- The centrifuge ran at 20% of its maximum power, he said. He declined to give specific details about the projectile’s flight, but said it flew at supersonic speeds and reached altitudes of “tens of thousands of feet.” The projectile was instrumented and collected data, but did not have any active controls, instead flying a ballistic trajectory.
Previously:
I wish I could have conducted that class.
I love that pinned comment so, so much. Started the video at a random spot, and within 15 seconds "... as the vehicle is released, using a secret release mechanism that SpinLaunch hid from our cameras... ". Thought I could resist watching, not so sure, now.
I was in my kitchen heating up some leftovers, and yelling at my wife "NO, BUT THIS IS CONTENT ESPECIALLY FOR ME". You will only regret about 10 minutes of those 42, when they run through some formulaic plug-n-chugs. And those segments have better educational visuals than NASA, e-texts, y'know, almost anything. Fuckin' timeline.
I've thought about this more. I can't come up with a better scheme to fuck over unworthy venture capitalists. I am pro SpinLaunch. Elizabeth Theranos is also great. Just don't get caught. Hey Devac, what/how do you want to do/scam?
That's a tad blatant steal, but sure. OK, so we all know spinning is a good trick. Anakin does it, LHC does it, SpinLaunch does it. But that's their folly: too many moving parts! Imagine this, a revolution in the field of ballistic coming in a shape of a cylinder under vacuum. "How does it move the object?" you ask? Easy. Forget of the by-gone era of complex rotor with(out) a counter-balance or chemical propellant. It'll utilize the tremendous power hidden in a svelte form factor of a cranked-up spring. That's right, only TWO moving parts: crank and trigger. And here's the opportunity for synergy™: Elon Musk already works on vacuum tubes with carts in them, all we need is convince him to forget about that silly electrical automobile gizmo and finance our Spring Theory research. BTW, my working name for the device would be The Tosser™.I can't come up with a better scheme to fuck over unworthy venture capitalists.
Hey Devac, what/how do you want to do/scam?
Needs: - Blockchain - IoT - RMR - Leasebacks We're gonna call the company KNsys which we will require everyone to pronounce "kinesis." Our logistics will all exist on a Solidity/Rust hybrid chain powered by KNE, or "Knee" tokens that are L2 ZK rollups for no good reason. Owners of KNE will finance Tosser™s and get to see their utilization - there are only so many Tosser™s in existence at any given time which means as they wear down the opportunity to build new ones helps drive scarcity and investment in a virtuous cycle. The position of any Tosser™anywhere in the logistics cycle will be determined by triangulation on the Helium Network because of course it will be.
I had to look stuff up, slap myself awake reading WTF leaseback or RMR are, and felt genuine regret for writing my shitty pitch. So, you wanna do sales and marketing? Right now, we can pay with the most precious resources in the known universe: exposure and meatbread.
Unfortunately for us, my friend, neither of us are the children of Enron VPs and thus we are unlikely to get to pitch this to anyone with money. On the plus side, we may be leaving the era of stupid money behind for a time. I remember when "let's sell pet food UPS" went from world's best idea to world's worst idea in the turn of a NASDAQ; back then you still had to pay workers so our internet serfdom wasn't yet inevitable. But even now, the "let's buy scooters for $150, rent them for 10 cents a mile, trash them after two weeks and expect to turn a profit" company is eating shit, the "let's sell a $200 exercise bike with a $100 tablet for $2500 so we can charge people $80 a month for videos" company is down 84% from its ATH and the "let's do an end-run around the listing process so we can skin the rubes more easily" movement is running out of steam. Things will get stupid again. So much stupider that a spring-launched orbital payload company will get money. Until then, we'll have to settle for shitty post cards.
This is all fine by me. I hereby notarize your comments. We now have a legal team, and I hav- leans in and whispers They say we don't have to pay the workers (who will be in charge of spring compression) a living wage if we plan to kill them, but we just can't let anyone know that we knew about the very high likelihood (100%, in fact) of killings. I thought about using robots or something for the crankening, but a large team of children jumping up and down on the spring turns out to be better for the bottom line. COUGH Anyway. Phase II will be asteroids, to mine rare Earth metals. And India is the perfect asteroid-catching shape! We will not feel the shockwave deep down in our tunnels, with enough workers working the entrances. The problem is that after we scoop up the metals, the market may not be good for it. I've got analysts projecting that people will be much more valuing stupid shit like food and water after the asteroid hits. That's OK, because we've built the option to short company shares into our contracts. Someone left alive will buy them, we've already begun the PR work to ensure. It's possible we will do some healthy, forced insemination to drive the annual growth needed after the asteroid thing, because Phase III is pretty ambitious. Did you know that there are no markets yet in neighboring star systems? If we get there first, we could plant the company flag and really corner demand, I think. Dear Christ Almighty, we are smart! We earned this. 😎 Keep up all the hard work, Devac!!
