Picture of self landing drone satellite with orange and black body. Propellors are extended.

FPV Drone Takes Off From A Rocketing Start

May 15, 2025 by Ian Bos 24 Comments

Launching rockets into the sky can be a thrill, but why not make the fall just as interesting? That is exactly what [I Build Stuff] thought when attempting to build a self-landing payload. The idea is to release a can sized “satellite” from a rocket at an altitude upwards of 1 km, which will then fly back down to the launch point.

The device itself is a first-person view (FPV) drone running the popular Betaflight firmware. With arms that swing out with some of the smallest brushless motors you’ve ever seen (albeit not the smallest motor), the satellite is surprisingly capable. Unfortunately due to concerns over the legality of an autonomous payload, the drone is human controlled on the descent.

Using collaborated efforts, a successful launch was flown with the satellite making it to the ground unharmed, at least for the most part. While the device did show capabilities of being able to fly back, human error led to a manual recovery. Of course, this is far from the only rocketry hack we have seen here at Hackaday. If you are more into making the flight itself interesting, here is a record breaking one from USC students.

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Open Source Liquid Rocket Reaches For The Sky

August 20, 2024 by Tom Nardi 30 Comments

Since the very beginning, solid-propellants have been the cornerstone of amateur rocketry. From the little Estes rocket picked up from the toy store, to vehicles like the University of Southern California’s Traveler IV that (probably) crossed the Kármán line in 2019, a rapidly burning chunk of solid propellant is responsible for pushing them skyward. That’s not to say that amateur rockets powered by liquid propellants are completely unheard of … it’s just that getting them right is so ridiculously difficult that comparatively few have been built.

But thanks to [Half Cat Rocketry], we may start to see more hobbyists and students taking on the challenge. Their Mojave Sphinx liquid-fueled rocket is not only designed to be as easy and cheap to build as possible, but it’s been released as open source so that others can replicate it. All of the 2D and 3D CAD files have been made available under the GPLv3 license, and if you’re in the mood for a little light reading, there’s a nearly 370 page guidebook you can download that covers building and launching the rocket.

Now of course we’re still talking about literal rocket science here, so while we don’t doubt a sufficiently motivated individual could put one of these together on their own, you’ll probably want to gather up a couple friends and have a well-stocked makerspace to operate out of. All told, [Half Cat] estimates you should be able to build a Mojave Sphinx for less than $2,000 USD, but that assumes everything is done in-house and you don’t contract out any of the machining.

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The Amateur Rocketry Hack Chat Reaches For The Stars

December 2, 2022 by Tom Nardi 7 Comments

Hackaday has been around long enough to see incredible changes in what’s possible at the hobbyist level. The tools, techniques, and materials available today border on science-fiction compared to what the average individual had access to even just a decade ago. On a day to day basis, that’s manifested itself as increasingly elaborate electronic projects that in many cases bear little resemblance to the cobbled together gadgets which graced these pages in the early 2000s.

But these gains aren’t limited to our normal niche — hobbyists of all walks have been pushing their respective envelopes. Take for example the successful launch of MESOS, a homebuilt reusable multi-stage rocket, to the very edge of the Kármán line. It was designed and built by amateur rocket enthusiast Kip Daugirdas over the course of several years, and if all goes to plan, will take flight once again this summer with improved hardware that just might help it cross the internationally recognized 100 kilometer boundary that marks the edge of space.

We were fortunate enough to have Kip stop by the Hack Chat this week to talk all things rocketry, and the result was a predictably lively conversation. Many in our community have a fascination with spaceflight, and even though MESOS might not technically have made it that far yet (there’s some debate depending on who’s definition you want to use), it’s certainly close enough to get our imaginations running wild.

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Student-Built Rocket Engine Packs A Punch

October 24, 2019 by Bryan Cockfield 30 Comments

A group of students at Boston University recently made a successful test of a powerful rocket engine intended for 100km suborbital flights. Known as the Iron Lotus (although made out of mild steel rather than iron), this test allowed them to perfect the timing and perfect their engine design (also posted to Reddit) which they hope will eventually make them the first collegiate group to send a rocket to space.

Unlike solid rocket fuel designs, this engine is powered by liquid fuel which comes with a ton of challenges to overcome. It is a pressure-fed engine design which involves a pressurized unreactive gas forcing the propellants, in this case isopropanol and N2O, into the combustion chamber. The team used this design to produce 2,553 lb*ft of thrust during this test, which seems to be enough to make this a class P rocket motor. For scale, the highest class in use by amateurs is class S. Their test used mild steel rather than stainless to keep the costs down, but they plan to use a more durable material in the final product.

