Easy UFO Lights On Your Drone For Halloween

Sometimes it’s not so much what you put together, it’s how you use it. The folks at Adafruit have put up a project on how to dress up your drone with ‘UFO lights’ just in time for Halloween. The project is a ring of RGB LEDs and a small microcontroller to give any quadcopter a spinning ‘tractor beam light’ effect. A 3D printed fixture handles attachment. If you’re using a DJI Phantom 4 like they are, you can power everything directly from the drone using a short USB cable, which means hardly any wiring work at all, and no permanent changes of any kind to the aircraft. Otherwise, you’re on your own for providing power but that’s probably well within the capabilities of anyone who messes with add-ons to hobby aircraft.

One thing this project demonstrates is how far things have come with regards to accessibility of parts and tools. A 3D printed fixture, an off-the-shelf RGB LED ring, and a drop-in software library for a small microcontroller makes this an afternoon project. The video (embedded below) also demonstrates how some unfamiliar lights and some darkness goes a long way toward turning the otherwise familiar Phantom quadcopter into a literal Unidentified Flying Object.

Continue reading “Easy UFO Lights On Your Drone For Halloween”

Improving Flying Drones By Mimicking Flying Squirrels

With the ability to independently adjust the thrust of each of their four motors, quadcopters are exceptionally agile compared to more traditional aircraft. But in an effort to create an even more maneuverable drone platform, a group of South Korean researchers have studied adding flying squirrel tech to quadcopters. Combined with machine learning, this is said to significantly increase the prototype’s agility in an obstacle course.

Flying squirrels (tribe Pteromyini)) have large skin flaps (patagium) between their wrists and ankles which they use to control their flight when they glide from tree to tree, along with their fluffy squirrel tail. With flights covering up to 90 meters, they also manage to use said tail and patagium to air brake, which prevents them from smacking with bone jarring velocities into a tree trunk.

By taking these principles and adding a similar mechanism to a quadcopter for extending a patagium-like membrane between its rotors, the researchers could develop a new controller (thrust-wing coordination control, TWCC), which manages the extending of the membranes in coordination with thrust from the brushless motors. Rather than relying on trial-and-error to develop the controller algorithms, the researchers trained a recurrent neural network (RNN) which was pre-trained prior to first flights using simulation data followed by supervised learning to refine the model.

During experiments with obstacle avoidance on a test-track, the RNN-based controller worked quite well compared to a regular quadcopter. A disadvantage is of course that the range of these flying squirrel drones is less due to the extra weight and drag, but if one were to make flying drones that will perch on surfaces between dizzying feats of agility in the air, this type of drone tech might just be the ticket.

Continue reading “Improving Flying Drones By Mimicking Flying Squirrels”

Flying Drones That Can Walk And Jump Into The Air: An Idea With Legs?

When we look at how everyone’s favorite flying dinosaurs get around, we can see that although they use their wings a lot too, their legs are at least as important. Even waddling or hopping about somewhat ungainly on legs is more energy efficient than short flights, and taking off from the ground is helped by jumping into the air with a powerful leap from one’s legs. Based on this reasoning, a team of researchers set out to give flying drones their own bird-inspired legs, with their findings published in Nature (preprint on ArXiv).

The prototype RAVEN (Robotic Avian-inspired Vehicle for multiple ENvironments) drone is capable of hopping, walking, jumping onto an obstacle and jumping for take-off. This allows the drone to get into the optimal position for take-off and store energy in its legs to give it a boost when it takes to the skies. As it turned out, having passive & flexible toes here was essential for stability when waddling around, while jumping tests showed that the RAVEN’s legs provided well over 90% of the required take-off speed.

During take-off experiments the drone was able to jump to an altitude of about 0.4 meters, which allows it to clear ground-based obstacles and makes any kind of ‘runway’ unnecessary. Much like with our avian dinosaur friends the laws of physics dictate that there are strong scaling limits, which is why a raven can use this technique, but a swan or similar still requires a bit of runway instead of jumping elegantly into the air for near-vertical take-off. For smaller flying drones this approach would however absolutely seem to have legs.

Continue reading “Flying Drones That Can Walk And Jump Into The Air: An Idea With Legs?”

Automated Weed Spraying Drone Needs No Human Intervention

Battling weeds can be expensive, labor intensive and use large amounts of chemicals. To help make this easier [NathanBuilds] has developed  V2 of his open-source drone weed spraying system, complete with automated battery swaps, herbicide refills, and an AI vision system for weed identification.

