Tag Archives: drone

#439941 Flexible Monocopter Drone Can Be ...

It turns out that you don't need a lot of hardware to make a flying robot. Flying robots are usually way, way, way over-engineered, with ridiculously over the top components like two whole wings or an obviously ludicrous four separate motors. Maybe that kind of stuff works for people with more funding than they know what to do with, but for anyone trying to keep to a reasonable budget, all it actually takes to make a flying robot is one single airfoil plus an attached fixed-pitch propeller. And if you make that airfoil flexible, you can even fold the entire thing up into a sort of flying robotic swiss roll.
This type of drone is called a monocopter, and the design is very generally based on samara seeds, which are those single-wing seed pods that spin down from maple trees. The ability to spin slows the seeds' descent to the ground, allowing them to spread farther from the tree. It's an inherently stable design, meaning that it'll spin all by itself and do so in a stable and predictable way, which is a nice feature for a drone to have—if everything completely dies, it'll just spin itself gently down to a landing by default.

The monocopter we're looking at here, called F-SAM, comes from the Singapore University of Technology & Design, and we've written about some of their flying robots in the past, including this transformable hovering rotorcraft. F-SAM stands for Foldable Single Actuator Monocopter, and as you might expect, it's a monocopter that can fold up and uses just one single actuator for control.

There may not be a lot going on here hardware-wise, but that's part of the charm of this design. The one actuator gives complete directional control: increasing the throttle increases the RPM of the aircraft, causing it to gain altitude, which is pretty straightforward. Directional control is trickier, but not much trickier, requiring repetitive pulsing of the motor at a point during the aircraft's spin when it's pointed in the direction you want it to go. F-SAM is operating in a motion-capture environment in the video to explore its potential for precision autonomy, but it's not restricted to that environment, and doesn't require external sensing for control.

While F-SAM's control board was custom designed and the wing requires some fabrication, the rest of the parts are cheap and off the shelf. The total weight of F-SAM is just 69g, of which nearly 40% is battery, yielding a flight time of about 16 minutes. If you look closely, you'll also see a teeny little carbon fiber leg of sorts that keeps the prop up above the ground, enabling the ground takeoff behavior without contacting the ground.
You can find the entire F-SAM paper open access here, but we also asked the authors a couple of extra questions.
IEEE Spectrum: It looks like you explored different materials and combinations of materials for the flexible wing structure. Why did you end up with this mix of balsa wood and plastic?

