin.”

Smellicopter doesn’t need any help from the researchers to search for odors. The team created a “cast and surge” protocol for the drone that mimics how moths search for smells. Smellicopter begins its search by moving to the left for a specific distance. If nothing passes a specific smell threshold, Smellicopter then moves to the right for the same distance. Once it detects an odor, it changes its flying pattern to surge toward it.

Smellicopter can also avoid obstacles with the help of four infrared sensors that let it measure what’s around it 10 times each second. When something comes within about eight inches (20 centimeters) of the drone, it changes direction by going to the next stage of its cast-and-surge protocol.

“So if Smellicopter was casting left and now there’s an obstacle on the left, it’ll switch to casting right,” Anderson said. “And if Smellicopter smells an odor but there’s an obstacle in front of it, it’s going to continue casting left or right until it’s able to surge forward when there’s not an obstacle in its path.”

Another advantage to Smellicopter is that it doesn’t need GPS, the team said. Instead it uses a camera to survey its surroundings, similar to how insects use their eyes. This makes Smellicopter well-suited for exploring indoor or underground spaces like mines or pipes.

During tests in the 91探花research lab, Smellicopter was naturally tuned to fly toward smells that moths find interesting, such as floral scents. But researchers hope that future work could have the moth antenna sense other smells, such as the exhaling of carbon dioxide from someone trapped under rubble or the chemical signature of an unexploded device.

“Finding plume sources is a perfect task for little robots like the Smellicopter and the ,” Fuller said. “Larger robots are capable of carrying an array of different sensors around and using them to build a map of their world. We can’t really do that at the small scale. But to find the source of a plume, all a robot really needs to do is avoid obstacles and stay in the plume while it moves upwind. It doesn’t need a sophisticated sensor suite for that 鈥� it just needs to be able to smell well. And that鈥檚 what the Smellicopter is really good at.”

, a 91探花electrical and computer engineering doctoral student, and , an electrical and computer engineering associate professor at the University of Maryland College Park, are also co-authors. This research was funded by , the Washington Research Foundation, the Joan and Richard Komen Endowed Chair and the Air Force Office of Scientific Research with .

For more information, contact Anderson at melaniea@uw.edu, Fuller at minster@uw.edu and Daniel at danielt@uw.edu.

Grant number: FA9550-14-1-0398

In the movie “Ant-Man,” the title character can shrink in size and travel by soaring on the back of an insect. Now researchers at the 91探花 have developed a tiny wireless steerable camera that can also ride aboard an insect, giving everyone a chance to see an Ant-Man view of the world.

The camera, which streams video to a smartphone at 1 to 5 frames per second, sits on a mechanical arm that can pivot 60 degrees. This allows a viewer to capture a high-resolution, panoramic shot or track a moving object while expending a minimal amount of energy. To demonstrate the versatility of this system, which weighs about 250 milligrams 鈥� about one-tenth the weight of a playing card 鈥� the team mounted it on top of live beetles and insect-sized robots.

The results July 15 in Science Robotics.

“We have created a low-power, low-weight, wireless camera system that can capture a first-person view of what’s happening from an actual live insect or create vision for small robots,” said senior author , a 91探花associate professor in the Paul G. Allen School of Computer Science & Engineering. “Vision is so important for communication and for navigation, but it’s extremely challenging to do it at such a small scale. As a result, prior to our work, wireless vision has not been possible for small robots or insects.”

Typical small cameras, such as those used in smartphones, use a lot of power to capture wide-angle, high-resolution photos, and that doesn’t work at the insect scale. While the cameras themselves are lightweight, the batteries they need to support them make the overall system too big and heavy for insects 鈥� or insect-sized robots 鈥� to lug around. So the team took a lesson from biology.

“Similar to cameras, vision in animals requires a lot of power,” said co-author , a 91探花assistant professor of mechanical engineering. “It’s less of a big deal in larger creatures like humans, but flies are using 10 to 20% of their resting energy just to power their brains, most of which is devoted to visual processing. To help cut the cost, some flies have a small, high-resolution region of their compound eyes. They turn their heads to steer where they want to see with extra clarity, such as for chasing prey or a mate. This saves power over having high resolution over their entire visual field.鈥�

To mimic an animal’s vision, the researchers used a tiny, ultra-low-power black-and-white camera that can sweep across a field of view with the help of a mechanical arm. The arm moves when the team applies a high voltage, which makes the material bend and move the camera to the desired position. Unless the team applies more power, the arm stays at that angle for about a minute before relaxing back to its original position. This is similar to how people can keep their head turned in one direction for only a short period of time before returning to a more neutral position.

