Quadcopters are fantastical things, and now come in a huge variety of flavours, from lithe featherweight racers to industrial-grade filming rigs worth tens of thousands of dollars. The Beatle-1 from [masterdezign] comes in at the smaller scale, and its body was created entirely in code.
To create the Beatle-1, [masterdezign] used OpenSCAD, a 3D modelling program that uses code rather than visual tools for producing geometry. Thus, with a series of Boolean operations, extrusions and rotations, a basic lightweight quadcopter frame is created in a handful of lines of text. Then, it’s just a simple job of 3D printing the parts, wiring up four Olimex F1607 motors and hooking up a flight controller and the little drone is ready for takeoff.
Apparently, if the GPS on your shiny new DJI FPV Drone detects that it’s not in the United States, it will turn down its transmitter power so as not to run afoul of the more restrictive radio limits elsewhere around the globe. So while all the countries that have put boots on the Moon get to enjoy the full 1,412 mW of power the hardware is capable of, the drone’s software limits everyone else to a paltry 25 mW. As you can imagine, that leads to a considerable performance penalty in terms of range.
But not anymore. A web-based tool called B3YOND promises to reinstate the full power of your DJI FPV Drone no matter where you live by tricking it into believing it’s in the USA. Developed by the team at [D3VL], the unlocking tool uses the new Web Serial API to send the appropriate “FCC Mode” command to the drone’s FPV goggles over USB. Everything is automated, so this hack is available to anyone who’s running a recent version of Chrome or Edge and can click a button a few times.
There’s no source code available yet, though the page does mention they will be putting up a GitHub repository soon. In the meantime, [D3VL] have documented the command packet that needs to be sent to the drone over its MODBUS-like serial protocol for others who might want to roll their own solution. There’s currently an offline Windows-only tool up for download as well, and it sounds like stand-alone versions for Mac and Android are also in the works.
It should probably go without saying that if you need to use this tool, you’ll potentially be violating some laws. In many European countries, 25 mW is the maximum unlicensed transmitter power allowed for UAVs, so that’s certainly something to keep in mind before you flip the switch. Hackaday isn’t in the business of dispensing legal advice, but that said, we wouldn’t want to be caught transmitting at nearly 60 times the legal limit.
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.
The sky crane system used on the Perseverance and Curiosity Mars rovers is a challenging control system problem that piqued [Nicholas Rehm]’s curiosity. Constrained to Earth, he decided to investigate the problem using a drone and a rock.
The setup and the tests are simple, but clearly illustrate the problem faced by NASA engineers. [Nicholas] attached a winch mechanism to the bottom of a racing-type quadcopter, and tied a mass to the end of the winch line. At first, he built a foam model of the rover, but it proved to be unstable in the wake of the quadcopter’s propellers, so he used a rock instead. The tests start with the quadcopter taking off with the rock completely retracted, which is then slowly lowered in flight until it reaches the end of the line and drops free. As soon as the rock was lowered, it started swinging like a pendulum, which only got worse as the line got longer. [Nicholas] attempted to reduce the oscillations with manual control inputs, but this only made it worse. The quadcopter is also running [Nicholas]’s own dRehmFlight flight controller that handles stabilization, but it does not account for the swinging mass.
[Nicholas] goes into detail on the dynamics of this system, which is basically a two-body pendulum. The challenges of accurately controlling a two-body pendulum are one of the main reasons the sky crane concept was shelved when first proposed in 1999. Any horizontal movement of either the drone or the rock exerts a force on the other body and will cause a pendulum motion to start, which the control system will not be able to recover from if it does not account for it. The real sky crane probably has some sort of angle sensing on the tether which can be used to compensate for any motion of the suspended rover. Continue reading “Demonstrating The Mars Rover Pendulum Problem With A Drone On Earth”→
A reality of flying RC aircraft is that at some point, one of your birds is going to fall in the line of duty. It could get lost in the clouds never to be seen again, or perhaps it will become suddenly reacquainted with terra firma. Whatever the reason, your overall enjoyment of the hobby depends greatly on how well you can adapt to the occasional loss.
Based on what we’ve seen so far, we’d say [Rural Flyer] has the right temperament for the job. After losing one of his quadcopters in an unfortunate FPV incident, he decided to repurpose the proprietary gimbal it left behind. If he still had the drone he could have slipped a logic analyzer in between its connection with the motorized camera to sniff out the communication protocol, but since that was no longer an option, he had to get a little creative.