The drone has a 3D printed frame, doubling as a chemical reservoir. V1 used a off-the-shelf frame, with separate tank. Surprisingly, it doesn’t look like [Nathan] had issues with leaks between the layer lines. For autonomous missions, it uses ArduPilot running on a PixHawk, coupled with RTK GPS for cm-level accuracy and a LiDAR altimeter. [Nathan] demonstrated the system in a field where he is trying to eradicate invasive blackberry bushes while minimizing the effect on the native prairie grass. He uses a custom image classification model running on a Raspberry Pi Zero, which only switches on the sprayers when it sees blackberry bushes in the frame. The Raspberry Pi Global Shutter camera is used to get blur-free images.

At just 305×305 mm (1×1 ft), the drone has limited herbicide capacity, and we expect the flights to be fairly short. For the automated pit stops, the drone lands on a 6×8 ft pad, where a motorized capture system pulls the drone into the reload bay. Here a linear actuator pushes a new battery into the side of the drone while pushing the spend battery one out the other side. The battery unit is a normal LiPo battery in 3D-printed frame. The terminal are connected to copper wire and tape contacts on the outside the battery unit, which connect to matching contacts in the drone and charging receptacles. This means the battery can easily short if it touches a metal surface, but a minor redesign could solve this quickly. There are revolving receptacles on either side of the reload bay, which immediately start charging the battery when ejected from the drone.

Developing a fully integrated system like this is no small task, and it shows a lot of potential. It might look a little rough around the edges, but [Nathan] has released all the design files and detailed video tutorials for all the subsystems, so it’s ready for refinement.

Continue reading “Automated Weed Spraying Drone Needs No Human Intervention”

THOR Microwaves Drone Swarms

In recent years small drones have gone from being toys and photography tools to a deadly threat on the battlefield. Kamikaze drones have become especially prominent in the news due to their use in the war in Ukraine by both sides. While we haven’t seen coordinated swarms being actively employed on the modern battlefield, it’s likely only a matter of time, making drone swarm defense an active field of development in the industry.

The US Air Force Research Laboratory recently conducted tests and a demonstration of an anti-drone weapon that uses pulses of high-power microwave energy to fry the electronics of a swarm of drones. Named the Tactical High-power Operational Responder, or THOR  (presumably they picked the acronym first), it’s housed in a 20ft shipping container with large microwave antenna on top. The form factor is important because a weapon is only useful if it can reach the battlefield, and this can fit in the back of a C130.

THOR likely functions similarly to a shotgun, with a relatively large effective “beam.” This would have added advantages like frying multiple drones with one pulse and not needing pinpoint tracking and aiming tech required for projectile and laser-based weapons. Depending on its range and directivity, THOR might come with the downside of collateral damage to electronics close to its line of fire.

Drone swarms are of course the other side of this arms race, but fortunately they also have non-destructive uses like lights shows and perhaps even 3D printing.

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?”

Ground Effect Drone Flies Autonomously

There are a number of famous (yet fictional) sea monsters in the lakes and oceans around the world, but in the Caspian Sea one turned out to be real. This is where the first vehicles specifically built to take advantage of the ground effect were built by the Soviet Union, and one of the first was known as the Caspian Sea Monster due to the mystery surrounding its discovery. While these unique airplane/boat hybrids were eventually abandoned after several were built for military use, the style of aircraft still has some niche uses and can even be used as a platform for autonomous drones.

This build from [Think Flight] started off as a simple foam model of just such a ground effect vehicle (or “ekranoplan”) in his driveway. With a few test flights the model was refined enough to attach a small propeller and battery. The location of the propeller changed from rear-mounted to front-mounted and then back to rear-mounted for the final version, with each configuration having different advantages and disadvantages. The final model includes an Arudino running an autopilot program called Ardupilot, and with an air speed sensor installed the drone is able to maintain flight in the ground effect and autonomously navigate pre-programmed waypoints around a lake at high speed.

For a Cold War technology that’s been largely abandoned by militaries in favor of other modes of transportation due to its limited use case and extremely narrow flight tolerances, ground effect vehicles are relatively popular as remote controlled vehicles. This RC ekranoplan used the same Ardupilot software but paired with a LIDAR system instead of GPS to navigate its way around its environment.

Thanks to [TTN] for the tip!

Continue reading “Ground Effect Drone Flies Autonomously”