Shane Kyi Hla Win: The wing structure of a monocopter requires rigidity in order to be controllable in flight. Although it is possible for the monocopter to fly with more flexible materials we tested, such as flexible plastic or polymide flex, they allow the wing to twist freely mid-flight making cyclic control effort from the motor less effective. The balsa laminated with plastic provides enough rigidity for an effective control, while allowing folding in a pre-determined triangular fold.
Can F-SAM fly outdoors? What is required to fly it outside of a motion capture environment?
Yes it can fly outdoors. It is passively stable so it does not require a closed-loop control for its flight. The motion capture environment provides its absolute position for station-holding and waypoint flights when indoors. For outdoor flight, an electronic compass provides the relative heading for the basic cyclic control. We are working on a prototype with an integrated GPS for outdoor autonomous flights.
Would you be able to add a camera or other sensors to F-SAM?
A camera can be added (we have done this before), but due to its spinning nature, images captured can come out blurry. 360 cameras are becoming lighter and smaller and we may try putting one on F-SAM or other monocopters we have. Other possible sensors to include are LiDAR sensor or ToF sensor. With LiDAR, the platform has an advantage as it is already spinning at a known RPM. A conventional LiDAR system requires a dedicated actuator to create a spinning motion. As a rotating platform, F-SAM already possesses the natural spinning dynamics, hence making LiDAR integration lightweight and more efficient.
Your paper says that “in the future, we may look into possible launching of F-SAM directly from the container, without the need for human intervention.” Can you describe how this would happen?
Currently, F-SAM can be folded into a compact form and stored inside a container. However, it still requires a human to unfold it and either hand-launch it or put it on the floor to fly off. In the future, we envision that F-SAM is put inside a container which has the mechanism (such as pressured gas) to catapult the folded unit into the air, which can begin unfolding immediately due to elastic materials used. The motor can initiate the spin which allows the wing to straighten out due to centrifugal forces.
Do you think F-SAM would make a good consumer drone?
F-SAM could be a good toy but it may not be a good alternative to quadcopters if the objective is conventional aerial photography or videography. However, it can be a good contender for single-use GPS-guided reconnaissance missions. As it uses only one actuator for its flight, it can be made relatively cheaply. It is also very silent during its flight and easily camouflaged once landed. Various lightweight sensors can be integrated onto the platform for different types of missions, such as climate monitoring. F-SAM units can be deployed from the air, as they can also autorotate on their way down, while also flying at certain periods for extended meteorological data collection in the air.
What are you working on next?
We have a few exciting projects on hand, most of which focus on 'do more with less' theme. This means our projects aim to achieve multiple missions and flight modes while using as few actuators as possible. Like F-SAM which uses only one actuator to achieve controllable flight, another project we are working on is the fully autorotating version, named Samara Autorotating Wing (SAW). This platform, published earlier this year in IEEE Transactions on Robotics , is able to achieve two flight modes (autorotation and diving) with just one actuator. It is ideal for deploying single-use sensors to remote locations. For example, we can use the platform to deploy sensors for forest monitoring or wildfire alert system. The sensors can land on tree canopies, and once landed the wing provides the necessary area for capturing solar energy for persistent operation over several years. Another interesting scenario is using the autorotating platform to guide the radiosondes back to the collection point once its journey upwards is completed. Currently, many radiosondes are sent up with hydrogen balloons from weather stations all across the world (more than 20,000 annually from Australia alone) and once the balloon reaches a high altitude and bursts, the sensors drop back onto the earth and no effort is spent to retrieve these sensors. By guiding these sensors back to a collection point, millions of dollars can be saved every year—and also [it helps] save the environment by polluting less. Continue reading

Posted in Human Robots

#439816 This Bipedal Drone Robot Can Walk, Fly, ...

Most animals are limited to either walking, flying, or swimming, with a handful of lucky species whose physiology allows them to cross over. A new robot took inspiration from them, and can fly like a bird just as well as it can walk like a (weirdly awkward, metallic, tiny) person. It also happens to be able to skateboard and slackline, two skills most humans will never pick up.

Described in a paper published this week in Science Robotics, the robot’s name is Leo, which is short for Leonardo, which is short for LEgs ONboARD drOne. The name makes it sound like a drone with legs, but it has a somewhat humanoid shape, with multi-joint legs, propeller thrusters that look like arms, a “body” that contains its motors and electronics, and a dome-shaped protection helmet.

Leo was built by a team at Caltech, and they were particularly interested in how the robot would transition between walking and flying. The team notes that they studied the way birds use their legs to generate thrust when they take off, and applied similar principles to the robot. In a video that shows Leo approaching a staircase, taking off, and gliding over the stairs to land near the bottom, the robot’s motions are seamlessly graceful.

“There is a similarity between how a human wearing a jet suit controls their legs and feet when landing or taking off and how LEO uses synchronized control of distributed propeller-based thrusters and leg joints,” said Soon-Jo Chung, one of the paper’s authors a professor at Caltech. “We wanted to study the interface of walking and flying from the dynamics and control standpoint.”

Leo walks at a speed of 20 centimeters (7.87 inches) per second, but can move faster by mixing in some flying with the walking. How wide our steps are, where we place our feet, and where our torsos are in relation to our legs all help us balance when we walk. The robot uses its propellers to help it balance, while its leg actuators move it forward.

To teach the robot to slackline—which is much harder than walking on a balance beam—the team overrode its feet contact sensors with a fixed virtual foot contact centered just underneath it, because the sensors weren’t able to detect the line. The propellers played a big part as well, helping keep Leo upright and balanced.

