Askad Colisels render

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Askad Colisels render

Post by Graham Kennedy »

A heavy cruiser of the Turgran Navy, used during the liberation of Humanity from their subjugation by a species called the Saravan. A four spike repellor and four sails. The Colisels was the first major ship class with armoured sails.

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Re: Askad Colisels render

Post by Mikey »

I like the integrated missile/directed-energy turrets, and the "captain's yacht."
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Re: Askad Colisels render

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Mikey wrote:I like the integrated missile/directed-energy turrets, and the "captain's yacht."
The former were inspired by the Russian Kashtan CIWS system :

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The transports on the outside of the hull is common in this era and earlier. Easier than having internal hangars, though much less convenient.
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Re: Askad Colisels render

Post by Graham Kennedy »

Greatly improved versions of the missile launcher... compare this :

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With this :

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And the pièce de résistance... this is by FAR the hardest thing I've ever done in blender :

http://www.ditl.org/Vanfolder/0001-1360.avi

This animation is huge - 200 MB - so be patient!
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Re: Askad Colisels render

Post by Graham Kennedy »

So I have been designing ships that generate gravity via rotating hulls lately, and I got to thinking about having crew working on systems mounted on the hull. First I rendered a couple of pictures with guys standing on the hull, but then I realised that this is really silly - in a rotational hull, "up" is towards the rotation axis and "down" is away from it. So if you simply stood on the hull, you'd instantly fall down - flying off into space.

The first solution seemed to be magnetic boots, but with a little thinking that wouldn't work. If you stopped the rotation and went zero gravity, then clomping around the hull on magnetic boots would be fine, sure. But if the hull is rotating, then the gravity just outside the hull is about the same as the gravity just inside the hull. So picture being laced into a pair of nice tight boots, and then having those boots stuck to your ceiling. Now imaging hanging there, upside down... whilst trying to unbolt a panel, unplug a circuit board, plug in a replacement... etc. It's certainly possible for a human to work upside down, but can you imagine anything more exhausting? Nobody could be expected to work that way for more than a few minutes at a time.

So here's my solution... the Hull Crawler. A Crawler is essentially a box with four very powerful electromagnetic clamps at the top. Underneath is a high capacity battery and four winches; wires hang down, holding a simple seat arrangement. The astronaut sits in the seat; he has a control so he can lower and raise himself, and by modulating the fields in the magnetic clamps he can have the Crawler move in any direction.

If you want a mental image of how it would work, imagine yourself hanging off the bottom of, say, an aeroplane in flight. Ignore the wind - there's none in space. Your crawler would clamp to the bottom of the plane, and you'd hang under it on a seat connected by wires. You could have the crawler move around the bottom of the plane, winching yourself up so you could inspect the hull or lowering yourself to a convenient height.

I love this little gadget - it's a brilliant example of how modelling a ship in 3D and animating it rather than drawing it in photoshop has given me a new perspective on what it would take to work on a ship like this. Such small but practical details help these fascinating fantasies come to life and feel a little more real in my head. And in all the sci-fi I've read and watched, I don't know that I've ever seen or heard of a gadget like this, even though it's a simple, obvious, and elegant solution.

I should say, the Astronaut figure is not mine. It was created by "xMoneyShadow" and posted on the Keen Software House forum.



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Two astronauts on Hull Crawlers. The large round object behind the guy on the left is a gamma ray laser cannon, and the thing to the right and behind that is a sensor array. Notice that the guys in the crawlers stick out at different angles - one of the things about rotational hull gravity is that "down" is along a radius to the axis of rotation. As a matter of fact on Earth it's similar, with down being along an axis pointing towards the center of gravity of the Earth - only the Earth is so huge that people in the same room, even the same city, are essentially standing parallel to one another (you have to be around 70 miles away from somebody before you are even one degree different.)

