Rockets are conceptually rather simple: you put the pointy bit upwards and make sure that the bit that will go flamey points downwards before starting the engine(s). Yet how to start each rocket engine type in a way that’s both safe and effective? Unlike in the Wile E. Coyote cartoons, real-life rocket engines do not have a fuse you light up before dashing off to a safe distance. Rather they use increasingly more complicated methods, which depend on the engine type and fuels used. In a recent article written by [Trevor Sesnic] with accompanying video featuring everyone’s favorite Everyday Astronaut [Tim Dodd], we’re taken through the intricacies of how flamey ends are made. Continue reading “The Intricacies Of Starting A Rocket Engine”→
[Joe] at BPS.space has a thing for rockets, and his latest quest is to build a rocket that will cross the Kármán Line and launch into the Final Frontier. And being the owner of a YouTube channel, he wants to have excellent on-board video that he can share. The trouble? Spinning. A spinning rocket is a stable rocket, especially as altitude increases. So how would [Joe] get stable video from a rocket spinning at several hundred degrees per second? That’s the question being addressed in the video below the break.
The de-spun video looks quite good
Rather than use processing power to stabilize video digitally, [Joe] decided to take a different approach: Cancelling out the spin with a motor, essentially making a camera-wielding reaction wheel that would stay oriented in one direction, no matter how fast the rocket itself is spinning.
Did it work? Yes… and no. The design was intended to be a proof of concept, and in that sense there was a lot of success and some excellent video was taken. But as with many proof of concept prototypes, the spinning camera module has a lot of room for improvement. [Joe] goes into some details about the changes he’ll be making for revision 2, including a different motor and some software improvements. We certainly look forward to seeing the progress!
To get a better idea of the problem that [Joe] is trying to solve, check out this 360 degree rocket cam that we featured a few years ago.
When it comes to high-powered rocketry, [BPS.space] has the unique distinction of being the first to propulsively land a solid-fueled model rocket. How could he top that? Well, we’re talking about actual rocket science here, and the only way is up! All the way up to the Kármán line: 100 km. How’s he going to get there? That’s the subject of the video below the break.
Getting to space is notoriously difficult because it’s impossible to fully test for the environment in which a rocket will be flying. But there is quite a lot that can be tested, and those tests are the purpose of a rocket that [Joe] at [BPS.space] calls Avalanche. Starting with a known, simple design as a test bed, numerous launches are planned in order to iterate quickly through several launches- three of which are covered just in this video.
The goal with Avalanche isn’t to get to the Kármán line, but to learn the lessons needed to build a far bigger rocket that will. A home-brewed guidance system, a gimballed spin-stabilized 4K camera, and the descent system are among those being tested and perfected.
Of course, you don’t have to be a rocket scientist to have fun with prototyping. Sometimes you just want to 3D print a detonation engine, no matter how long it won’t last. Why not?
[T-Zero Systems] has been working on his model Falcon 9 rocket for a while now. It’s an impressive model, complete with thrust vectoring, a microcontroller which follows a predetermined flight plan, a working launch pad, and even legs to attempt vertical landings. During his first tests of his model, though, there were some issues with the control system software that he wrote so he’s back with a new system that borrows software from the Space Shuttle.
The first problem to solve is gimbal lock, a problem that arises when two axes of rotation line up during flight, causing erratic motion. This is especially difficult because this model has no ability to control roll. Solving this using quaternion instead of Euler angles involves a lot of math, provided by libraries developed for use on the Space Shuttle, but with the extra efficiency improvements the new software runs at a much faster rate than it did previously. Unfortunately, the new software had a bug which prevented the parachute from opening, which wasn’t discovered until after launch.
There’s a lot going on in this build behind-the-scenes, too, like the test rocket motor used for testing the control system, which is actually two counter-rotating propellers that can be used to model the thrust of a motor without actually lighting anything on fire. There’s also a separate video describing a test method which validates new hardware with data from prior launches. And, if you want to take your model rocketry further in a different direction, it’s always possible to make your own fuel as well.
Every once in a while, we here at Hackaday stumble across something that doesn’t quite fit in with all the other amazing hacks we feature, but still seems like something that our dear readers need to see as soon as possible. This video of homemade rockets in Thailand is one of those things.
It comes to us from our friend [Leo Fernekes], who documents a form of amateur rocketry that makes the Estes rockets of our youth look pretty tame. It’s far easier to watch than it is to describe, but for a quick summary, the rockets are bamboo rings with a steel pipe across the diameter. The pipe is packed with homemade gunpowder and provided with nozzles that create both thrust and rotation. When ignited by torches touched to seriously sketchy primers, the rocket starts to spin up, eventually rising off the launch pad and screwing itself into the sky on a twisting column of gray smoke.
At three or four meters across, these are not small vehicles. Rather than letting a steel pipe plummet back to Earth from what looks like several hundred meters altitude, the rocketeers have devised a clever recovery system that deploys a parachute when the rocket motor finally melts through some plastic straps. The use of banana tree bark as a heat shield to protect the parachute is simple but effective; which is really the way you can describe the whole enterprise. [Leo] has another way to describe it: “Dangerously negligent madness,” with all due respect and affection, of course. It looks like a big deal, too — the air is obviously filled with the spirit of competition, not to mention the rotten-egg stench of gunpowder.