For the robot to ride a skateboard, the team broke the process down into two distinct components: controlling the steering angle and controlling the skateboard’s acceleration and deceleration. Placing Leo’s legs in specific spots on the board made it tilt to enable steering, and forward acceleration was achieved by moving the bot’s center of mass backward while pitching the body forward at the same time.

So besides being cool (and a little creepy), what’s the goal of developing a robot like Leo? The paper authors see robots like Leo enabling a range of robotic missions that couldn’t be carried out by ground or aerial robots.

“Perhaps the most well-suited applications for Leo would be the ones that involve physical interactions with structures at a high altitude, which are usually dangerous for human workers and call for a substitution by robotic workers,” the paper’s authors said. Examples could include high-voltage line inspection, painting tall bridges or other high-up surfaces, inspecting building roofs or oil refinery pipes, or landing sensitive equipment on an extraterrestrial object.

Next up for Leo is an upgrade to its performance via a more rigid leg design, which will help support the robot’s weight and increase the thrust force of its propellers. The team also wants to make Leo more autonomous, and plans to add a drone landing control algorithm to its software, ultimately aiming for the robot to be able to decide where and when to walk versus fly.

Leo hasn’t quite achieved the wow factor of Boston Dynamics’ dancing robots (or its Atlas that can do parkour), but it’s on its way.

Image Credit: Caltech Center for Autonomous Systems and Technologies/Science Robotics Continue reading

Posted in Human Robots

#439551 Video Friday: Drone Refueling

Video Friday is your weekly selection of awesome robotics videos, collected by your Automaton bloggers. We’ll also be posting a weekly calendar of upcoming robotics events for the next few months; here's what we have so far (send us your events!):

RoboCup 2021 – June 22-28, 2021 – [Online Event]
RSS 2021 – July 12-16, 2021 – [Online Event]
Humanoids 2020 – July 19-21, 2021 – [Online Event]
RO-MAN 2021 – August 8-12, 2021 – [Online Event]
DARPA SubT Finals – September 21-23, 2021 – Louisville, KY, USA
WeRobot 2021 – September 23-25, 2021 – Coral Gables, FL, USA
IROS 2021 – September 27-1, 2021 – [Online Event]
ROSCon 2021 – October 21-23, 2021 – New Orleans, LA, USA
Let us know if you have suggestions for next week, and enjoy today's videos.

The MQ-25 T1 test asset has flown into the history books as the first unmanned aircraft to ever refuel another aircraft—piloted or autonomous—during flight.

[ Boeing ]

WomBot is an exploratory robot for monitoring wombat burrows, and the press release for it included this rather disappointing video of WomBot discovering a wombat in its burrow.

Apparently that’s what the butt of a dirt-covered wombat looks like. Here is a much more exciting video of an entirely different wombat burrow exploring robot where you get the wombat payoff that you deserve:

[ Paper ]

During the dark of night, using LiDAR for eyes, Cassie Blue is operating fully autonomously on the University of Michigan Wave Field. The terrain is challenging and was not pre-mapped.

For more on what they've been up to over at the University of Michigan, here’s a talk from them at the ICRA 2021 Workshop on Legged Robots.

[ Michigan Robotics ]

Thanks, Jessy!

The new Genesis LiveDrive LDD 1800 Series is a new high-torque direct-drive actuator. No gearbox!

[ Genesis ]

This Counter-Unmanned Air System (C-UAS) from DARPA’s Mobile Force Protection (MFP) program may look like it shot out a net and missed, but it was actually firing a bunch of sticky streamers that tangle up motors and whatnot. Festive and crashy!

[ Genesis ]

Learn about this year’s Kuka Innovation Award from some of the teams and judges, some of whom need a haircut more badly than others.

[ KUKA ]

20th Century Studios and Locksmith Animation’s “Ron’s Gone Wrong” is the story of Barney, a socially awkward middle-schooler and Ron, his new walking, talking, digitally-connected device, which is supposed to be his “Best Friend out of the Box.”

For a robot unboxing, that’s actually pretty good. Like, it arrives with a charged battery!

[ EW ]

The robot will serve you now! And it will do so without making a huge mess, thanks to folks from the University of Naples Federico II in Italy.

