Tilt-Rotor Plane Needs Flight Controller Hack to Get Airborne

Part of the charm of quadcopters is the challenge that building and flying them presents. In need of complex sensors and computational power to just get off the ground and under tremendous stresses thanks to their massively powerful motors, they often seem only barely controlled in flight. Despite these challenges, quadcopter flight has been reduced to practice in many ways, leaving hobbyists in search of another challenge.

[Tom Stanton] is scratching his creative itch with this radio-controlled tilt-rotor airplane that presents some unique problems and opportunities. Tilt-rotor planes are, as the name implies, able to swivel their propellors and transition them from providing forward thrust to providing verticle lift. With the rotors providing lift, the aircraft is able to hover and perform vertical take-off and landing (VTOL); switched to thrust mode, wings provide the lift for horizontal flight.

[Tom]’s realization of this design seems simple – a spar running through the wing holding BLDC motors and props is swiveled through 90° by a servo to transition the aircraft. Standard control surfaces on the wings and tail take care of horizontal flight. Actually getting an off-the-shelf flight controller to deal with the transitions was tricky. [Tom] ended up adding an Arduino to intercept the PWM signals the flight controller normally sends directly to the servos and speed controls to provide the coordination needed for a smooth transition. Full details in the video below, and some test flights which show that an RC VTOL is anything but a beginner’s plane.

[Tom] is proving himself to be quite the Renaissance man these days. Between air-powered piston engines, over-balance trebuchets, and popping the perfect wheelie, he seems to have covered all the bases and done his best to keep our tip line stocked.

Continue reading “Tilt-Rotor Plane Needs Flight Controller Hack to Get Airborne”

Flying Human Head Lands Just in Time for Halloween

We love the fall here at Hackaday. The nights are cooler, the leaves are changing, and our tip line starts lighting up with some of the craziest things we’ve ever seen. Something about terrifying children of all ages just really speaks to the hacker mindset. That sounds bad, but we’re sure there’s a positive message in there someplace if you care to look hard enough.

Today’s abomination is a truly horrifying human head quadcopter, which exists for literally no other reason than to freak people out. We love it. Created by [Josh] and a few friends, the “HeadOCopter” is built around a meticulously detailed 3D print of his own head. This thing is so purpose-built that they didn’t even put landing gear on it: there’s no point sitting on the ground when you’re in the business of terrorizing people from above.

Sure, you could do this project with a cheap plastic skull. But there’s no way it would have the same effect. [Josh] created this monstrosity by scanning his own head with the Microsoft Kinect, cleaning the model up in ZBrush, adding in mounts for hardware, and 3D printing the result. After doing some smoothing and filling, the head got passed off to artist [Lisa Svingos] for the final painting. He even thought to include an FPV camera where one of his eyes should be, giving a whole new meaning to the term.

As for the quadcopter hardware itself, it uses a BrainFPV RADIX flight controller (get it?) and 12×5 props on Sunnysky V3508 motors with 30A BLHELI ESCs. Measuring 1 meter (3.2 feet) from motor to motor, it’s an impressive piece of hardware itself; head or no head.

This project reminds us of the flying ghost we saw years back, but we have to admit, this raises the bar pretty high. We’re almost afraid to see what comes next.

Continue reading “Flying Human Head Lands Just in Time for Halloween”

Keep ‘Em Flying with this Monster DIY Battery

If you’ve spent an afternoon at the sticks of a remote-controlled aircraft, you’re probably well aware of the great limiter for such exploits: battery life. In the days when most RC aircraft were gas powered it was easy to cart along some extra fuel to keep the good times rolling, but now that everything except big scale models are using electric motors, RC pilots are looking for better ways to charge their batteries in the field.

Though it might seem counter-intuitive, [Adam Pyschny] is of the opinion that the best way to keep his quadcopter batteries charged is to simply use another, much bigger, battery. Rather than mess around with inverters or generators, he can simply use a DC-to-DC battery charger and his huge custom-built battery pack to keep flying.