I don't know how you can say that when I haven't outlined the ways we're going to be doing sexism yet. No women. Absolutely ZERO women, and I mean everywhere. We will have synthetic reproduction. This has become The Phase 0.0 "OPERATION NOW" target for our company. We expect to make and distribute at least ten thousand synth reproduction units, but perhaps as many as ten billion. This company policy WILL be attacked by feminists, who are selfishly only trying to not die. It turns out (I just had another team tell me this, correction from Elon Musk) there is a resource shortage, and it's better if US Boys (this company name is polling) just kinda take the helm and the resources, like we have been, but even more now. So and I guess my main point is that I'm not sure why this sort of thing can't go forward? The business model is the only business ever modeled. Our company isn't going to bore people with academic posturing, and so I didn't bother reading your other post with the technical discussion of spinning. Jobs! There will be them, and for pretty much everyone alive at the time of job posting, I think, which does currently include you.
I will admit to occasionally surfing eBay for their swag. I still lament not purchasing the autographed Mars One blueprints when I had the chance, despite the fact that they were like $70. I have so much crazy insider art that if I had more wall space my universe would look like the murderer's house in CSI or some shit.
THE FORMALIZATION OF DUNKING ON SpinLaunch --- The Dribble kleinbl00: I'm now convinced the main chamber was indeed at partial pressure. Maybe like half an atmosphere or so. In the Clint Mansell soundtrack promotional vid, at 0:46 I can see some of the membrane get sucked back into the chamber faster than gravity alone would pull it downwards, but not fast enough to indicate a near-totally evacuated chamber. Any whooshing and whizzing audio was probably synthesized and added in post, I'm increasingly sure. Right, so I just did some high school math regarding a maximum apogee of "tens of thousands of feet" for a ballistic shot vertically. The upper limit, 100,000 ft., requires a release velocity of a little less than 800 m/s. Escape velocity in the absence of any atmosphere is ~11,000 m/s, so you'll need to go ehhhhhhhhh a little faster. However; good news, some of the requisite velocity is offset by the plan to put something resembling a rocket engine and its fuel up to 10k g's before lighting the fuse before the payload can fall back to Earth. Did you notice the verbiage used in the press release? Launched at "20% of the centrifuge's maximum power"? This is not really a system well-defined by its power consumption. It’s a question of release velocity and how much payload is second-stage rocket and fuel. I bet it takes a lot of power to spin anything up to a high speed in an almost-not-vacuum. v^2/r says that if you scale up the centrifuge by a factor of three, --- Juke Uh-oh --- C'mon n' Slam if You Wanna Jam The establishment rocket launch environment is pretty well-characterized. NASA has specific requirements for each launch vehicle, which are passed on to contractors. For example, mechanical engineers are given a set of vibration table testing requirements. There is no static loading requirement, only a sine sweep test to confirm and zero-in on the resonances predicted from modeling, and then a random noise test. Based on the 2,000-kg weight limit, the mass of "payload" dedicated to shielding the actual payload from introduction to a near-instantaneous shock, or damping the actual payload response from the “jerk” may be, like, almost all of the "payload". The secrets behind the stability of a missile going Mach whatever with a bomb inside of it are: 1) A gradual acceleration inside a gradually changing fluid environment (lessening atmospheric density as it goes up). 2) The direction of the axis of symmetry (where the nosecone points) is almost exactly parallel to the velocity vector, and any stabilizing spin is confined along this axis, the axis of the lowest rotational moment of inertia. 3) Everything.; Everything, including the bomb and all associated electronics inside the missile, was designed with the environment in mind. We can see for ourselves in these videos that 1) & 2) failed. For 3), I doubt that anyone who's ever made any comms, optical, EM-fields, or particle sensing instrumentation (or even spacecraft buses, whatever) could honestly tell you they could pull 10k g's static load with anything remotely similar to their current mechanical design. Solid-propellant rocket fuel? Good luck, ya got a lotta free energy floating around, hopefully it doesn’t localize into anything sparkable. — The Rebound But, OK. We might should think about payload design with a ~100 g static load (just, like, for starters) and a way wilder dynamic environment, primarily based on the shock. As Devac points out, there are potentially more realistic future applications of spin-launching in other environments, like on the moon. The entire concept isn't stupid, but SpinLaunch currently looks to me like either an intentional misrepresentation of the facts to investors or a very deep ignorance. Or a bit of both. Just my opinion.10k g's