Should you try this at home? Probably not — we can think of dozens of reasons why this is a bad idea. Still, it’s amazing to watch, and seeing how much altitude these cobbled-up rockets manage to gain is truly amazing. Hats off to [Leo] for finding this for us.
Russia’s loose cannon of a space boss is sending mixed messages about the future of the International Space Station. Among the conflicting statements from Director-General Dmitry Rogozin, the Roscosmos version of Eric Cartman, is that “the decision has been made” to pull out of the ISS over international sanctions on Russia thanks to its war on Ukraine. But exactly when would this happen? Good question. Rogozin said the agency would honor its commitment to give a year’s notice before pulling out, which based on the current 2024 end-of-mission projections, means we might hear something definitive sometime next year. Then again, Rogozin also said last week that Roscosmos would be testing a one-orbit rendezvous technique with the ISS in 2023 or 2024; it currently takes a Soyuz about four orbits to catch up to the ISS. So which is it? Your guess is as good as anyones at this point.
At what point does falsifying test data on your products stop being a “pattern of malfeasance” and become just the company culture? Apparently, something other than the 40 years that Mitsubishi Electric has allegedly been doctoring test results on some of their transformers. The company has confessed to the testing issue, and also to “improper design” of the transformers, going back to the 1980s and covering about 40% of the roughly 8,400 transformers it made and shipped worldwide. The tests that were falsified were to see if the transformers could hold up thermally and withstand overvoltage conditions. The good news is, unless you’re a power systems engineer, these aren’t transformers you’d use in any of your designs — they’re multi-ton, multi-story beasts that run the grid. The bad news is, they’re the kind of transformers used to run the grid, so nobody’s stuff will work if one of these fails. There’s no indication whether any of the sketchy units have failed, but the company is “considering” contacting owners and making any repairs that are necessary.
For your viewing pleasure, you might want to catch the upcoming documentary series called “A League of Extraordinary Makers.” The five-part series seeks to explain the maker movement to the world, and features quite a few of the luminaries of our culture, including Anouk Wipprecht, Bunnie Huang, Jimmy DiResta, and the gang at Makers Asylum in Mumbai, which we assume would include Anool Mahidharia. It looks like the series will focus on the real-world impact of hacking, like the oxygen concentrators hacked up by Makers Asylum for COVID-19 response, and the influence the movement has had on the wider culture. Judging by the trailer below, it looks pretty interesting. Seems like it’ll be released on YouTube as well as other channels this weekend, so check it out.
But, if you’re looking for something to watch that doesn’t require as much commitment, you might want to check out this look at the crawler-transporter that NASA uses to move rockets to the launch pad. We’ve all probably seen these massive beasts before, moving at a snail’s pace along a gravel path with a couple of billion dollars worth of rocket stacked up and teetering precariously on top. What’s really cool is that these things are about as old as the Space Race itself, and still going strong. We suppose it’s easier to make a vehicle last almost 60 years when you only ever drive it at half a normal walking speed.
And finally, if you’re wondering what your outdoor cat gets up to when you’re not around — actually, strike that; it’s usually pretty obvious what they’ve been up to by the “presents” they bring home to you. But if you’re curious about the impact your murder floof is having on the local ecosystem, this Norwegian study of the “catscape” should be right up your alley. They GPS-tagged 92 outdoor cats — which they dryly but hilariously describe as “non-feral and food-subsidized” — and created maps of both the ranges of individual animals, plus a “population-level utilization distribution,” which we think is a euphemism for “kill zone.” Surprisingly, the population studied spent almost 80% of their time within 50 meters of home, which makes sense — after all, they know where those food subsidies are coming from.
For decades, mankind was content to launch payloads into orbit and then watch hundreds of thousands of hours of blood sweat and tears just crash into the ocean. Then, partially because of huge advancements in being able to throttle rocket engines, we started landing our first stage boosters. [Joe] over at the BPS.space YouTube channel is tired of watching SpaceX have all the booster landing fun, but he’s not quite at the throttled liquid engine stage yet. So in the video below the break he asked the question: Can you throttle solid rocket motors? Yes. No. Sort of.
Throttling liquid rocket engines is actually not that different from throttling any other engine- by limiting the amount of fuel and oxidizer. This is challenging all on its own because well… it’s rocket science. With liquid rocket engines though, the concept is at least straightforward. But model rocketry hobbyists only use liquid fueled engines on the extreme high end. The vast majority instead use solid fueled rockets where the fuel is pre-mixed and isn’t variable at all.
These obvious hurdles didn’t stop [Joe] from trying. And trying again. Then, again. And once more for good measure. And then again for repeatability. There are definitely some failures along the way, and we applaud [Joe] for even admitting that he didn’t know how to use a drill properly. Hackers of any age can relate to the time when the didn’t know how to do something, although we also tend to not talk about that part too much.
We won’t spoil the ending except to say that the video is definitely worth a watch to see how [Joe] essentially solves the problem of limiting the effective thrust of a solid rocket engine without actually throttling the engine, and learns about a new issue he’d never seen before.