“One advantage to being able to move the camera is that you can get a wide-angle view of what’s happening without consuming a huge amount of power,” said co-lead author , a 91探花doctoral student in electrical and computer engineering. “We can track a moving object without having to spend the energy to move a whole robot. These images are also at a higher resolution than if we used a wide-angle lens, which would create an image with the same number of pixels divided up over a much larger area.”

The camera and arm are controlled via Bluetooth from a smartphone from a distance up to 120 meters away, just a little longer than a football field.

The researchers attached their removable system to the backs of two different types of beetles 鈥� a death-feigning beetle and a Pinacate beetle. Similar beetles have been known to be able to carry loads heavier than half a gram, the researchers said.

“We made sure the beetles could still move properly when they were carrying our system,” said co-lead author , a 91探花doctoral student in electrical and computer engineering. “They were able to navigate freely across gravel, up a slope and even climb trees.”

The beetles also lived for at least a year after the experiment ended.

“We added a small accelerometer to our system to be able to detect when the beetle moves. Then it only captures images during that time,” Iyer said. “If the camera is just continuously streaming without this accelerometer, we could record one to two hours before the battery died. With the accelerometer, we could record for six hours or more, depending on the beetle’s activity level.”

The researchers also used their camera system to design the world鈥檚 smallest terrestrial, power-autonomous robot with wireless vision. This insect-sized robot uses vibrations to move and consumes almost the same power as low-power Bluetooth radios need to operate.

The team found, however, that the vibrations shook the camera and produced distorted images. The researchers solved this issue by having the robot stop momentarily, take a picture and then resume its journey. With this strategy, the system was still able to move about 2 to 3 centimeters per second 鈥� faster than any other tiny robot that uses vibrations to move 鈥� and had a battery life of about 90 minutes.

While the team is excited about the potential for lightweight and low-power mobile cameras, the researchers acknowledge that this technology comes with a new set of privacy risks.

“As researchers we strongly believe that it’s really important to put things in the public domain so people are aware of the risks and so people can start coming up with solutions to address them,” Gollakota said.

Applications could range from biology to exploring novel environments, the researchers said. The team hopes that future versions of the camera will require even less power and be battery free, potentially solar-powered.

“This is the first time that we’ve had a first-person view from the back of a beetle while it’s walking around. There are so many questions you could explore, such as how does the beetle respond to different stimuli that it sees in the environment?” Iyer said. “But also, insects can traverse rocky environments, which is really challenging for robots to do at this scale. So this system can also help us out by letting us see or collect samples from hard-to-navigate spaces.”

, a 91探花mechanical engineering doctoral student, is also a co-author on this paper. This research was funded by a Microsoft fellowship and the National Science Foundation.

For more information, contact insectcam@cs.washington.edu.

Farmers can already use drones to soar over huge fields and monitor temperature, humidity or crop health. But these machines need so much power to fly that they can’t get very far without needing a charge.

Now, engineers at the 91探花 have created a sensing system that is small enough to ride aboard a bumblebee. Because insects can fly on their own, the package requires only a tiny rechargeable battery that could last for seven hours of flight and then charge while the bees are in their hive at night. The research team will聽 Dec. 11 and in person at the .

“Drones can fly for maybe 10 or 20 minutes before they need to charge again, whereas our bees can collect data for hours,” said senior author , an associate professor in the UW’s Paul G. Allen School of Computer Science & Engineering. “We showed for the first time that it’s possible to actually do all this computation and sensing using insects in lieu of drones.”

While using insects instead of drones solves the power problem, this technique has its own set of complications: First, insects can’t carry much weight. And second, GPS receivers, which work well for helping drones report their positions, consume too much power for this application. To develop a sensor package that could fit on an insect and sense its location, the team had to address both issues.

“We decided to use bumblebees because they’re large enough to carry a tiny battery that can power our system, and they return to a hive every night where we could wirelessly recharge the batteries,” said co-author , a doctoral student in the 91探花Department of Electrical & Computer Engineering. “For this research we followed the best methods for care and handling of these creatures.”

Previously other research groups have by supergluing small trackers, like radio-frequency identification, or RFID, tags, to them to follow their movement. For these types of experiments, researchers put a bee in the freezer for a few minutes to slow it down before they glue on the backpack. When they’re finished with the experiment, the team removes the backpack through a similar process.

These prior studies, however, only involved backpacks that simply tracked bees’ locations over short distances 鈥� around 10 inches 鈥� and did not carry anything to survey the environment around the insects. Here, Gollakota, Iyer and their group designed a sensor backpack that rides on the bees’ backs and weighs 102 milligrams, or about the weight of .

“The rechargeable battery powering the backpack weighs about 70 milligrams, so we had a little over 30 milligrams left for everything else, like the sensors and the localization system to track the insect’s position,” said co-author , a doctoral student in the Allen School.