ten thousand times one “jee"
10,000*9.8m/s^2 of static centripetal acceleration
Hopefully, for attitude control, the release is exactly instantaneous across the entire length of the payload
Hopefully, to avoid a disastrously high jerk response of the payload components, the release interval (Δt) is as large as possible
So I did some college physics. Statics'n'dynamics. Engineer stuff. It ain't hard. Let's start with a model, shall we? I'ma do that obnoxious engineering oversimplification thing where we model a horse as a sphere. I'm also going to start in Freedom Units and work backwards because ugh. So a lawn dart is about 12" long and weighs on the order of half of a pound. We're gonna simplify that into 30cm and one kilogram. We're also going to disregard the complexity of fins and non-uniform cross section and turn this thing into a highway flare, basically - let's model it as a cylinder 30cm long by 2cm in diameter. LAWN DART = 1kg, 30cm x 2cm cylinder We're going to do this because we're going to rig up a bola-thing out of jumprope and do some playground physics. Through sheer MacGyver awesomeness I'm going to craft a sling with a length of around 3 feet (1m) and I'm going to spin my lawn dart around my head at a rate of 3Hz. Once it's as fast as I can spin it (3Hz) I'm going to let go. LAWN DART ANGULAR VELOCITY = 6pi radians/sec = 1080 degrees/sec I'm then going to abuse the bejeesus out of online calculators because I'm lazy but will link them. In this case, I'm going to convert from angular velocity to linear velocity. LAWN DART LINEAR VELOCITY = 18.85 m/s Hey that's pretty good. I'ma ask my buddy Newton (Vf = Vi plus at) how long it's gonna be in the sky, assuming it goes straight up, because I'm lazy and because it's a lawn dart and that's what they're for, duh. No drag because again, lazy. LAWN DART FLIGHT TIME = 1.92 s Great now I can ask Isaac for its distance (d = v0t plus 1/2at^2). LAWN DART DISTANCE = 18.1m 59 feet straight up. Bitchin'! Definitely more than people can throw. We got a soup goin' baby! But now we gotta get Isaac to run some of the harder numbers. Like, energy. KE=1/2mv^2. LAWN DART KINETIC ENERGY (linear) = 177J ....shit. Why did the universe compel me to put a caveat on the KE? Musta been those two solid years of intro physics, followed by three solid years of engineering. Hmmm. KE = 1/2 Iomega^2. SHIT. Frickin' moments of inertia? I = L/omega. L = M x V x R. Uhhhm, M is mass is 1kg. V is angular velocity. R is radius around the centroid - hey we got all this shit! LAWN DART ANGULAR MOMENTUM = 18.85 kg/m^2 s I don't like those units. They're... foreboding. But now we can calculate the angular kinetic energy. LAWN DART KINETIC ENERGY (rotational) = 3,349J ...that is more. more energy. Uhhhhhm somehow between spinning it around our arm and launching it straight up we bled off 95% of our energy. Which, my buddy Isaac reminds me, is not permitted by the universe. So here's the basic problem: we were spinning that lawn dart around a fixed axis that happened to be "where I hold the jumprope." That lawn dart is not going to stop spinning just because we did. It's going to spin around its new system centroid. Good thing we already defined it as a road flare rather than a lawn dart 'cuz here's where stuff ceases to be fun (or starts, depending on one's perspective). Now - I did this math? I did the shit out of this math 20-f'n years ago. So here's where I start fumbling. Because what we're worried about is conservation of angular momentum. ice skater pulls their arms in, they spin faster. In fact, if you look up "discus throwing momentum" you will get like long-ass papers that are mostly speculation, a little measurement and no real answers on the "conservation of angular momentum" problem. Because really, the momentum of the system is conserved, and we've presumed our rope (and me!) has no mass. But let's fumble on and wait for Devac to poke holes in this 'cuz he's wicked smart. Anyway: angular momentum be conserved, yo. We have our kinetic energy - it's 3349 - 177 = 3.2kJ. we can calculate our new moment of inertia to be 0.007556 kg-m^2. So through sheer dumb conservation of momentum, our lawn dart is now in a 146Hz flat spin. Is it really, though? I have a degree in this shit and I'm pretty shaky on it. Turns out you physics nerds are better at this shit. Lo and behold you can't disregard half the system no matter how hard I, or Spinlaunch, wants to. But since we know even less about it than we do about the business end of the process, I'm not even going to try. I'm going to refer to that 146 Hz flat spin as the lawn dart's "suicidal urge" because while we can all agree that I'm not flippin' a lawn dart into a low thrum above my head, I think we can also agree that I'm not NOT putting a spin on it, and that when 95% of the energy is not pushing my lawn dart up, it's pushing something SOMEWHERE. Note that "suicidal urge" isn't "jerk" but they're related. The suicidal urge is what changes the lawn dart spinning around my center of mass at 3Hz to trying to spin around its own center of mass at 150. Again - don't think it's 146, certain it ain't zero. What we're looking at here, obviously, is KSP attempting to deal with corner-case physics it definitely wasn't designed for. I doubt it's got a 2-body problem algorithm in there. The launcher does not tear itself to shreds. It's got a vectoring motor capable of covering up nearly any crime. And even Kerbal is all "lol this thing is going through a full spin before we figure our shit out." LAWN DART SUICIDAL URGE = 146Hz = 3.2kJ