But on a rotational hull that's around 150 feet across, somebody who is even as little as 30 feet further around the hull is at an angle about 23 degrees different to you - you'd see them hanging out on a 23 degree tilt, whilst they would see you the same way. The same would happen inside the hull - a guy thirty feet away from you down a corridor would slant 23 degrees towards you. It would be disconcerting to new recruits, and something they would have to get used to with experience.



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A close up of a hull crawler. Redundancy at work here - four magnets on top, though any one could hold a fully equipped astronaut twice over. And four wires to hold his seat, though any one is strong enough to hold him many times over. There should be a safety line attacked too, but I haven't designed it yet!

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Re: Askad Colisels render

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So thinking about it, a crawler really should have a safety line - it's all very well having four strong cables holding the seat, but if the astronaut should lean forward and slip off that seat then it's a long, long, LONG way down!

So I added a quick and dirty safety line between the Crawler and the astronaut. Now if you slip off the seat you fall twenty or thirty feet down and dangle at the end of the line until you can haul yourself up - though given how heavy a guy in a suit is, probably you wait until somebody can come over on another Crawler, lower themselves to your level, and hoist you back up to your seat.

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Re: Askad Colisels render

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Finished version of the Hull Crawler, now with a seat back, a lap safety belt, and a control panel. I figure there would be a wireless control option so you could use the suit controls to control it, bu there would be an on-mount control panel as a backup. I've also put an airlock door into the hull, big enough for a Crawler to fit through. There would need to be some contraption to lower people out... I'm thinking there would be a rail above the airlock door with a metal plate. You stick the crawler to the plate using the magnets, sit on the seat, and then the doors open beneath you and the plate lowers down until it's flush with the hull. That way you can just drive off it onto the hull.

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Re: Askad Colisels render

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So one of my favourite books is by Niven and Porunelle, and it's called "The Mote in God's Eye". It prominently features the INSS MacArthur, a ship that uses rotation for gravity. One of the things that always stuck in my head about the ship was that the captain had a cabin that hung out from the hull in a kind of tower. It wasn't used in combat situations ("For spin gravity it was conveniently far from the ship's axis, but in a battle it would be the first thing shot off."), but for peacetime it had a nice panoramic view of the ship "above" and space around.

Inspired by that, I thought I'd stick such a tower on the Colisels. I don't know that I'd keep it as a permanent feature, just fancied having a look-see. This was actually very easy to knock up - make a cylinder with only 16 faces, scale the top end up a bit, set it to a glass material. Then copy that cylinder, leaving it on top of the first; use a feature called "wireframe" that removes the faces, leaving only the framework - and a setting on that feature can thicken the frames to make them into frames for the glass. Solidify the top and bottom, stick a cylinder in for the lift and some rods to hold it to the hull, put a light source in the room and that's it, job done. The people inside and furniture are all imported from the Theramel recreation deck with I did a while back.

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And a guy in a Hull Crawler comes to say "Hi!" to the guys in the tower! :wave:

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Re: Askad Colisels render

Post by Graham Kennedy »

Colisels rotating. Note the tower, and you can just see a few crawlers on the hull.

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Re: Askad Colisels render

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Launching one of the ship's boats, and more experiments in camera movement. This is a complex sequence; the camera is panning past the ship to begin with, then as it passes it rotates to track the pressure hull. As the boat launches the camera tracks up and right to follow it, then back down to the ship again, all the while continuing the original track and rotate.

Notice a couple of glitches in the last animation of the rotation, most notably that whilst the tower rotates with the ship, the furniture and people inside the tower just hang there in space beneath the ship! Also a couple of the safety lines on the crawler people just hang in space, too. All that's fixed in this new iteration.