The Boston University Rocket Propulsion Group is an interesting student organization to keep an eye on. By any stretch of the imagination they are well on their way to getting their rocket design to fly into space. Be sure to check out their other projects as well, and if you’re into amateur rocketry in general there are a lot of interesting things you can do even with class A motors.

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DIY Falcon Heavy 2nd stage test flight of BPS.space

Rocket Science With The Other SpaceX

September 18, 2018 by Steven Dufresne 29 Comments

When you say that something’s not rocket science you mean that it’s not as hard to understand or do as it may seem. The implication is that rocket science is something which is hard and best left to the likes of SpaceX or NASA. But that’s not the hacker spirit.

[Joe Barnard] recently had an unsuccessful flight of his Falcon Heavy’s second stage and gives a very clear explanation of what went wrong using those two simple concepts along with the thrust, which in this case is just the force applied to the moment arm.

And no, you didn’t miss a big happening with SpaceX. His Falcon Heavy is a homebrew one using model rocket solid boosters. Mind you, it is a little more advanced than that as he’s implemented thrust vectoring by controlling the engine’s direction using servo motors.

And therein lies the problem. The second stage’s inertia is so small and the moment arm so short that even a small misalignment in the thrust vectoring results in a big effect on the moment arm causing the vehicle to deviate from the desired path. You can see this in the first video below. Another issue he discusses is the high drag, but we’ll leave that to the second video below which contains his explanation and some chart analysis.

So yeah, maybe rocket science is rocket science. But there’s no better way to get your feet wet then to get out there and get building.

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Building Homebrew VTOL Rockets

February 16, 2017 by Brian Benchoff 35 Comments

No one can deny what SpaceX and Blue Origin are doing is a feat of technological wizardry. Building a rocket that takes off vertically, goes into space, and lands back on the pad is an astonishing technical achievement that is literally rocket science. However, both SpaceX and Blue Origin have a few things going for them. They have money, first of all. They’re building big rockets, so there’s a nice mass to thrust cube law efficiency bump. They’re using liquid fueled engines that can be throttled.

[Joe Barnard] isn’t working with the same constraints SpaceX and Blue Origin have. He’s still building a rocket that can take off and land vertically, but he’s doing it the hard way. He’s building VTOL model rockets. Most of the parts are 3D printed. And he’s using solid motors you can buy at a hobby shop. This is the hard way of doing things, and [Joe] is seeing some limited success with his designs.

While the rockets coming out of Barnard Propulsion Systems look like models of SpaceX’s test vehicles, there’s a lot more here than looks. [Joe] is using a thrust vectoring system — basically mounting the Estes motor in a gimbal attached to a pair of servos. This allows the rockets to fly straight up without fins or even the launch rod used to get the rocket up to speed in the first few millseconds of flight. This is active stabilization of a model rocket, with the inevitable comments of ITAR violations following soon afterward.

Taking off vertically is one thing, but [Joe] is also trying to land his rockets vertically. Each rocket he’s built has a second Estes motor used only for landing. During descent, the onboard microcontroller calculates the speed, altitude, and determines if it’s safe to attempt a vertical landing. If the second motor has sufficient impulse to make velocity and altitude equal zero at the same time, the landing legs deploy and the rocket hopefully makes a soft touchdown in the grass.

While [Joe] hasn’t quite managed to pull off a vertical takeoff and landing with black powder motors quite yet, he’s documenting and livestreaming all of his attempts. You can check out the latest one from a week ago below.

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Serial Telemetry To Wi-Fi With An ESP8266

March 4, 2016 by Jenny List 12 Comments

Hackaday.io user [J. M. Hopkins] had a problem with his rocketry. Telemetry from the rockets came down to Earth via a 433MHz serial link, but picking just the bits he needed from a sea of data for later analysis on a laptop screen on bright sunny days was getting a little difficult.

His solution was to bring the serial data from his transceiver module to an ESP8266, and from that both share it over WiFi and display pertinent information via I2C to an LCD for easy reference. And he’s put the whole lot with a power supply in a rather splendid wooden case with an SMA socket on the back to attach his Yagi.

All information received from the telemetry is passed to a client connecting via Telnet over the WiFi, but pertinent information for the LCD is selected by sending it from the rocket enclosed in square brackets. We hope that the source code will be forthcoming in time.

This isn’t the first time we’ve featured rocket telemetry here at Hackaday. And we’d be missing a trick if we didn’t point out that this project is using our own Hackaday-branded Huzzah ESP8266 breakout board from the Hackaday Store.