'Sokay. We've got a lawn dart, and it's doing more than going up. Now let's look at our friends Spinlaunch and their demo launcher. I'ma use your velocity 'cuz you calculated it and again, lazy. I'm also going to model their demo as a scuba tank because - you guessed it! - lazy. Let's go with an AL80 - 14.2kg, 184mm in diameter, 662mm long. we're going to work backwards from your linear velocity. SCUBALAUNCH = 14.2kg, 184mm dia, 662mm long SCUBALAUNCH LINEAR VELOCITY = 800m/s SCUBALAUNCH RADIUS = 1/3 45m = 15m SCUBALAUNCH ANGULAR VELOCITY = 509 RPM Oops, we already have a problem. We know it's designed to go 450 RPM. We also know that "SpinLaunch’s first suborbital flight utilized about 20% of the accelerator’s full power capacity for the launch" which... I mean they been pretty loosey-goosey with terms so I'll bet they mean it was running at 20% of the critter's speed. SCUBALAUNCH PROBABLE ANGULAR VELOCITY = 108 RPM SCUBALAUNCH CORRECTED LINEAR VELOCITY = 168 m/s SCUBALAUNCH CORRECTED FLIGHT TIME = 17.1 s SCUBALAUNCH CORRECTED ALTITUDE = 1438m = 4717 ft which, again, is aspirational but looks a lot more like what they actually got on video. And i mean, I can't throw a scuba tank most of a mile into the air so kudos. But I don't really think Spinlaunch can, either. Can they spin a scuba tank in a 15m circle at 108 RPM? mmmmmyeah, I'll bet they can. Can they put that 30m circle under something kind-of vacuum-ish? mmmyeah, I'll bet they can. But you can hear the whirring. It's under vacuum-lite at best. But let's tie this poor sonofabitch back into our lawn dart. SCUBALAUNCH LINEAR KINETIC ENERGY = 200kJ SCUBALAUNCH MOMENT OF INERTIA = 3195 kg/m^2 SCUBALAUNCH ROTATIONAL KINETIC ENERGY = 772,000 kJ ...this is getting foreboding. That's 215 kW/h. We'll bleed off our pathetic 200kJ and be left with... about the same. We're going to swap our 3195 kg/m^2 moment of inertia for...much less.. NEW SCUBALAUNCH MOMENT OF INERTIA = 0.548 kg/m^2 SCUBALAUNCH SUICIDAL URGE = 8844 Hz Now. this is about where I argue, often ad nauseum, that the model is broken. 214kW/h is a lot of energy to put into a scuba tank. 15m is a hell of a lever arm. But there is no way in hell you're going to get a 9kHz flat spin out of a scuba tank. Ever. Under any natural, normal circumstances. But you're also not going to get zero. Conservation of angular momentum means the lion's share of energy you're pumping into the system stays with you. And it does so in an inconvenient form. Never mind any counterweight you may have, you're pouring the majority of your energy into you, not your launcher and you don't have a convenient way to deal with it. Worse than that you inherit it all at once when you fling your scuba tank into space. You can't get rid of it easily, either. I mean, you could keep your scuba tank from rotating with a linkage. You would then turn it into a cocktail shaker, unfortunately, and shaking your cocktail at 107 cycles per second (never mind 450) is going to be bad for your cargo ("jerk"). But Isaac won't be cheated - the conversion between one kind of motion and another conserves momentum and there is much in this system.
I ran the numbers for Spinlaunch's actual system. This is left as an exercise for the student. What you need to know is it's at a 45m arm, it weighs 11,200 kg, it's 25 feet long and prolly 3-4 feet in diameter. It's "suicidal urge" is gobsmacking. And again. Those aren't real numbers. But there AREN'T ANY REAL NUMBERS AROUND SPINLAUNCH. In order to get to that math you're spinning a pair of orcas around a 45m circle at 450 rpm and then flinging them into the air at Mach 6. I mean, c'mon. Presume you build this thing out of rainbows and hope, dumb-ass dynamics is still slapping you down. A half-gram USB-C connector under 10,000g weighs this: Design for that. Go ahead. Design for it in not one axis, not two axes, but the transition between those two axes. Also tell me you're going to aerodynamically stabilize a two-body problem with this thing. I don't know what kinda yaw is recoverable at transsonic speeds but I'll bet those are heroic calculations, too. And it kinda feels like this is more math than has ever been done around Spinlaunch.
so holy shit y'all - the accepted rotational velocity of a frisbee is like 2300 RPM - the accepted rotational velocity of a discus is like 400 RPM - the accepted rotational velocity of a clay pigeon is 2-3000 RPM So while I'm keenly uncomfortable with the idea of a lawn dart spinning through the sky at 146 Hz is 8700 RPM, I'm 100% A-OK with a frisbee doing 2300. So... maybe the difference between the lawn dart's suicidal urge and the lawn dart's reasonable behavior is the aerodynamics of the lawn dart. This does not portend well for the rest of the math.