The pack contains 36 Samsung INR18650-35E 3500mAh cells, which gives it a total capacity of 454Wh. At 1965 grams (4.3 lbs) the pack isn’t exactly a featherweight, but it’s significantly lighter than carting a small generator or even a lead-acid battery to the field.

[Adam] designed a slick case in FreeCAD and printed it in Minadax ASA-X filament, which is specifically designed for outdoor use. A particularly nice detail in the case is that the balance connector (used to charge the cells) is cleanly integrated into the side of the pack, rather than just flapping around in the breeze; which annoyingly seems the norm even on commercially produced batteries.

An interesting next step for this project would be the addition of a solar panel and charge controller to help recover in-between charges. Beyond an automated platform to swap the batteries for you, a DIY pack like this might be the easiest way to maximize the amount of time your RC aircraft are in the air where they belong.

Open Source Paramotor Using Quadcopter Tech

Have you ever dreamed of flying, but lack the funds to buy your own airplane, the time to learn, or the whole hangar and airstrip thing? The answer might be in a class of ultralight aircraft called powered paragliders, which consist of a soft inflatable wing and a motor on your back. As you may have guessed, the motor is known as a paramotor, and it’s probably one of the simplest powered aircraft in existence. Usually little more than big propeller, a handheld throttle, and a gas engine.

But not always. The OpenPPG project aims to create a low-cost paramotor with electronics and motors intended for heavyweight multicopters. It provides thrust comparable to gas paramotors for 20 to 40 minutes of flight time, all while being cheaper and easier to maintain. The whole project is open source, so if you don’t want to buy one of their kits or assembled versions, you’re free to use and remix the design into a personal aircraft of your own creation.

It’s still going to cost for a few thousand USD to get a complete paraglider going, but at least you won’t need to pay hangar fees. Thanks to the design which utilizes carbon fiber plates and some clever hinges, the whole thing folds up into a easier to transport and store shape than traditional paramotors with one large propeller. Plus it doesn’t hurt that it looks a lot cooler.

Not only are the motors and speed controls borrowed from the world of quadcopters, but so is the physical layout. A traditional paramotor suffers from a torque issue, as the big propeller wants to twist the motor (and the human daring enough to strap it to his or her back) in the opposite direction. This effect is compensated for in traditional gas-powered paramotor by doing things like mounting the motor at an angle to produce an offset thrust. But like a quadcopter the OpenPPG uses counter-rotating propellers which counteract each others thrust, removing the torque placed on the pilot and simplifying design of the paraglider as a whole.

If you still insist on the fixed-wing experience, you could always get some foam board and hope for the best.

[Thanks to Luke for the tip.]

Continue reading “Open Source Paramotor Using Quadcopter Tech”

Quadcopter Hardware Gets Classic Lake Bed Test

You’d be hard pressed to find an aircraft that wasn’t designed and tested without extensive use of simulation. Whether it’s the classic approach of using a scale model in a wind tunnel or more modern techniques such as computational fluid dynamics, a lot of testing happens before any actual hardware gets bolted together. But at some point the real deal needs to get a shakedown flight, and historically a favorite testing ground has been the massive dry lake beds in the Western United States. The weather is always clear, the ground is smooth, and there’s nobody for miles around.

Thanks to [James] and [Tyler] at Propwashed, that same classic lake bed approach to real-world testing has now been brought to the world of high performance quadcopter gear. By mounting a computer controlled thrust stand to the back of their pickup truck and driving through the El Mirage dry lake bed in the Mojave Desert, they were able to conduct realistic tests on how different propellers operate during flight. The data collected provides an interesting illustration of the inverse relationship airspeed has with generated thrust, but also shows that not all props are created equal.

The first post in the series goes over their testing set-up and overall procedure. On a tower in the truck’s bed a EFAW 2407 2500kV motor was mounted on a Series 1520 thrust stand by RCBenchmark. This stand connects to the computer and offers a scripted environment which can be used to not only control the motor but monitor variables like power consumption, RPM, and of course thrust. While there was some thought given to powering the rig from the truck’s electrical system, in the end they used Turnigy 6000mAh 4S battery packs to keep things simple.

