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SpinLaunch is building a centrifuge to launch satellites into orbit

wired.com

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Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#91

Post by viraptor »

mlindner wrote: post #67
NikolaeVarius wrote: post #7

Earlier quoted context omitted.

Wut? Their goal is to allow the rocket to ignite at 200k ft. Thats only a bit lower than the altitude SpaceX ignites its second stage, which is not reusable

The problem isn't altitude, it's speed. Launching from the air has all the same problems of air launched rockets from planes. Except now they're trying to sling a massive rocket up to 200k feet along with all the sloshy liquids inside without anything breaking. It's complete and utter madness. The founders/investors are guaranteed to lose all their investments.

I get the scepticism, but you're not really supporting your opinions here. The first rocket was madness, the shuttle was madness, landing rockets on sea platform was madness. Sometimes mad ideas work. You'll need more details to guarantee something.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#92

Post by Aeolun »

WJW wrote: post #80
martey wrote: post #46

The Wired article that this SyFy blurb is based on has more details (and more criticism) - https://www.wired.com/story/inside-spinlaunch-the-space-indu... > One former employee, who spoke on condition of anonymity due to their nondisparagement and nondisclosure contracts, acknowledged the gulf between theory and reality. They described SpinLaunch’s prototype centrifuge as a relatively unsophisticated machine that “an…

This quote is a gem too: > We’ve been putting together a team of engineers who, for the most part, are too young to say SpinLaunch couldn't work.

A fair strategy, but not one that inspires a lot of confidence.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#93

Post by mhandley »

I couldn't help wondering what happens to the counterweight. 100kg travelling at 5000mph works out as about 500MJ. For comparison, 1 tonne of TNT is about 4.2GJ, so the energy of the counterweight is about the same as 120kg of TNT. Looks like stopping the counterweight will produce a pretty big explosion, but probably not their biggest problem.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#94

Post by viraptor »

WJW wrote: post #73
mlindner wrote: post #64

Earlier quoted context omitted.

The forces are going even higher than that. 10,000g is what you get from launching out of high explosive powered military cannon. The US military has managed to put guided rounds in such cannons, but they certainly aren't getting you to space with such a cannon. You need much higher than 10,000g to get up to that kind of speed.

Technically it's more the time that the acceleration is applied for, but I see what you mean. I used to work as a weapons engineer for the Dutch navy and they were quite involved at getting the Vulcano ( https://www.leonardocompany.com/en/products/vulcano-155mm ) rounds working at the time. IIRC the larger caliber rounds were subjected to about 40.000g at peak acceleration though you could vary the amount of powder s…

Do you know if that was fully custom hardware? Or what I'm specifically asking is: was the problem that the available hardware is not produced to withstand 40kG, or that they can't produce hardware able to withstand it? Because there latter sounds like a serious problem, but the former sounds like it could be solved with money spent on it.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#95

Post by pjc50 »

absolutelyrad wrote: post #90
londons_explore wrote: post #88

Earlier quoted context omitted.

Assume the screen and top glass of an iPhone are 40 grams. 10000g's will make the effective mass of them 400kg. Could an iPhone survive 400kg sitting on top of it? It's definitely within the realm of possibility...

The force is acting on internal parts too. I don't think the silicon microchip inside can survive those forces. There is just too much that could go wrong here. I would be positively shocked if this thing works. I'd have to rethink a lot of things I hold an opinion on.

The microchip can definitely survive. I'd be worried about the MEMS accelerometer and microphones, though. I would have assumed the glass itself was the biggest risk, but if the phone is "full" enough of stuff that there's nowhere for it to bend internally then it could be surprisingly durable.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#96

Post by noitpmeder »

mhandley wrote: post #93

I couldn't help wondering what happens to the counterweight. 100kg travelling at 5000mph works out as about 500MJ. For comparison, 1 tonne of TNT is about 4.2GJ, so the energy of the counterweight is about the same as 120kg of TNT. Looks like stopping the counterweight will produce a pretty big explosion, but probably not their biggest problem.

From the article

"a counterbalance spinning opposite the rocket gets released at the same time, preventing the tether from becoming unbalanced and vibrating into oblivion"

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#97

Post by Havoc »

Cthulhu_ wrote: post #58
blackrock wrote: post #49

Earlier quoted context omitted.

Raw metal powder for 3D printing laser sintering. Or plastic pellets. Water. Fuel. Clothes. Maybe this is what can kick start the 3D printing in space revolution. Maybe it can also launch radioactive waste into space? One bucket at a time. Then a space towtruck can be launched to hurl it into the sun. But it’ll likely just part a naive investor from their money.

Not sure how serious you are with the radioactive waste thing but I'll do the HN thing and bite (nerdsnipe!), because that's not going to work. You can't launch things into the sun, you need to decelerate objects. The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. And orbiting radioactive waste is just asking for trouble. The total amount of radioactive w…

>The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way.

Surely you’d just need enough to end up in a decaying orbit? Then it’ll eventually reach the sun

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#98

Post by WJW »

viraptor wrote: post #94
WJW wrote: post #73

Earlier quoted context omitted.

Technically it's more the time that the acceleration is applied for, but I see what you mean. I used to work as a weapons engineer for the Dutch navy and they were quite involved at getting the Vulcano ( https://www.leonardocompany.com/en/products/vulcano-155mm ) rounds working at the time. IIRC the larger caliber rounds were subjected to about 40.000g at peak acceleration though you could vary the amount of powder s…

Do you know if that was fully custom hardware? Or what I'm specifically asking is: was the problem that the available hardware is not produced to withstand 40kG, or that they can't produce hardware able to withstand it? Because there latter sounds like a serious problem, but the former sounds like it could be solved with money spent on it.

For cost purposes they started out with mostly off-the-shelf components and then they slowly replaced those components that could not withstand the stress with custom kit. IIRC just casting some components in sturdy resin was often enough. Bad for the thermals ofc, but it only needed to run for a few minutes anyway. I left the navy a few years ago but since the product is now apparently ready I assume that they managed to solve all remaining problems. (Acquiring a GPS signal quickly enough from a high speed projectile was not trivial either)

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#99

Post by mrfusion »

mhandley wrote: post #93

I couldn't help wondering what happens to the counterweight. 100kg travelling at 5000mph works out as about 500MJ. For comparison, 1 tonne of TNT is about 4.2GJ, so the energy of the counterweight is about the same as 120kg of TNT. Looks like stopping the counterweight will produce a pretty big explosion, but probably not their biggest problem.

Can it regenerate energy when slowing down?

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#100

Post by marsokod »

mlindner wrote: post #76
WJW wrote: post #73

Earlier quoted context omitted.

Technically it's more the time that the acceleration is applied for, but I see what you mean. I used to work as a weapons engineer for the Dutch navy and they were quite involved at getting the Vulcano ( https://www.leonardocompany.com/en/products/vulcano-155mm ) rounds working at the time. IIRC the larger caliber rounds were subjected to about 40.000g at peak acceleration though you could vary the amount of powder s…

They apparently tested spinning everyday objects up to 10,000g, which is great, but I wonder if they thought about bending moments induced when the thing is suddenly released.

And the mechanical and thermal shocks it gets when it passes from the vacuum chamber to the atmosphere.

IMHO the centrifuge part is the easiest of their challenges.

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