I remember when they were trying to put enormous flywheels in the floor of public buses, which would be the source of motive power. Electromagnets under the ground at each stop were to recharge the spin of the flywheel. (Short version.) There was much concern expressed about the safety of an enormous piece of steel under the floorboards spinning at thousands of RPMs, and what could happen to the passengers in the event of a hardware failure or accident. I seem to remember the were going to address the problem with some sort of graphite flywheel that would basically explode into a giant ball of harmless thread in the event the flywheel failed for any reason. Spinning wheel, WHOOMPF, flywheel chamber full of graphite thread. Now... hear me out here... if the throwing arm in the SpinLaunch design is DESIGNED to explode into a cloud of graphite threads immediately upon release of the projectile.... does that burn off the energy left in the system after the projectile exits the building? Could that be a design feature to address some of the issues left behind once the launch happens? Ok, yeah, it's a stupid thought experiment. But then so is SpinLaunch and it EXISTS. I'd like to at least think someone in one of those rooms has wondered what happens to the arm once it releases...? Someone? Anyone...? Hello? Is this thing on...?
Lol yeah the gyrobus and its lesser-known younger brother, the General Electric Battle Top. Here's the problem: GE's clever idea was to dissipate 1.5 tons spinning at 10,000 RPM through explosive disintegration. That's 373 kJ of bad news. A couple pounds of TNT is 4200 kJ worth of bad news so converting your spinning war top of doom into explosive force, without conversion, is a quarter stick of dynamite. More or less. Work with me here. Spinlaunch, on the other hand, is at about 800,000 kJ assuming the arm that's flinging it has no mass. Assume we're just talking about the counterbalance - we get to dissipate the energy of one of these in our hypercentrifuge every time we fire it up. Again, assuming unicorns and rainbows, massless masses, perfect conversion, la la la la la. They'll want to move the office methinks.
Funny, I didn't even know about the GyroBus! The one I was thinking of was in the 2000's, and I can't find a link to it any more. I think the City of Seattle was looking into them, when I was with the Pioneer Square Community Association. Seems like we saw a presentation on this possible technology being used in Seattle transit buses. Google told me about this older Williams Racing project which used a flywheel as a power-assist in traditional ICE-powered vehicles, too:
On paper? It would. From conservation of (angular) momentum, it'd be a cloud of slower-moving (spinning) particles colliding with the walls of the chamber. From conservation of energy, it'd dissipate in a plethora of ways, but IMO mostly increase in temperature. Depending on the amount of energy to dissipate, if it were made from carbon like in your example, you might end up with friction lightning creating stuff like buckyballs, but mostly chain (=C=C=C=) or cyclic (same, but connect beginning with end) allotropes. Now, if you're asking if this is at all practical or doable...Now... hear me out here... if the throwing arm in the SpinLaunch design is DESIGNED to explode into a cloud of graphite threads immediately upon release of the projectile.... does that burn off the energy left in the system after the projectile exits the building? Could that be a design feature to address some of the issues left behind once the launch happens?
We'll use Tosser to accelerate carbon and make our own nanotubes, dammit! I even know how to get all the carbon we'd need for free: adopt legions of christian children, convince them to act naughty, collect the coal from their stockings. Use said legions as minions. We may be past Bond, but I can still turn it into Johnny English.
Just got off the phone with marketing, here are our two strongest slogan options: JAMES Dissociate." or MOLECULAR Bond." I think maybe the second, the first one maybe makes it sound like our company is destructive or bad."The name's Dissociate...
"It's Bond...
Yup, basically the same company. Watching that gud ol' Texasboi talk a lil' shit brought a tear to my smiling eye. It's unironically called "Not a Flamethrower" and is a piss-poor flamethrower. Closer to a butane torch, really. It feels really bad to churn out all this satirical content, only to be vastly, repeatedly outdone by Master Musk. But I'm busy. Tomorrow I am releasing my self-driving car software update and Donald Trump's healthcare plan.
Man, it's really too late/early for this, but I suspect the problems begin around here: Angular momentum is a vector quantity, and it's almost too easy to lose track of components and frames of reference even without not only having a wrong formula for L, but a wrong formula for the magnitude of L. On a first glance, your model can be simplified to a rod spun a distance r around an axis, parallel axis theorem style, but I'm gonna take this one in pieces. Updates inbound.KE = 1/2 Iomega^2. SHIT. Frickin' moments of inertia? I = L/omega. L = M x V x R. Uhhhm, M is mass is 1kg. V is angular velocity. R is radius around the centroid - hey we got all this shit!
L = r x p (L, r, p vectors) ; p = m * v (p and v vectors) |L| = m * r * v * sin(angle between component vectors r and v)
HAHahahahhahThe company has also been testing how spacecraft components can [survive] the high-g environment of the accelerator. “Very few people have experience designing mechanical and electronics systems to go into a high-g centripetal environment. It’s just a unique environment,” he said. “It’s been pretty surprising to learn how benign of an environment it is, and how not challenging the design effort turns out to be.”
