High-Speed Drones Use AI To Spoil The Fun

November 29, 2017 by Dan Maloney 17 Comments

Some people look forward to the day when robots have taken over all our jobs and given us an economy where we can while our days away on leisure activities. But if your idea of play is drone racing, you may be out of luck if this AI pilot for high-speed racing drones has anything to say about it.

NASA’s Jet Propulsion Lab has been working for the past two years to develop the algorithms needed to let high-performance UAVs navigate typical drone racing obstacles, and from the look of the tests in the video below, they’ve made a lot of progress. The system is vision based, with the AI drones equipped with wide-field cameras looking both forward and down. The indoor test course has seemingly random floor tiles scattered around, which we guess provide some kind of waypoints for the drones. A previous video details a little about the architecture, and it seems the drones are doing the computer vision on-board, which we find pretty impressive.

Despite the program being bankrolled by Google, we’re sure no evil will come of this, and that we’ll be in no danger of being chased down by swarms of high-speed flying killbots anytime soon. For now we can take solace in the fact that JPL’s algorithms still can’t beat an elite human pilot like [Ken Loo], who bested the bots overall. But alarmingly, the human did no better than the bots on his first lap, which suggests that once the AI gets a little creativity and intuition like that needed to best a Go champion, [Ken] might need to find another line of work.

Continue reading “High-Speed Drones Use AI To Spoil The Fun” →

Russian Drone Can Lift 142 Phantom 3 Drones

November 28, 2017 by Will Sweatman 58 Comments

Russia has long been known for making large machines. They hold the current record for the largest helicopter ever made – the MiL V12. Same goes for the world’s largest airplane, the Antonov An-225. Largest submarine? Yep, they made that too – the Typhoon class. It would appear they’ve thrown their hat in the drone business as well.

While the SKYF drone is made by a private Russian company, it is one of the largest drones we’ve ever seen. Able to lift 400 pounds (a Phantom 3 weighs 2.8 pounds) and can fly for eight hours, the SKYF drone is a nice piece of aeronautical engineering. Quad-copter style drones provide lift by brute force, and are typically plagued with low lift capacities and short flight times. The SKYF triumphs over these limitations by using gasoline powered engines for lift and electric motors for navigation.

It’s still in the prototype stage and being advertised for use in natural disasters and the agriculture industry. Check out the video in the link above to see the SKYF in action.

What’s the largest drone you’ve seen?

Thanks to [Itay] for the tip!

Acetone Smoothing Results In Working Motor

November 20, 2017 by Brian Benchoff 20 Comments

Here’s something only ’90s kids will remember. In 1998, the Air Hogs Sky Shark, a free-flying model airplane powered by compressed air was released. This plane featured foam stabilizers, wings, a molded fuselage that served as a reservoir, and a novel engine powered by compressed air. The complete Sky Shark setup included an air pump. All you had to do was plug the plane into the pump, try to break the pressure gauge, and let the plane fly off into a tree or a neighbor’s rooftop. It’s still a relatively interesting mechanism, and although we’re not going to see compressed air drones anytime soon it’s still a cool toy.

Since [Tom Stanton] is working at the intersection of small-scale aeronautics and 3D printing, he thought he would take a swing at building his own 3D printed air motor. This is an interesting challenge — the engine needs to be air-tight, and it needs to produce some sort of usable power. Is a standard printer up to the task? Somewhat surprisingly, yes.

The design of [Tom]’s motor is more or less the same as what is found in the Air Hogs motor from twenty years ago. A piston is attached to a crank, which is attached to a flywheel, in this case a propeller. Above the cylinder, a ball valve keeps the air from rushing in. A spring is mounted to the top of the piston which pushes the ball out of the way, allowing air into the cylinder. At the bottom of the stroke, the ball closes the valve and air escapes out of the bottom of the cylinder. Simple stuff, really, but can it be printed?

Instead of the usual printer [Tom] uses for his builds, he pulled out an old delta slightly modified for higher quality prints. Really, this is just a 0.2 mm nozzle and a few tweaks to the print settings, but the air motor [Tom] designed came out pretty well and was smoothed to a fine finish with acetone.

After assembling the motor, [Tom] hooked it up to a soda bottle serving as a compressed air reservoir. The motor worked, although it’s doubtful a plane powered with this motor would fly for very long. You can check out [Tom]’s video below.

Continue reading “Acetone Smoothing Results In Working Motor” →

3D Printed Hovercraft Takes To The Air

November 6, 2017 by John Baichtal 15 Comments

Instructables user [John_Hagy] and some classmates built an RC hovercraft as their final project in the Robotics Education Lab at NC State University. It’s a foam slab with a Hovership H2204X 2300Kv brushless motor inflating a skirt made out of ripstop nylon. Nylon is great here because it has a low friction coefficient and is nonporous to keep the air in. A second motor propels the craft, with a servo turning the whole motor assembly to steer. The team designed and 3D-printed fan holders which also help channel the air to where it’s supposed to go. Control is via a typical radio-control transmitter and receiver combo.

The project writeup includes a lot of fun detail like previous versions of the hovercraft as well as the research they undertook to learn how to configure the craft — clearly it’s their final paper put on the internet, and well done guys.

Needless to say, we at Hackaday can’t get enough of this sort of thing, as evidenced by this cool-looking hovercraft, this hovercraft made on a budget and this solar-powered ‘craft.