Because bees don’t advertise where they are flying and because GPS receivers are too power-hungry to ride on a tiny insect, the team came up with a method that uses no power to localize the bees. The researchers set up multiple antennas that broadcasted signals from a base station across a specific area. A receiver in a bee’s backpack uses the strength of the signal and the angle difference between the bee and the base station to triangulate the insect’s position.

“To test the localization system, we did an experiment on a soccer field,” said co-author , a doctoral student in the Allen School. “We set up our base station with four antennas on one side of the field, and then we had a bee with a backpack flying around in a jar that we moved away from the antennas. We were able to detect the bee’s position as long as it was within 80 meters, about three-quarters the length of a football field, of the antennas.”

Next the team added a series of small sensors 鈥� monitoring temperature, humidity and light intensity 鈥� to the backpack. That way, the bees could collect data and log that information along with their location, and eventually compile information about a whole farm.

“It would be interesting to see if the bees prefer one region of the farm and visit other areas less often,” said co-author , an assistant professor in the 91探花Department of Mechanical Engineering. “Alternatively, if you want to know what’s happening in a particular area, you could also program the backpack to say: ‘Hey bees, if you visit this location, take a temperature reading.'”

Then after the bees have finished their day of foraging, they return to their hive where the backpack can upload any data it collected via a method called , through which a device can share information by reflecting radio waves transmitted from a nearby antenna.

Right now the backpacks can only store about 30 kilobytes of data, so they are limited to carrying sensors that create small amounts of data. Also, the backpacks can upload data only when the bees return to the hive. The team would eventually like to develop backpacks with cameras that can livestream information about plant health back to farmers.

“Having insects carry these sensor systems could be beneficial for farms because bees can sense things that electronic objects, like drones, cannot,” Gollakota said. “With a drone, you’re just flying around randomly, while a bee is going to be drawn to specific things, like the plants it prefers to pollinate. And on top of learning about the environment, you can also learn a lot about how the bees behave.”

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For more information, contact the research team at livingiot@cs.washington.edu.

Insect-sized flying robots could help with time-consuming tasks like surveying crop growth on large farms or sniffing out gas leaks. These robots soar by fluttering tiny wings because they are too small to use propellers, like those seen on their larger drone cousins. Small size is advantageous: These robots are cheap to make and can easily slip into tight places that are inaccessible to big drones.

But current flying robo-insects are still tethered to the ground. The electronics they need to power and control their wings are too heavy for these miniature robots to carry.

Now, engineers at the 91探花 have for the first time cut the cord and added a brain, allowing their RoboFly to take its first independent flaps. This might be one small flap for a robot, but it’s one giant leap for robot-kind. The team will present its findings May 23 at the in Brisbane, Australia.

RoboFly is slightly heavier than a toothpick and is powered by a laser beam. It uses a tiny onboard circuit that converts the laser energy into enough electricity to operate its wings.

“Before now, the concept of wireless insect-sized flying robots was science fiction. Would we ever be able to make them work without needing a wire?” said co-author , an assistant professor in the 91探花Department of Mechanical Engineering. “Our new wireless RoboFly shows they’re much closer to real life.”

The engineering challenge is the flapping. Wing flapping is a power-hungry process, and both the power source and the controller that directs the wings are too big and bulky to ride aboard a tiny robot. So Fuller’s previous robo-insect, the , had a leash 鈥� it received power and control through wires from the ground.

But a flying robot should be able to operate on its own. Fuller and team decided to use a narrow invisible laser beam to power their robot. They pointed the laser beam at a photovoltaic cell, which is attached above RoboFly and converts the laser light into electricity.

“It was the most efficient way to quickly transmit a lot of power to RoboFly without adding much weight,” said co-author , an associate professor in the UW’s Paul G. Allen School of Computer Science & Engineering.

Still, the laser alone does not provide enough voltage to move the wings. That’s why the team designed a circuit that boosted the seven volts coming out of the photovoltaic cell up to the 240 volts needed for flight.

To give RoboFly control over its own wings, the engineers provided a brain: They added a microcontroller to the same circuit.

“The microcontroller acts like a real fly’s brain telling wing muscles when to fire,” said co-author , a doctoral student in the 91探花Department of Electrical Engineering. “On RoboFly, it tells the wings things like ‘flap hard now’ or ‘don’t flap.'”

Specifically, the controller sends voltage in waves to mimic the fluttering of a real insect’s wings.

“It uses pulses to shape the wave,” said , the lead author and a mechanical engineering doctoral student. “To make the wings flap forward swiftly, it sends a series of pulses in rapid succession and then slows the pulsing down as you get near the top of the wave. And then it does this in reverse to make the wings flap smoothly in the other direction.”

For now, RoboFly can only take off and land. Once its photovoltaic cell is out of the direct line of sight of the laser, the robot runs out of power and lands. But the team hopes to soon be able to steer the laser so that RoboFly can hover and fly around.