LOOOOOOOOOOOOOOL Thereby putting them within an order of magnitude of - wait for it - Embry Riddle In other news, HOWARD HUGHES CONDUCTS FIRST TEST OF H4 HERCULESBuilding the system in a remote location at the spaceport was difficult, he said. “Being an hour away from any kind of civilization and support certainly presented its own set of challenges,” he said, exacerbated by extreme weather conditions there. “We needed a location that was a combination of being affordable, gave us the freedom to move quickly, and had airspace that goes all the way to the edge of the atmosphere.”
The centrifuge ran at 20% of its maximum power, he said. He declined to give specific details about the projectile’s flight, but said it flew at supersonic speeds and reached altitudes of “tens of thousands of feet.”
(Let the dissing continue) What "extreme weather conditions", exactly? This is New Mexico. Aridity is almost always desirable, because water vapor is the absolute worst, both for pumping down to vacuum and contaminating any instrumentation. Did you see how when the nosecone punched through that membrane, it wasn't exactly on a perfect tangent? Definitely either some translational or rotational motion. The sensitivity of the payload's attitude to the exact mechanics of the release from the lever arm cannot be overstated, and the idea of an active, on-board attitude correction system capable of combating fluid turbulence at Mach 6 is just plain offensive. I'm still trying to figure out what problem SpinLaunch is the solution to. Are the carbon emissions generated in producing the electricity required to spin up the arm and payload substantially less than the first stage of a conventional rocket? That's the only thing I can come up with. And I think the answer is likely a "no". or another good one is 4srsly tho: I want this to work. I would gladly eat my words. It's not going to work.Hey I know you didn't ask, and chuckle, well, this is certainly just a random thought I just had, sort of out of left field, almost! I'm like that, so spontaneous. Neurotic, in a way. But it's good! It works for me, and it's great for, like, big ideas, you know? And I'm a big big ideas guy. UGH, what was I gonna even say in the first place?! OH YEAH!! Look: It's easy to design for 10,000 g's, people just don't know it yet. $cout's honor.
yadda yadda yadda and the data we took is fantastic! No, you can't see it.
ZOMFG is there video? I must see this video. On the plus side it would merely have to compensate for the Standing Wave Apocalypse so... I mean, from a systems standpoint it'd be entertaining at least. I'm picturing an arrayed assortment of tunable Helmholtz resonators running some truly wicked linear servos. thing would look like a tokomak that got away. I'ma show you a picture Long story short: Gerald Bull helped develop a "launch system" for the Air Force that was supposed to literally shoot things into space. Air Force decided not to take it across the finish line so Gerald Bull took his tech to Saddam Hussein 'cuz you know what? "Space" isn't nearly as interesting to shoot at as "Israel" so the Mossad capped his ass. Basic problem with HARP (no, not HAARP, different conspiracy theories) is you can't make a barrel long enough to hit space. Turns out Gerald Bull was mostly interested in guns, not getting to space, but most people since then have been primarily interested in getting to space. So, I dunno, mid '60s the sci fi guys started saying "well what if you spin roundyroundyroundyroundyround until you're going hella fast and then let the fuck go?" Used to be you could find all sorts of cool '60s illustrations of massive 300km tracks in the Atacama desert with slopes pointing up the Andes and shit. The idea, basically, was you build yourself an accelerator not too different from CERN or the SSC or whatever except instead of atoms whooshing around it would be space capsules. The diameter would be determined by the amount of linear acceleration you could handle, the amount of centrifugal acceleration you could handle and how much you wanted to spend. I maintain that Hyperloop is a trojan horse SpaceX project to replace the rockets with a centrifugal launch system. Best way to figure out what sorts of problems you get from going Mach 6 in a circle is to go Mach 1 in a circle, and the best way to figure out those problems is to go less than Mach 1 in a circle. That circle, though, doesn't fit under a tent.Did you see how when the nosecone punched through that membrane, it wasn't exactly on a perfect tangent?
the idea of an active, on-board attitude correction system capable of combating fluid turbulence at Mach 6 is just plain offensive.
I'm still trying to figure out what problem SpinLaunch is the solution to. Are the carbon emissions generated in producing the electricity required to spin up the arm and payload substantially less than the first stage of a conventional rocket?
Our regional burn event is located right at the border of Vermont, on part of Gerald Bull's old research/launch site. Still loads of random old structures around, and it's nice that sound complaints will have to come from our USA neighbours - so will take too long to reach us in practice. The "human hamster wheel" thing we build with my friend Vlad this summer, was attached to what I guess is a conical metal base of some old tower structure, on its side. Nice to see Bull mentioned on here, listened to a few documentaries about the dude, just out of curiosity and proximity. The funny thing is how everyone at the festival keeps thinking any structure around is some "rocket part". While the land owner keeps wanting to sell off anything made of metal for a few thousand bucks worth of scrap metal. 
Frank Langella, Alan Arkin and Kevin Spacey No, I haven't watched it either but now I feel like I should
This was the first time scrolling down and reading the comments below a news article actually payed off. I don't expect it to happen ever again. hahhahahahanz Zimmer-esque. WE DID IT!!