Hyperspectral Imaging – Seeing The Unseeable

October 25, 2017 by Will Sweatman 25 Comments

They say that a picture is worth a thousand words. But what is a picture exactly? One definition would be a perfect reflection of what we see, like one taken with a basic camera. Our view of the natural world is constrained to a bandwidth of 400 to 700 nanometers within the electromagnetic spectrum, so our cameras produce images within this same bandwidth.

For example, if I take a picture of a yellow flower with my phone, the image will look just about how I saw it with my own eyes. But what if we could see the flower from a different part of the electromagnetic spectrum? What if we could see less than 400 nm or greater than 700 nm? A bee, like many other insects, can see in the ultraviolet part of the spectrum which occupies the area below 400 nm. This “yellow” flower looks drastically different to us versus a bee.

In this article, we’re going to explore how images can be produced to show spectral information outside of our limited visual capacity, and take a look at the multi-spectral cameras used to make them. We’ll find that while it may be true that an image is worth a thousand words, it is also true that an image taken with a hyperspectral camera can be worth hundreds of thousands, if not millions, of useful data points. Continue reading “Hyperspectral Imaging – Seeing The Unseeable” →

Lithium Ion Versus LiPoly In An Aeronautical Context

October 23, 2017 by Brian Benchoff 32 Comments

When it comes to lithium batteries, you basically have two types. LiPoly batteries usually come in pouches wrapped in heat shrink, whereas lithium ion cells are best represented by the ubiquitous cylindrical 18650 cells. Are there exceptions? Yes. Is that nomenclature technically correct? No, LiPoly cells are technically, ‘lithium ion polymer cells’, but we’ll just ignore the ‘ion’ in that name for now.

Lithium ion cells are found in millions of ground-based modes of transportation, and LiPoly cells are the standard for drones and RC aircraft. [Tom Stanton] wondered why that was, so he decided to test the energy density per mass of these battery chemistries, and what he found was very interesting.

The goal of [Tom]’s experiment was to test LiPoly against lithium ion batteries in the context of a remote-controlled aircraft. Since weight is what determines flight time, cutting even a few grams from an airframe can vastly extend the capabilities of an aircraft. The test articles for this experiment come in the form of a standard 1800 mAh LiPoly battery and four 18650 cells wired together as a 3000 mAh battery. Here’s where things get interesting: the LiPoly battery weighs 216 grams for an energy density of 0.14 Watt-hours per gram. The lithium ion battery weighs 202 grams for an energy density of 0.25 Watt-hours per gram. If you just look at the math, all drones are doing it wrong. 18650 cells appear to have a much higher energy density per mass than the usual LiPoly cells. How does that hold up in a real-world test, though?

Using his neat plane with 3D printed wing ribs as the testbed, [Tom] plugged in the batteries and flew around a field for the better part of an afternoon. The LiPo flew for 41.5 minutes, whereas the much more energy dense lithium ion battery flew for 36.5 minutes. What’s going on here?

While the lithium ion battery has a much higher capacity, the problem here is the internal resistance of each battery chemistry. The end voltage for the LiPo was a bit lower than the lithium ion battery, suggesting the 18650 cells can be run down a bit further than [Tom]’s test protocol allowed. After recharging each of these batteries and doing a bit of math, [Tom] found the lithium ion batteries can fly for about twice as long as their LiPo counterparts. That means an incredibly long test of flying a plane in a circle over a field; not fun, but we are looking forward to other people replicating this experiment.

Continue reading “Lithium Ion Versus LiPoly In An Aeronautical Context” →

Dubai Police Test Quadcopter Motorcycle

October 16, 2017 by Al Williams 69 Comments

If you ever wish you could be on your quadcopter when you fly it, you will really want to see the video showing the Dubai police department testing the Hoverbike. The Russian company Hoversurf that markets the device doesn’t provide a lot of technical details, but it looks fairly simple. It is basically a motorcycle seat along with a big quadcopter. From the videos about the device, you can deduce that the pilot can control it or you can fly it remotely. You can see one of the videos, below.

There are a few things that worry us here. Of course, the huge spinning propellers as the pilot’s knee level should give you sweaty palms. In the demo, they even show the removal of the propeller guards before the test flight but let’s be honest, those don’t look like they would keep a falling pilot out of the rotors at all anyway. When looking beyond the hype we find it curious that the demo doesn’t show many (if any) shots of the pilot making a turn. The benefit of a vehicle like this to police should be maneuverability and from what we saw the Hoversurf is still limited.

So is it real? Hard to say. The short videos mostly show vertical or horizontal flight with no maneuvering. Is it hard to turn? Is the battery life really short? One other oddity: When we first saw a letter from the US Patent Office on their site, we thought they might have some new technology. However, that letter is simply showing they registered a trademark and doesn’t reference a patent. If there is a patent we want to know what is new and novel here.

Of course, we know it’s possible to build such a machine since we saw [Colin Furze] do it with two rotors instead of four. The US Department of Defense is working on something with a company called Malloy and there are other practical examples. There are also some less practical examples. What we’re really on the lookout for is a product that works so well it will actually be used. You know, like those Segways that airport police use, right?

We hope Hoversurf can bring this to market because we definitely want one. There’s no reason to think they can’t, but we do wish there were more details forthcoming.