[ Paper ]

Thanks, Mario!

Over the past year ABB has committed to supporting diversity and inclusion amongst all of our team members, partners and suppliers. To kick off our celebration of Pride Month, Yumi put on the pride flag to show ABB’s commitment to the LGBTQ+ community.

[ ABB ]

How it’s made: surgical masks.

[ Genik ]

Meet Hera, our very own asteroid detective. Together with two CubeSats—Milani the rock decoder and Juventas the radar visionary—Hera is off on an adventure to explore Didymos, a double asteroid system that is typical of the thousands that pose an impact risk to planet Earth.

[ ESA ]

The goal of the EU-funded project ADIR was to demonstrate the feasibility of a key technology for next generation urban mining. Specifically, the project investigated the automated disassembly of electronic equipment to separate and recover valuable materials.

[ ADIR ]

NASA’s Resilient Autonomy activity is developing autonomous software for potential use in aircraft ranging from general aviation retrofit to future autonomous aircraft. This simulator footage shows iGCAS, or improved GCAS, save a small aircraft from diving into a canyon, into the side of a mountain, or into the ground.

[ NASA ]

Mess with the Cocobo security robot at your peril.

[ Impress ]

I thought the whole point of growing rice in flooded fields was that you avoided weed problems, but I guess there are enough semi-aquatic weeds that it can be handy to have a little robot boat that drives around stirring up mud to surpress weed growth.

[ Robotstart ]

We present experimental work on traversing steep, granular slopes with the dynamically walking quadrupedal robot SpaceBok. We validate static and dynamic locomotion with two different foot types (point foot and passive-adaptive planar foot) on Mars analog slopes of up to 25°(the maximum of the testbed).

[ Paper ]

You'll have to suffer through a little bit of German for this one, but you'll be rewarded with a pretty slick flying wing at the end.

[ BFW ]

Thanks, Fan!

Have you ever wondered whether the individual success metrics prevalent in robotics create perverse incentives that harm the long-term needs of the field? Or if the development of high-stakes autonomous systems warrants taking significant risks with real-world deployment to accelerate progress? Are the standards for experimental validation insufficient to ensure that published robotics methods work in the real world? We have all the answers!

[ Robotics Debates ] Continue reading

Posted in Human Robots

#439447 Nothing Can Keep This Drone Down

When life knocks you down, you’ve got to get back up. Ladybugs take this advice seriously in the most literal sense. If caught on their backs, the insects are able to use their tough exterior wings, called elytra (of late made famous in the game Minecraft), to self-right themselves in just a fraction of a second.

Inspired by this approach, researchers have created self-righting drones with artificial elytra. Simulations and experiments show that the artificial elytra can not only help salvage fixed-wing drones from compromising positions, but also improve the aerodynamics of the vehicles during flight. The results are described in a study published July 9 in IEEE Robotics and Automation Letters.

Charalampos Vourtsis is a doctoral assistant at the Laboratory of Intelligent Systems, Ecole Polytechnique Federale de Lausanne in Switzerland who co-created the new design. He notes that beetles, including ladybugs, have existed for tens of millions of years. “Over that time, they have developed several survival mechanisms that we found to be a source of inspiration for applications in modern robotics,” he says.

His team was particularly intrigued by beetles’ elytra, which for ladybugs are their famous black-spotted, red exterior wing. Underneath the elytra is the hind wing, the semi-transparent appendage that’s actually used for flight.

When stuck on their backs, ladybugs use their elytra to stabilize themselves, and then thrust their legs or hind wings in order to pitch over and self-right. Vourtsis’ team designed Micro Aerial Vehicles (MAVs) that use a similar technique, but with actuators to provide the self-righting force. “Similar to the insect, the artificial elytra feature degrees of freedom that allow them to reorient the vehicle if it flips over or lands upside down,” explains Vourtsis.

The researchers created and tested artificial elytra of different lengths (11, 14 and 17 centimeters) and torques to determine the most effective combination for self-righting a fixed-wing drone. While torque had little impact on performance, the length of elytra was found to be influential.