Is ripping through a membrane good for attitude control? Asking for a friend. I wonder if their was enough of a pressure difference that the sudden pressurization of the chamber housing the lever arm did some damage. I dunno, the membrane isn't being aggressively sucked into the chamber, so far as I can tell. So yeah they definitely haven't solved the system-of-interlocks problem they'll need for the exit tube, then. There's no way you can use a membrane for full speed/power. Even if you find some magical membrane able to withstand the required pressure difference but still break gracefully, if that lever arm sees 1 atmosphere doing Mach 6, you're donezo. Like the whole facility. Ruined. Good luck. This shit is hilarious. Absolutely hilarious. There's a longer video in the article's comments that includes the phrase "I was skeptical at first". LOL "Then I heard Hanz Zimmer set to a tumbling hunk of lead, and I knew the world was changed forever".
Yeah that was the one you linked to initially and it's comedy goddamn gold Look. That "factory" video you linked to? The Zimmery one? (more Clint Mansell, tbh) 32 seconds in. Whoosh whoosh whoosh whoosh whoosh. Either (A) they foleyed in some whoosh whoosh whoosh whoosh to sound more awesomer because their GoPro was actually in reasonably hard vaccuum where there isn't any sound (certainly no high frequency) or (B) fucker weren't in vacuum dawg. Goin' with B. THERE'S AN IKEA STOOL IN THEIR PROMO MATERIALI wonder if their was enough of a pressure difference that the sudden pressurization of the chamber housing the lever arm did some damage.
Could it be picking up audio through the structure? That'd still attenuate the highs, though. If the chamber isn't at any vacuum whatsoever, what is the function of the membrane? Only other thing I can think of is helping contain shrapnel if the thing disintegrates inside. And that's really weird, we actually didn't use Ikea products in any of the labs that I know of. I guess, uhh, that's just the future. Like SpinLaunch.
it's been a part of their marketing it's bloody well gonna be there in the puff piece, dude. Kinda like how they had to show the damn thing spinning through the air like a goddamn boomerang and then go "no no no that's it heating up from the atmosphere ignore how it cools right back down and heats back up and cools back down and heats back up." The fact that you can see the yaw of their shotput in the tiny field of view of the exit shows you just how much English they put on that ball.If the chamber isn't at any vacuum whatsoever, what is the function of the membrane?
Dude it is the Everlasting Gobstopper of engineering comedy. I was discussing it with my cousin pretty much all night last night and it became clear that Spinlaunch has made no provisions for the hypothetical counterbalance that uhhh they're totally going to want to let go of once their "11,200 kg" payload isn't being constrained in a 45 meter arc at 450 RPM. 11,200 kg experiencing 10,000g has the effective weight of an Aframax crude tanker. In order to, you know, not put a bearing load equivalent to an Aframax crude tanker on your driveshaft you would ideally let your counterbalance go the same time as your payload but unfortunately they appear to have planned a control room there. Which is probably okay because frankly? Flinging eleven metric tons into the ground at Mach 7 is not ballistically dissimilar to Tunguska. So I guess you could imagine a structure capable of carrying an unbalanced load equivalent to an oil tanker through 90 degrees at 450rpm but that's the sort of phrase you don't usually see this side of the event horizon. The best part is you've got a discus with an effective weight that makes the top ten on this list but you think it's a javelin, and once it "breaks the seal" your three-Goodyear-blimps-worth of hard vacuum is going to eagerly slurp down the incandescent star you are making right at its mouth so if nothing else, at least the electromechanical apocalypse you've instigated will happen in a 6000k environment.
I'm in biotech so I have a lot of experience with centrifuges of various types, though almost all small. If you unbalance a centrifuge that weighs, say, 50 kg, by a few grams and you run it at 2,000 g, you get some serious wobble. You let it run for more than a few seconds and the machines all set themselves down, because you'll fuck the bearing quickly. You get to 100,000 g and then you're talking about balancing to the hundredth of a gram. Obviously it's all relative, and here I'm sure they've designed to the known forces and expected changes in angular momentum, but I just don't see how you don't break the rotor arm here. Maybe a sliding counterweight on the opposite arm that can be brought to the center immediately upon release? You could change the moment of inertia pretty quickly that way.
