3D Printed Mini Drone Test Gimbal

Drones are a pain, especially mini ones. When you are designing, building (or even reviewing) them, they inevitably fly off in some random direction, inevitably towards your long-suffering dog, hit him in the butt and send him scuttling off in search of a quieter spot for a nap.

[Tristan Dijkstra] and [Suryansh Sharma] have a solution: a mini-drone test gimbal. The two are in the the Networked Systems group and the Biomorphic Intelligence Lab who use CrazyFlie drones in their work, which require regular calibration and testing. This excellent design allows the drone to rotate in three dimensions, while still remaining safely contained. That means I could test the flight characteristics of a drone without endangering my dogs important napping schedule.

Efforts involved attaching a light tether that restricts the drone until we know how the it flies, but what usually happens is that the tether gets trapped in a rotor, or the tether gets tight and the drone freaks out and crashes into the ground.

Using a gimbal is far more elegant, because it allows the drone to rotate freely in three dimensions, so the basic features of the drone can be established before you let it loose in the skies.

The gimbal was designed with the CrazyFlie in mind, but as there’s nothing more exotic holding the craft down than a zip tie, it should work with similarly sized quadcopters.

Continue reading “3D Printed Mini Drone Test Gimbal”

Is An ADS-B Receiver The Solution For Drone Pilots?

Over the years here at Hackaday, we’ve covered a range of stories about the ongoing panic surrounding drone flights. From plastic bags reported as drone incidents through to airports closed with no evidence of drones being involved, it’s clear that drone fliers are an embattled group facing a legal and aeronautical establishment that seems to understand little about them or their craft.

It sometimes seems to be a no-win situation for fliers, but perhaps [XJet] has something which might improve matters. He’s published a video showing off a portable ADS-B receiver which could be used by drone pilots to check for any aircraft in the vicinity and perhaps more importantly allow the drone community to take the moral high ground when problems occur.

The receiver isn’t particularly special, being a Raspberry Pi with LCD screen and an RTL-SDR receiver in a nice 3D printed enclosure. He says he’ll be publishing all software and build details in due course. But it’s the accessibility which makes it such a good idea, instead of being a very expensive safety device it’s a receiver that could probably be made with a less powerful Pi for under $100.

There is of course a flaw in the plan, that not all pilots are concerned enough for their safety to fit an ADS-B transponder to their aircraft, and so are invisible to both the thus-equipped drone pilot and air traffic control alike. This puts the onus on pilots to consider ADS-B an essential, but from the drone flier’s point of view we’d consider that a spotter should be part of their group anyway.

Curious what the fuss is about? Let us take you on a journey.

Continue reading “Is An ADS-B Receiver The Solution For Drone Pilots?”

Drone Hits Plane — And This Time It’s A Real (Police) One!

Over the years we’ve brought you many stories that follow the world of aviation as it struggles with the arrival of multirotors. We’ve seen phantom drone encounters cause panics and even shut airports, but it’s been vanishingly rare for such a story to have a basis in evidence. But here we are at last with a drone-aircraft collision story that involves a real drone. This time there’s a twist though, instead of one piloted by a multirotor enthusiast that would prompt a full-on media panic, it’s a police drone that collided with a Cesna landing at Toronto’s Buttonville airport. The York Regional Police craft was part of an operation unrelated to the airport, and its collision with the aircraft on August 10th was enough to make a significant dent in its engine cowling. The police are reported to be awaiting the result of an official investigation in the incident.

This is newsworthy in itself because despite several years and significant resources being devoted to the problem of drones hitting planes, demonstrable cases remain vanishingly rare. The machine in this case being a police one will we expect result in many fewer column inches for the event than had it been flown at the hands of a private multirotor pilot, serving only to heighten the contrast with coverage of previous events such as the Gatwick closure lacking any drone evidence.

It’s picking an easy target to lay into the Your Regional Police over this incident, but it is worth making the point that their reaction would have been disproportionately larger had the drone not been theirs. The CTV news report mentions that air traffic regulators were unaware of the drone’s presence:

NAV Canada, the country’s air navigation service provider, had not been notified about the YRP drone, Transport Canada said.

Given the evident danger to aviation caused by their actions it’s not unreasonable to demand that the officers concerned face the same penalties as would any other multirotor pilot who caused such an incident. We aren’t holding our breath though.

Header image: Raysonho @ Open Grid Scheduler / Grid Engine, CC0.

The Gatwick Drone: Little By Little, The Story Continues To Unravel

If you remember the crazy events in the winter of 2018 as two airports were closed over reports of drone sightings, you might be interested to hear that there’s still a trickle of information about those happenings making it into the public domain as Freedom of Information responses.

Three Christmases ago the news media was gripped by a new menace, that of rogue drones terrorising aircraft. The UK’s Gatwick airport had been closed for several days following a spate of drone sightings, and authorities thundered about he dire punishments which would be visited upon the perpetrators when they were caught. A couple were arrested and later quietly released, and after a lot of fuss the story quietly disappeared.