Figuring out the power side of things was easy enough thanks to the silkscreen on the camera’s board, and a common 5 V battery eliminator circuit (BEC) connected to the drone’s 7.4 V battery pack got it online. A cobbled together adapter allowed him to mount it to one of his other quads, but unfortunately the angle wasn’t quite right.
[Rural Flyer] wanted the camera tilted down about 15 degrees, but since he didn’t know how to talk to it, he employed a clever brute force solution. After identifying the accelerometer board responsible for determining the camera’s position, he use a glob of hot glue to push the sensor off of the horizontal. Providing this physical offset to the sensor data caused the camera to automatically move itself to exactly where he wanted it.
Apparently, in the drone scene, sticker wraps are popular for a custom aesthetic. [Useless Mod] wanted to go a little further, however, and decided to build a full crystal enclosure for his Mavic Mini, facing some hurdles along the way. (Video, embedded below.)
The first stage of the build was disassembly, with the compact 249 gram drone requiring a deft touch to avoid damaging the delicate ribbon cables and mechanisms inside. With the drone stripped down to its bare components, a silicone mould was made of each individual piece of the case, with new parts being cast in clear epoxy. It’s not a job for the faint of heart, with many undercuts and complex features to contend with. However, [Useless Mod] managed to produce the parts and get it all back together.
An initial test flight ended poorly, when the drone entered an uncontrollable wobble due to the case not being fully assembled. However, with fresh internals and with everything properly put together, everything worked! It’s not a build we’d suggest for the inexperienced, as the moulds required are complex and the electronics quite fragile. The final result is a good one though, and it even weighs 10 grams less than the original casing!
Last week we featured a story on the new rules regarding drone identification going into effect in the US. If you missed the article, the short story is that almost all unmanned aircraft will soon need to transmit their position, altitude, speed, and serial number, as well as the position of its operator, likely via WiFi or Bluetooth. The FAA’s rule change isn’t sitting well with Wing, the drone-based delivery subsidiary of megacorporation Alphabet. In their view, local broadcast of flight particulars would be an invasion of privacy, since observers snooping in on Remote ID traffic could, say, infer that a drone going between a pharmacy and a neighbor’s home might mean that someone is sick. They have a point, but how a Google company managed to cut through the thick clouds of irony to complain about privacy concerns and the rise of the surveillance state is mind boggling.
Speaking of regulatory burdens, it appears that getting an amateur radio license is no longer quite the deal that it once was. The Federal Communications Commission has adopted a $35 fee for new amateur radio licenses, license renewals, and changes to existing licenses, like vanity call signs. While $35 isn’t cheap, it’s not the end of the world, and it’s better than the $50 fee that the FCC was originally proposing. Still, it seems a bit steep for something that’s largely automated. In any case, it looks like we’re still good to go with our “$50 Ham” series.
Staying on the topic of amateur radio for a minute, it looks like there will be a new digital mode to explore soon. The change will come when version 2.4.0 of WSJT-X, the program that forms the heart of digital modes like WSPR and FT8, is released. The newcomer is called Q65, and it’s basically a follow-on to the current QRA64 weak-signal mode. Q65 is optimized for weak, rapidly fading signals in the VHF bands and higher, so it’s likely to prove popular with Earth-Moon-Earth fans and those who like to do things like bounce their signals off of meteor trails. We’d think Q65 should enable airliner-bounce too. We’ll be keen to give it a try whenever it comes out.
Look, we know it’s hard to get used to writing the correct year once a new one rolls around, and that time has taken on a relative feeling in these pandemic times. But we’re pretty sure it isn’t April yet, which is the most reasonable explanation for an ad purporting the unholy coupling of a gaming PC and mass-market fried foods. We strongly suspect this is just a marketing stunt between Cooler Master and Yum! Brands, but taken at face value, the KFConsole — it’s not a gaming console, it’s at best a pre-built gaming PC — is supposed to use excess heat to keep your DoorDashed order of KFC warm while you play. In a year full of incredibly stupid things, this one is clearly in the top five.
And finally, it looks like we can all breathe a sigh of relief that our airline pilots, or at least a subset of them, aren’t seeing things. There has been a steady stream of reports from pilots flying in and out of Los Angeles lately of a person in a jetpack buzzing around. Well, someone finally captured video of the daredevil, and even though it’s shaky and unclear — as are seemingly all videos of cryptids — it sure seems to be a human-sized biped flying around in a standing position. The video description says this was shot by a flight instructor at 3,000 feet (914 meters) near Palos Verdes with Catalina Island in the background. That’s about 20 miles (32 km) from the mainland, so whatever this person is flying has amazing range. And, the pilot has incredible faith in the equipment — that’s a long way to fall in something with the same glide ratio as a brick.