My mother used to point out the patched hole in the ceiling at one of her labs where a grad student loaded up an ultracentrifuge without a counterweight. I guess it was easier to do in the '60s. LOL they have done no such fucking thing. What cross-section shall we pick for the arm? How 'bout 2m? 10,000g x 11,200 kg x 9.81 = 1.09e12 n /2 = 500GPa. Know of anything with a tensile strength of 500GPa? 4130 chrome moly is at 0.435 GPa so normie shit is straight out. Kevlar 49 yarn is at 0.235 GPa (with 3% elongation - that's 14cm on this rig). Carbon nanotubes? 270-950 GPa! Hey we have a solution! Except they don't exist for lengths longer than a stack of dimes and we haven't exactly broached the subject of our release mechanism yet. If a cursory examination of the Newtonian mechanics at hand invokes unobtanium, we can safely argue that absolutely no analysis such as this has been shown to investors or shareholders. Somebody on the company either has a rich daddy or serious kompramat over Airbus Ventures, Kleiner Perkins or both. "Effective weight equal to an ocean liner" plus "brought to the center immediately" is a delightfully humorous concept. Conservation of angular momentum dictates that to take the counterweight force to zero by pulling it towards the center, velocity must go to infinity which, I mean, given everything else going on, why not? So now your gear motor must do more than sling a pair of ocean liners around at 450 RPM, it must also be capable of accelerating to light speed instantaneously. Or I dunno I guess you could do that and then hit your magnetic brakes in a futile attempt to absorb that energy. So what took you an hour to pump in, you now need to pump half of it back out as close to instantaneously as possible. Which I'm not going to do the math on but I'll bet it's in the neighborhood of having your facility struck by lightning.You get to 100,000 g and then you're talking about balancing to the hundredth of a gram. Obviously it's all relative, and here I'm sure they've designed to the known forces and expected changes in angular momentum, but I just don't see how you don't break the rotor arm here.
Maybe a sliding counterweight on the opposite arm that can be brought to the center immediately upon release?
Uh, yeah. These days every UC is programmed to go to low speed to sense the balancing before it ramps up. From what I understand there were many lab incidents that led to those engineering changes. Even if no one gets hurt, you're still out $80k when you have to buy a new machine, because user error voids the warranty.My mother used to point out the patched hole in the ceiling at one of her labs where a grad student loaded up an ultracentrifuge without a counterweight. I guess it was easier to do in the '60s.
Yeah every piece of lab equipment I've ever seen has been safe as houses... with the exception of the janky shit bought out of China that will totally kill you given half a chance. My wife's college had some industrial herb grinders that would absolutely dispose of a body by accident.
You know, sometimes one comes face to face with one's shortcomings, and this might be that moment for me. When faced with a factset that doesn't add up, my reaction is almost always, "Well if I can see that this is bullshit in 2 minutes of calculations, then clearly I'm missing something." Techbros notwithstanding, my reaction is rarely. "Oh, easy, they're lying for money." I can be very credulous even at times when everything says to be the opposite.LOL they have done no such fucking thing.
If I hadn't had my very own "lolnope" moment with Theranos I might feel the same. But I mean https://en.wikipedia.org/wiki/ADE_651 That right there? is a dowsing rod bought by Seal Team 6.
Ah, a rookie mistake: you counterbalance your payload with a second payload, release 180 degrees later. And people thought a theorist can't engineer good. I'm mildly disappointed they aren't hiring anyone to develop inertia dampeners or cetacean tractor beams.Spinlaunch has made no provisions for the hypothetical counterbalance
I can't find it at the moment but I remember working out the math of the speeds he was promoting for passenger travel and concluding that you would need a greater than 2 mile turn radius or something to stay below 1 g. It was very evident from the beginning that Hyperloop was not a viable transportation idea. Didn't stop any amount of jizz being spilled over it though, because most people don't know thing one about physics.I maintain that Hyperloop is a trojan horse SpaceX project to replace the rockets with a centrifugal launch system.
I suppose that it'd be more viable on the Moon or Mars, where gravity is lower, the atmosphere negligible and chemical propellants are harder to get than, say, sunlight. In that regard, I'd also like it to work, but god damn if the reports aren't silly af.I'm still trying to figure out what problem SpinLaunch is the solution to. Are the carbon emissions generated in producing the electricity required to spin up the arm and payload substantially less than the first stage of a conventional rocket? That's the only thing I can come up with. And I think the answer is likely a "no".
SpinLaunch videos are better than anything they got streaming on Hulu or Netflix these days. No cap I'd kill to watch a video of Isaac Arthur commentating on the suborbital accelerator tests at Spaceport America and how a space elevator will be constructed at Spaceport America by 2050 which'll transport passengers to beyond the Karman Line where pioneers take off for 9 month trips to colonise the moons of Saturn or Jupiter. Isaac f%^ing Arthur
SpinLaunch videos are better than anything they got streaming on Hulu or Netflix these days. No cap I'd kill to watch a video of Isaac Arthur commentating on the suborbital accelerator tests at Spaceport America and how a space elevator will be constructed at Spaceport America by 2050 which'll transport passengers to beyond the Karman Line where pioneers take off for 9 month trips to colonise the moons of Saturn or Jupiter. Isaac f%^ing Arthur need more people like him
For $110 million (just took the first value, don't exactly care myself)? It's about 0.1% of what ISS cost or around 1% of SkyLab (adjusted for inflation) with MIR fraction somewhere in-between those two, so not much. Don't get me wrong, I'm currently torn between continuing to laugh at it or rallying folks here to salvage it as an exercise, so my opinion is a few notches above "burning money," but let's not overstate the cost. Now, if you asked how many people could it free from medical or inherited debt, that'd no doubt be more impactful. EDIT: I originally made an error by an order of magnitude, holy shit I'm tired.