Regular readers will have followed our series of posts looking at the issues surrounding reports of drones in proximity to aircraft, and will have noted that we recently asked our community how they would approach the detection and handling of marauding drones in controlled airspace. We are mere amateurs though by comparison to a team with its roots in Delft University of Technology’s Micro Air Vehicle Laboratory, because they have approached the problem through DroneClash, a spectacle best described as akin to a Robot Wars competition for drones. Their website states that “Anything goes, with one exception: nojamming“, and teams will do battle before an audience for a share in a considerable prize fund.
The fun is not however limited to team members. People in the audience will also be able to participate, by being invited to try their luck at bringing down a TinyWhoop that will periodically fly into the arena for a chance at their own prize. The ubiquitous cheap toy drone will be accessible through software, and would-be attackers are invited to register in advance to take a pop at it.
It looks as if DroneClash will be an unmissable event for anyone able to make it to the Netherlands on March 16th. We’ve mentioned it in past years, and we look forward to seeing what comes out of it this year too.
TinyWhoop header image: Dan Lundmark, (CC BY 2.0).
The wheels of government move slowly, far slower than the pace at which modern technology is evolving. So it’s not uncommon for laws and regulations to significantly lag behind the technology they’re aimed at reigning in. This can lead to something of a “Wild West” situation, which could either be seen as a good or bad thing depending on what side of the fence you’re on.
In the United States, it’s fair to say that we’ve officially moved past the “Wild West” stage when it comes to drone regulations. Which is not to say that remotely controlled (RC) aircraft were unregulated previously, but that the rules which governed them simply couldn’t keep up with the rapid evolution of the technology we’ve seen over the last few years. The previous FAA regulations for remotely operated aircraft were written in an era where RC flights were lower and slower, and long before remote video technology moved the operator out of the line of sight of their craft.
To address the spike in not only the capability of RC aircraft but their popularity, the Federal Aviation Administration was finally given the authority to oversee what are officially known as Unmanned Aerial Systems (UAS) with the repeal of Section 336 in the FAA Reauthorization Act of 2018. Section 336, known as the “Special Rule for Model Aircraft” was previously put in place to ensure the FAA’s authority was limited to “real” aircraft, and that small hobby RC aircraft would not be subject to the same scrutiny as their full-size counterparts. With Section 336 gone, one could interpret the new FAA directives as holding manned and unmanned aircraft and their operators to the same standards; an unreasonable position that many in the hobby strongly rejected.
At the time, the FAA argued that the repealing Section 336 would allow them to create new UAS regulations from a position of strength. In other words, start with harsh limits and regulations, and begin to whittle them down until a balance is found that everyone is happy with. U.S. Secretary of Transportation Elaine L. Chao has revealed the first of these refined rules are being worked on, and while they aren’t yet official, it seems like the FAA is keeping to their word of trying to find a reasonable middle ground for hobby fliers.
Catch up on your Hackaday with this week’s podcast. Mike and Elliot riff on the Bluepill (ST32F103 boards), blackest of black paints, hand-crafted sorting machines, a 3D printer bed leveling system that abuses some 2512 resistors, how cyborgs are going mainstream, and the need for more evidence around airport drone sightings.
Stream or download Episode 4 here, and subscribe to Hackaday on your favorite podcasting platform! You’ll find show notes after the break.
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Drone racing is nifty as heck, and a need all races share is a way to track lap times. One way to do it is to use transponders attached to each racer, and use a receiver unit of some kind to clock them as they pass by. People have rolled their own transponder designs with some success, but the next step is ditching add-on transponders entirely, and that’s exactly what the Delta 5 Race Timer project does.
A sample Delta 5 Race Timer build (Source: ET Heli)
The open-sourced design has a clever approach. In drone racing, each aircraft is remotely piloted over a wireless video link. Since every drone in a race already requires a video transmitter and its own channel on which to broadcast, the idea is to use the video signal as the transponder. As a result, no external hardware needs to be added to the aircraft. The tradeoff is that using the video signal in this way is trickier than a purpose-made transponder, but the hardware to do it is economical, accessible, and the design is well documented on GitHub.
The hardware consists of RX508 RX5808 video receiver PCBs modified slightly to enable them to communicate over SPI. Each RX508 RX5808 is attached to its own Arduino, which takes care of low-level communications. The Arduinos are themselves connected to a Raspberry Pi over I2C, allowing the Pi high-level control over the receivers while it serves up a web-enabled user interface. As a bonus, the Pi can do much more than simply act as a fancy stopwatch. The races themselves can be entirely organized and run through the web interface. The system is useful enough that other projects using its framework have popped up, such as the RotorHazard project by [PropWashed] which uses the same hardware design.