Received Opinion had it that a drone had closed an airport, but drone enthusiasts, and Hackaday as a publication in their sphere, were asking awkward questions about why no tangible evidence of a drone ever having been present had appeared. Gradually the story unravelled with the police and aviation authorities quietly admitting that they had no evidence of a drone, and a dedicated band of drone enthusiasts has continues to pursue the truth about those few winter nights in 2018. The latest results chase up the possibility that the CAA might have received a description of the drone, and why when a fully functional drone detection system had been deployed and detected nothing they continued with the farce of closing the airport.

Perhaps the saddest thing about these and other revelations about the incident which have been teased from the authorities is that while they should fire up a scandal, it seems inevitable that they won’t. The police, the government, and the CAA have no desire to be reminded of their mishandling of the event, neither except for a rare bit of mild questioning do the media wish to be held to account for the execrable quality of their reporting. The couple who were wrongly arrested have not held back in their condemnation, but without the attention of any powerful vested interests it seems that some of the measures brought in as a response will never be questioned. All we can do is report any new developments in our little corner of the Internet, and of course keep you up to date with any fresh UK police drone paranoia.

Learn Multirotors From First Principles

Multirotors, or drones as they’re popularly called, are so ubiquitous as to have become a $10 toy. They’re no less fun to fly for it though, and learning how they work is no less fascinating. It’s something [Science Buddies] has addressed in a series of videos examining them from first principles. They may be aimed at youngsters, but they’re still an entertaining enough watch for those of advancing years.

Instead of starting with a multirotor control board, the video takes four little DC motors and two popsicle sticks to make a rudimentary drone frame. Then with the help of dowels and springs it tethers the craft as the control mechanisms are explained bit by bit, from simple on-off motor control through proportional control to adding an Arduino and following through to how a multirotor stays in flight. It’s instructional and fun to watch, and maybe even for some of us, a chance to learn something.

We’ve had multirotor projects aplenty here over the years, but how about something completely different made from popsicle sticks?

Continue reading “Learn Multirotors From First Principles”

Lost A Lightweight Quadcopter? Here Are The Best Ways To Find It

Lost aircraft are harder to find when they are physically small to begin with. Not only are they harder to see, but the smaller units lack features like GPS tracking; it’s not normally possible to add it to a tiny aircraft that can’t handle much more than its own weight in the first place. As a result, little lost quads tend to be trickier to recover in general.

Fluorescent tape adds negligible weight, and will glow brightly at night under a UV light.

The good news is that [Eric Brasseur] has shared some concise tips on how to more easily locate and recover lost aircraft, especially lightweight ones. Recovering aircraft is something every aircraft hobbyist has had to deal with in one way or another, but [Eric] really has gathered an impressive list of tricks and techniques, and some of them go into some really useful additional detail. It occurs to us that a lot of these tips could apply equally well to outdoor robots, or rovers.

Even simple techniques can be refined. For example, using bright colors on an aircraft is an obvious way to increase visibility, but some colors are better choices than others. Bright orange, white, and red are good choices because they are easily detected by the human eye while still being uncommon in nature. Violet, blue, and even cyan on the other hand may seem to be good choices when viewed indoors on a workbench, but if the quad is stuck in dark bushes, those colors will no longer stand out. Another good tip is to consider also adding a few patches of fluorescent tape to the aircraft. If all else fails, return at night with a UV lamp; those patches will glow brightly, and be easily seen from tens of meters.

Some of the tips are used while the device still has power, while others don’t depend on batteries holding out. [Eric] does a great job of summing up those and many more, so take a look. They might come in handy when test flying quadcopters that are little more than an 18650 cell, motors, and a 3D-printable frame.

One Wheel Is All We Need To Roll Into Better Multirotor Efficiency

Multirotor aircraft enjoy many intrinsic advantages, but as machines that fight gravity with brute force, energy efficiency is not considered among them. In the interest of stretching range, several air-ground hybrid designs have been explored. Flying cars, basically, to run on the ground when it isn’t strictly necessary to be airborne. But they all share the same challenge: components that make a car work well on the ground are range-sapping dead weight while in the air. [Youming Qin et al.] explored cutting that dead weight as much as possible and came up with Hybrid Aerial-Ground Locomotion with a Single Passive Wheel.

As the paper’s title made clear, they went full minimalist with this design. Gone are the driveshaft, brakes, steering, even other wheels. All that remained is a single unpowered wheel bolted to the bottom of their dual-rotor flying machine. Minimizing the impact on flight characteristics is great, but how would that work on the ground? As a tradeoff, these rotors have to keep spinning even while in “ground mode”. They are responsible for keeping the machine upright, and they also have to handle tasks like steering. These and other control algorithm problems had to be sorted out before evaluating whether such a compromised ground vehicle is worth the trouble.

Happily, the result is a resounding “yes”. Even though the rotors have to continue running to do different jobs while on the ground, that was still far less effort than hovering in the air. Power consumption measurements indicate savings of up to 77%, and there are a lot of potential venues for tuning still awaiting future exploration. Among them is to better understand interaction with ground effect, which is something we’ve seen enable novel designs. This isn’t exactly the flying car we were promised, but its development will still be interesting to watch among all the other neat ideas under development to keep multirotors in the air longer.

[IROS 2020 Presentation video (duration 10:49) requires no-cost registration, available until at least Nov. 25th 2020. Forty-two second summary embedded below]

Continue reading “One Wheel Is All We Need To Roll Into Better Multirotor Efficiency”