On a flat, hard surface, the shorter elytra lengths yielded mixed results. However, the longer length was associated with a perfect success rate. The longer elytra were then tested on different inclines of 10°, 20° and 30°, and at different orientations. The drones used the elytra to self-right themselves in all scenarios, except for one position at the steepest incline.

The design was also tested on seven different terrains: pavement, course sand, fine sand, rocks, shells, wood chips and grass. The drones were able to self-right with a perfect success rate across all terrains, with the exception of grass and fine sand. Vourtsis notes that the current design was made from widely available materials and a simple scale model of the beetle’s elytra—but further optimization may help the drones self-right on these more difficult terrains.

As an added bonus, the elytra were found to add non-negligible lift during flight, which offsets their weight.

Vourtsis says his team hopes to benefit from other design features of the beetles’ elytra. “We are currently investigating elytra for protecting folding wings when the drone moves on the ground among bushes, stones, and other obstacles, just like beetles do,” explains Vourtsis. “That would enable drones to fly long distances with large, unfolded wings, and safely land and locomote in a compact format in narrow spaces.” Continue reading

Posted in Human Robots

#439432 Nothing Can Keep This Drone Down

When life knocks you down, you’ve got to get back up. Ladybugs take this advice seriously in the most literal sense. If caught on their backs, the insects are able to use their tough exterior wings, called elytra (of late made famous in the game Minecraft), to self-right themselves in just a fraction of a second.

Inspired by this approach, researchers have created self-righting drones with artificial elytra. Simulations and experiments show that the artificial elytra can not only help salvage fixed-wing drones from compromising positions, but also improve the aerodynamics of the vehicles during flight. The results are described in a study published July 9 in IEEE Robotics and Automation Letters.

Charalampos Vourtsis is a doctoral assistant at the Laboratory of Intelligent Systems, Ecole Polytechnique Federale de Lausanne in Switzerland who co-created the new design. He notes that beetles, including ladybugs, have existed for tens of millions of years. “Over that time, they have developed several survival mechanisms that we found to be a source of inspiration for applications in modern robotics,” he says.

His team was particularly intrigued by beetles’ elytra, which for ladybugs are their famous black-spotted, red exterior wing. Underneath the elytra is the hind wing, the semi-transparent appendage that’s actually used for flight.

When stuck on their backs, ladybugs use their elytra to stabilize themselves, and then thrust their legs or hind wings in order to pitch over and self-right. Vourtsis’ team designed Micro Aerial Vehicles (MAVs) that use a similar technique, but with actuators to provide the self-righting force. “Similar to the insect, the artificial elytra feature degrees of freedom that allow them to reorient the vehicle if it flips over or lands upside down,” explains Vourtsis.

The researchers created and tested artificial elytra of different lengths (11, 14 and 17 centimeters) and torques to determine the most effective combination for self-righting a fixed-wing drone. While torque had little impact on performance, the length of elytra was found to be influential.

On a flat, hard surface, the shorter elytra lengths yielded mixed results. However, the longer length was associated with a perfect success rate. The longer elytra were then tested on different inclines of 10°, 20° and 30°, and at different orientations. The drones used the elytra to self-right themselves in all scenarios, except for one position at the steepest incline.

The design was also tested on seven different terrains: pavement, course sand, fine sand, rocks, shells, wood chips and grass. The drones were able to self-right with a perfect success rate across all terrains, with the exception of grass and fine sand. Vourtsis notes that the current design was made from widely available materials and a simple scale model of the beetle’s elytra—but further optimization may help the drones self-right on these more difficult terrains.

As an added bonus, the elytra were found to add non-negligible lift during flight, which offsets their weight.

Vourtsis says his team hopes to benefit from other design features of the beetles’ elytra. “We are currently investigating elytra for protecting folding wings when the drone moves on the ground among bushes, stones, and other obstacles, just like beetles do,” explains Vourtsis. “That would enable drones to fly long distances with large, unfolded wings, and safely land and locomote in a compact format in narrow spaces.” Continue reading

Posted in Human Robots