00:40:55 · Molly O'Shea, Philip Johnston
[00:40:55] S0: Science. So, Philip, we're back at the vibe table, and we're about to do some testing. Do you wanna explain this? [00:41:02] S1: Yeah. So we need to simulate the launch environment. And so in order for SpaceX to allow us to launch on a rocket with multiple tenets, they wanna make sure that both nothing's gonna fly off from any individual satellite in in launch, but also, they don't want any satellite to resonate at a certain frequency, throws the whole stack off. And so the point of the bike table is to put the satellite through every different frequency and amplitude that the satellite is gonna experience during launch and also this shock test so that we make sure nothing flies off, we also make sure that we don't have resonance at a certain frequency. [00:41:38] S0: How long do you run it for? [00:41:39] S1: It depends on the test, but the launch environment itself is about seven minutes, and so there are some tests we would run for a few minutes. Most tests we run for a shorter period, especially what they call the sort of... Yeah, like, random vibe we run a bit longer, but there is the shock test we run for shorter. [00:41:58] S0: Have you ever [00:42:00] S1: Sat on a vital on that? I have never sat on that, I have to say. [00:42:06] S0: Had to ask. [00:42:07] S1: I've [00:42:09] S0: touched them before, but [00:42:10] S1: Oh, yeah.
00:42:10 · Philip Johnston, Molly O'Shea
[00:42:10] S1: Oh, yeah. [00:42:12] S0: Were at Zipline, and we went into their testing room, and they had a vibe table and these like RC propeller, like RC fans to test the drones with and they would fly them in front of it and see if anything would, you know, be fragile or break, if there were any like fractures. [00:42:32] S1: And it ended up just being me walking through Farcey Man's No way. [00:42:37] S0: Which is... They're... I think they go, like, 80 miles an hour. [00:42:40] S1: Wow. Yeah. Crazy. Oh, there you go. Oh. So this is a very low frequency test. We're doing it as low frequency mainly so that you can see what it looks like when it moves. But the... When when it moves faster, basically, you won't be able to see it moving. That's... They're moving at least 50 hertz, so 50 times back and forth per second. And this is basically a huge solenoid, so a huge mag... Magnet that's pulling this thing in and out. It's, yeah, basically speeding up now. So we walk in? Yeah. Yeah. We're good.
00:42:40 · Philip Johnston, Ezra Feilden, Molly O'Shea
[00:42:40] S1: Wow. Yeah. Crazy. Oh, there you go. Oh. So this is a very low frequency test. We're doing it as low frequency mainly so that you can see what it looks like when it moves. But the... When when it moves faster, basically, you won't be able to see it moving. That's... They're moving at least 50 hertz, so 50 times back and forth per second. And this is basically a huge solenoid, so a huge mag... Magnet that's pulling this thing in and out. It's, yeah, basically speeding up now. So we walk in? Yeah. Yeah. We're good. [00:43:22] S2: So the hardware we have on the table at the moment is part of our thermal management system called the accumulator. So as the... So we have liquid cooling on Starcloud two and all of our future vehicles. As the liquid heats up, it wants to expand, and so you have to have a component which allows that expansion to take place. Otherwise, you'll burst your your cooling system. So that's what the accumulator does. It's... It allows for that thermal expansion of the fluid to to manage the pressure inside the the cooling system. And that's what we have on the table right now is our... The accumulator for Starcloud two. Yep. We get... Yeah. Go for it. [00:44:03] S1: Yeah. There you go. So... [00:44:13] S0: Oh my god.
00:44:13 · Molly O'Shea, Philip Johnston
[00:44:13] S0: Oh my god. [00:44:14] S1: Right. Crush crazy. Yeah. So this is... Right now, the test is doing is what's called a sign sweep. It's where we're gonna go through every different frequency and amplitude that the satellite will experience during launch. It starts very low frequency. We're doing this low frequency. Normally, wouldn't even start this low, but we wanted to be able to see that it's moving here. As it gets faster and faster, it it... You won't really be able to see the moving of it. [00:44:44] S0: What is the worst thing that a vibe table has done? [00:44:49] S1: The worst thing that a vibe table... [00:44:50] S0: Well, has a vibe table, like, ever... Like, is a magnet, like, shot out or anything? [00:44:56] S1: No. The the actual vibe tables themselves are pretty safe. The worst thing that can happen with a vibe table is whatever you're testing can explode. So for example, underneath Starcloud two, we have this xenon tank for the thrusters, And if the xenon tank explodes, it's about half the explosive power of a hand grenade. [00:45:18] S0: Great. That's awesome. That's really good to know. [00:45:21] S1: Yeah. Okay. That's why we're not doing that test today. So [00:45:23] S0: Yeah. So does everyone leave the building when you test that?
00:45:23 · Molly O'Shea, Philip Johnston
[00:45:23] S0: Yeah. So does everyone leave the building when you test that? [00:45:26] S1: Literally, everybody leaves the building. So we had... We put this entire satellite on this. By the way, you can see it's in two axes. So the solenoid actually can flip up, and we can test it like this so that we can test in different axes. But yeah, when we fly that test up, have to... Everybody has to leave the building. [00:45:44] S0: I doubt the toy manufacturer that has storage across the street has any idea what's going on in here. [00:45:51] S1: They have no idea. But they are far enough away that we know that they're Yeah. Like, [00:46:01] S0: why is everyone running out? [00:46:04] S1: Yeah yeah that's first mode. Oh okay so what they're testing for is this first mode it's the first frequency at which it's resonating and when you can hear it making this clicking sound that means we've hit the the first mode of of this thing here. What the... What SpaceX requires is that you don't have a first mode below a certain frequency. I think it's around 40 hertz. Okay. So it cannot resonate at anything less than 40 times a second. And the reason for that is, let's say it would resonate at, like, twice a second, then the whole thing's gonna go like this back and forth. Yeah. And that will move all the other payloads in the stack. [00:46:45] S0: That's a really good point. So what is the process to get your space prop or any any kind of components up into space tested to make sure that it's, like, viable for Falcon nine or Starship?
00:46:45 · Molly O'Shea, Philip Johnston
[00:46:45] S0: That's a really good point. So what is the process to get your space prop or any any kind of components up into space tested to make sure that it's, like, viable for Falcon nine or Starship? [00:46:58] S1: Yeah. So as we mentioned, booking is just put your credit card down, but then that kicks off a whole long process where both regulatory, we have to file with the FCC for the orbit and for the spectrum we're gonna use, and we have to have a deorbit procedure and all of these kinds of things. And then SpaceX has a whole laundry list of requirements, mainly, to be honest, to make sure that your spacecraft isn't gonna destroy any other spacecraft on the stack. So if you book a fully dedicated Falcon nine, the requirements are less stringent than if you're booking a rideshare because they need to make sure you're not gonna move the whole stack or you're not gonna have things flying off and killing other spacecraft. [00:47:34] S0: Damn. Yeah. So how do they actually verify your approvals? [00:47:41] S1: So we have to do vive and then we send them the vive reports after we've done the vive testing. [00:47:46] S0: Has anybody ever [00:47:49] S1: lied? I don't think so. Would be quite hard to lie. I mean reproducing these vibe reports would be quite a challenge. I don't [00:47:58] S0: know why you would do that unless you're an op. [00:48:01] S1: Unless you're an op. [00:48:01] S0: Unless you're an op. [00:48:03] S1: There you go.