While RoboFly is currently powered by a laser beam, future versions could use tiny batteries or harvest energy from radio frequency signals, Gollakota said. That way, their power source can be modified for specific tasks.

Future RoboFlies can also look forward to more advanced brains and sensor systems that help the robots navigate and complete tasks on their own, Fuller said.

“I’d really like to make one that finds methane leaks,” he said. “You could buy a suitcase full of them, open it up, and they would fly around your building looking for plumes of gas coming out of leaky pipes. If these robots can make it easy to find leaks, they will be much more likely to be patched up, which will reduce greenhouse emissions. This is inspired by real flies, which are really good at flying around looking for smelly things. So we think this is a good application for our RoboFly.”

Mechanical engineering doctoral student is also a co-author on this paper. This research was funded by the 91探花 and a Microsoft student fellowship.

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For more information, contact the research team at wireless_fly@uw.edu.

Small drones need to stay aloft do their jobs 鈥� whether that’s searching for dangerous gas leaks or remotely monitoring atmospheric conditions. But this effort can quickly drain battery-powered energy.

A team of Harvard roboticists and a 91探花 mechanical engineer have demonstrated that their insect-sized flying robots, nicknamed the RoboBees, can now perch during flight to save energy 鈥� like bats, birds or butterflies.

In a paper published in on May 19, they describe a switchable electroadhesive that enables a flying robotic insect to perch on materials such glass, wood or a leaf. This requires roughly 1,000 times less power than sustained flight.

“One of the biggest difficulties with building insect-sized robots is that the physics change as you go that small. A lot of technologies that have been deployed successfully on larger robots become impractical on a centimeter-sized robot,” said co-author , 91探花assistant professor of mechanical engineering. “We take inspiration from flying insects because they’ve already found solutions for these challenges.”

https://www.youtube.com/watch?v=gI7yE01G0oQ

Video Credit: Science/AAAS

A swarm of insect-sized flying robots equipped with sensors could collect detailed information about air pollution, Fuller said, including searching for methane leaks that are a significant source of greenhouse gas pollution. But that will require energy-saving solutions that extend current flight times.

鈥淢any applications for small drones require them to stay in the air for extended periods,鈥� said Moritz Graule, first author of the paper who conducted this research as a student at the Harvard John A. Paulson School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering. 鈥淯nfortunately, smaller drones run out of energy quickly. We want to keep them aloft longer without requiring too much additional energy.鈥�

Mechanisms that animals use to perch, such as sticky adhesives or talons, aren’t easily adaptable to a paper clip-size microrobot.聽 So the team turned to electrostatic adhesion聽鈥� the same basic science that causes a static-charged sock to cling to a pants leg or a balloon to stick to a wall.

The RoboBee, pioneered at the Harvard Microrobotics Lab, uses an electrode patch and a foam mount that absorbs shock. The entire mechanism weighs 13.4 mg, bringing the total weight of the robot to about 100mg 鈥� similar to the weight of a real honeybee. The robot takes off and flies normally. When the electrode patch is supplied with a charge, it can stick to almost any surface, from glass to wood to a leaf. To detach, the power supply is simply switched off.

The patch requires about 1,000 times less power to perch than it does to hover, which can dramatically extend the operation life of the robot.

鈥淲hen making robots the size of insects, simplicity and low power are always key constraints,” said Robert Wood, Charles River Professor of Engineering and Applied Sciences at SEAS and聽core faculty member of the the Wyss Institute, and senior author of the study.

Fuller, who led the RoboBees flight experiments as a postdoctoral scholar at Harvard, joined the 91探花Mechanical Engineering Department in 2015. He will continue his research as part of (NIFTI) housed at the UW.

He joins an interdisciplinary team of 91探花researchers working on that can be applied to small, unmanned or remotely operated aircraft.

“One of the things I’m focusing on is how we can start giving these insect-sized robots the ability to perceive the world and control their own flight,” Fuller said.

“Right now the robot relies on an external array of cameras and computers to fly,” he said. “That proves that we have the necessary fabrication technology in place, but we鈥檇 like to eliminate the external cameras. With sensors onboard, the robot will be able do things like stabilize its flight, locate suitable landing sites, or follow the source of an odor plume. “

The Science paper was coauthored by Pakpong Chirarattananon, Noah Jafferis, Matthew Spenko and Roy Kornbluh. The research was funded by the National Science Foundation, the Wyss Institute for Biologically Inspired Engineering, and the Swiss Study Foundation.

For more information, contact Fuller at minster@uw.edu.

To receive copies of the paper and image/video permissions, please contact the Science press package team at 202-326-6440 or scipak@aaas.org.

This was adapted from a Harvard University release.