While rolling one’s own transponders is a good solution for getting your race on, using the video transmission signal to avoid transponders entirely is super clever. The fact that it can be done with inexpensive, off the shelf hardware is just icing on the cake.
There’s a new soap opera that I can’t stop watching. Actually, I wish I could change the channel but this is unfortunately happening in real life. It’s likely the ups and downs of drone sightings would be too far fetched for fiction anyway.
If you aren’t British, maybe you will know a little of our culture through the medium of television. We don’t all live in stately homes like Downton Abbey of course, instead we’re closer to the sometimes comedic sets, bad lighting, and ridiculously complicated lives of the residents of Coronation Street or of Albert Square in Eastenders that you may have flashed past late at night on a high-number channel.
Unfortunately it didn’t end there. We’re back once more to catch up with the latest events down on the tarmac, and come away with a fresh set of reasonable questions unanswered by the popular coverage of the matter.
When you think about all the forces that have to be balanced to keep a drone stable, it’s a wonder that the contraptions stay in the air at all. And when the only option for producing those forces is blowing around more or less air it’s natural to start looking for other, perhaps better ways to achieve flight control.
Taking a cue from the spacecraft industry, [Tom Stanton] decided to explore reaction wheels for controlling drones. The idea is simple – put a pair of relatively massive motorized wheels at right angles to each other on a drone, and use the forces they produce when they accelerate to control the drone’s pitch and roll. [Tom]’s video below gives a long and clear explanation of the physics involved before getting to the build, which results in an ungainly craft a little reminiscent of a lunar lander. The drone actually manages a few short, somewhat stable flights, but in general the reaction wheels don’t seem to be up to the task. [Tom] chalks this up to the fact that he’s using the current draw of each reaction wheel motor as a measure of its torque, which is not exactly correct for all situations. He suggests that motors with encoders might do a better job, but by the end of the video the little drone isn’t exactly in shape for continued experimentation.
The last few days have seen drone stories in the news, as London’s Gatwick airport remained closed for a couple of days amid a spate of drone reports. The police remained baffled, arrested a couple who turned out to be blameless, and finally admitted that there was a possibility the drone could not have existed at all. It emerged that a problem with the investigation lay in there being no means to detect a drone beyond the eyesight of people on the ground, and as we have explored in these pages already, eyewitness reports are not always trustworthy.
Not much use against a small and mostly plastic multirotor. Sixflashphoto [CC BY-SA 4.0]
Radar Can’t See Them
It seems odd at first sight, that a 21st century airport lacks the ability to spot a drone in the air above it, but a few calls to friends of Hackaday in the business made it clear that drones are extremely difficult to spot using the radar systems on a typical airport. A system designed to track huge metal airliners at significant altitude is not suitable for watching tiny mostly-plastic machines viewed side-on at the low altitudes. We’re told at best an intermittent trace appears, but for the majority of drones there is simply no trace on a radar screen.
We’re sure that some large players in the world of defence radar are queueing up to offer multi-million-dollar systems to airports worldwide, panicked into big spending by the Gatwick story, but idle hackerspace chat on the matter makes us ask the question: Just how difficult would it be to detect a drone in flight over an airport? A quick Google search reveals multiple products purporting to be drone detectors, but wouldn’t airports such as Gatwick already be using them if they were any good? The Hackaday readership never fail to impress us with their ingenuity, so how would you do it?
Can You Hear What You Can’t See?
It’s easy to pose that question as a Hackaday scribe, so to get the ball rolling here’s my first thought on how I’d do it. I always hear a multirotor and look up to see it, so I’d take the approach of listening for the distinctive sound of multirotor propellers. Could the auditory signature of high-RPM brushless motors be detected amidst the roar of sound near airports?
I’m imagining a network of Rasberry Pi boards each with a microphone attached, doing some real-time audio spectrum analysis to spot the likely frequency signature of the drone. Of course it’s easy to just say that as a hardware person with a background in the publishing business, so would a software specialist take that tack too? Or would you go for a radar approach, or perhaps even an infra-red one? Could you sense the heat signature of a multirotor, as their parts become quite hot in flight?
Whatever you think might work as a drone detection system, give it a spin in the comments. We’d suggest that people have the confidence to build something, and maybe even enter it in the Hackaday Prize when the time comes around. Come on, what have you got to lose!
![Not much use against a small and mostly plastic multirotor. Sixflashphoto [CC BY-SA 4.0]](https://hackaday.com/wp-content/uploads/2018/12/788px-KCMH_Radar.jpg)