A script was written for the thrust stand which would ramp the throttle from 0% up to 70% over 30 seconds, and then hold it at that level for 5 seconds. This script was run when the truck was at a standstill, and then repeated with the truck travelling at increasingly faster speeds up to 90 MPH. This procedure was repeated for each of the 15 props tested, and the resulting data graphed to compare how they performed.

The end result was that lower pitch props with fewer blades seemed to be the best overall performers. This isn’t a huge surprise given what the community has found through trial and error, but it’s always good to have hard data to back up anecdotal findings. There were however a few standout props which performed better at high speeds than others, which might be worth looking into if you’re really trying to push the envelope in terms of airspeed.

As quadcopters (or “drones”, if you must) have exploded in popularity, we’re starting to see more and more research and experimentation done with RC hardware. From a detailed electrical analysis of hobby motors to quantifying the latency of different transmitters.

Simple Quadcopter Testbed Clears The Air For Easy Algorithm Development

We don’t have to tell you that drones are all the rage. But while new commercial models are being released all the time, and new parts get released for the makers, the basic technology used in the hardware hasn’t changed in the last few years. Sure, we’ve added more sensors, increased computing power, and improved the efficiency, but the key developments come in the software: you only have to look at the latest models on the market, or the frequency of Git commits to Betaflight, Butterflight, Cleanflight, etc.

With this in mind, for a Hackaday prize entry [int-smart] is working on a quadcopter testbed for developing algorithms, specifically localization and mapping. The aim of the project is to eventually make it as easy as possible to get off the ground and start writing code, as well as to integrate mapping algorithms with Ardupilot through ROS.

The initial idea was to use a Beaglebone Blue and some cheap hobby hardware which is fairly standard for a drone of this size: 1250 kv motors and SimonK ESCs, mounted on an f450 flame wheel style frame. However, it looks like an off-the-shelf solution might be even simpler if it can be made to work with ROS. A Scanse Sweep LIDAR sensor provides point cloud data, which is then munched with some Iterative Closest Point (ICP) processing. If you like math then it’s definitely worth reading the project logs, as some of the algorithms are explained there.

It might be fun to add FPV to this system to see how the mapping algorithms are performing from the perspective of the drone. And just because it’s awesome. FPV is also a fertile area for hacking: we particularly love this FPV tracker which rotates itself to get the best signal, and this 3D FPV setup using two cameras.

“Watch Dogs” Inspired Hacking Drone Takes Flight

They say that life imitates art, which in modern parlance basically means if you see something cool in a video game, movie or TV show, you might be inclined to try and build your own version. Naturally, such things generally come in the form of simple props, perhaps with the occasional embedded LED or noise making circuit. It’s not as if you can really build a phaser from Star Trek or a phone booth that’s bigger on the inside.

But after seeing the hacking quadcopter featured in the video game Watch Dogs 2, [Glytch] was inspired to start work on a real-world version. It doesn’t look much like the drone from the game, but that was never the point. The idea was to see how practical a small flying penetration testing platform is with current technology, and judging by the final build, we’d say he got his answer.

All the flight electronics are off the shelf quadcopter gear. It’s running on a Betaflight OMNIBUS F4 Pro V2 Flight controller with an M8N GPS mounted in the front and controlling the 2006 2400KV motors with a DYS F20A ESC. Interestingly [Glytch] is experimenting with using LG HG2 lithium-ion cells to power the quad rather than the more traditional lithium-polymer pack, though he does mention there are some issues with the voltage curve between the two battery technologies.

But the real star of the show is the payload: a Hak5 Pineapple Nano. As the Pineapple provides a turn-key penetration testing platform on its own, [Glytch] just needed a way to safely carry it and keep it powered. The custom frame keeps it snug, and the 5 Volt Battery Eliminator Circuit (BEC) on the DYS F20A ESC combined with a female USB port allows powering the Pineapple without having to make any hardware modifications.

We’ve seen quadcopters with digital weaponry before, though not nearly as many as you might think. But as even the toy grade quadcopters become increasingly capable, we imagine the airborne hacking revolution isn’t far away.

Continue reading ““Watch Dogs” Inspired Hacking Drone Takes Flight”