Launching the boats is fun, too. No need for catapults or anything, since they are on the hull you just release them and they are thrown away from the ship. Probably the best known example of this type of launch is the Babylon 5 fighter launch sequence:



But what always bothered me about that is that the ships drop radially away from the station, straight outwards - but circular motion doesn't work that way! If an object is moving in a circle, at any given point the motion is at right angles to the radius of the circle, not along it. What the fighter "wants" to do according to Newton's first law is continue moving in that right angle direction, not to drop straight away. It's the fact that the fighter and the pilot inside it is attached to the station and thus constantly being pulled off that tangential line into a circular path by a force which provides the "artificial gravity" effect in the first place. Same thing happens if you tie a stone to a string and whirl it around your head in a circle - at any given instant the stone is trying to move in a straight line at 90 degrees to the circle, but the string is constantly pulling it off that straight line with a force towards the centre.

Thing is, I could never quite visualise what that would look like from the point of view of a person on the rotating object. I had a suspicion that the launching fighter/boat might appear to simply drop away radially after all... that didn't seem right, but I couldn't quite work out what it should look like. Well the second animation here has the camera perfectly tracking the rotation of the ship, and we see the result is that the boat moves out away from the ship in a nice curve. Thinking about it that makes perfect sense, because trigonometry is at work here so intuitavely, the motion would have to follow a sine or cosine (or maybe tangent?) function. Easy to say it makes sense after you've had a computer model it and show you the right answer, of course!



I should say, the boats are supposed to be lowered away from the ship about ten feet by a telescoping attachment before launch - otherwise the wingtips come mighy close to clipping the hull as they fall away. Unfortunately my blender skills aren't up to being able to animate that, as yet.

Incidentally I've been working on the size of the Colisels. The original intent was to make it a pretty cramped environment - the feel of a typical World War II heavy cruiser or thereabouts. Although the ship is pretty large - from the repellor engine "pincers" to the front of the sail pod is 1,109 feet - most of that space is fuel tank. The six big white cylindrical things behind the rotating hull are all fuel tanks, making about 65% of the ship's total volume. The spherical object behind them is the ship's reactor system, which is a "pinch singularity" reactor - essentially a kind of miniature black hole, which tears matter apart as it falls in and radiates energy much as any black hole does. A step up from fusion, it converts matter to energy with around 15% efficiency (it's difficult to find hard numbers, but 30% is a figure I found for how much matter turns into energy as stuff falls into a black hole. I figure half that for a working reactor.)

Anyway, the real ship is the pressure hull, the rotating section. This comprises a cylinder 216 feet across and 196 feet from front to back. Under acceleration it's essentially a round building with 15 circular floors, each 216 feet in diameter and 13 feet tall. Hence the total deck area is 549,652 square feet. You'd lose some of that because the central core is essentially three big empty spaces one atop the other, each five decks tall. Each is criss-crossed with walkways, ladders and elevator shafts, etc. Those spaces are full of things like great big oxygen tanks, water tanks, etc - plus giant flywheels to balance out the rotation, since this ship only has a single rotating hull rather than a contra-rotating pair. So take the central core as three five story atriums running up the entire length of your building. That knocks some area off your total, giving the ship an area of 481,558 square feet.

Under rotation things are a bit more complicated - take your cylindrical building and knock it over onto its side. Your building then becomes a series of nested cylinders. The inner one is 85 feet in diameter and 196 feet wide (still subdivided into three, of course); the total area of this space then is 52,751 square feet. Wrapped around it are a further five cylindrical decks, each 26 feet larger in diameter but the same width. Those five total 507,224 square feet, for a total area of 559,976 square feet. So about the same area either way, give or take a little.

In terms of gravity, the Turgrans prefer a higher gravity than Humans do; this ship takes 228 frames to spin 360 degrees, or a lap every 9.5 seconds. Since the hull is 216 feet across that means the outer hull (deck 6) is spinning at just under 50 mph. So the gravity on that hull is 1.47 gees. Next deck up it's 1.29, deck 4 is 1.12, deck 3 is 0.94, deck 2 is 0.76, and the inner deck 1 core is 0.58. Thus any Human crew would usually prefer to stick to deck 3, and their accommodations would be there, whilst the Turgran's quarters would be on the outer deck. The tower would be getting on for about 1.8 gees, difficult for humans. Naturally, the ship can adjust the gravity any way the captain likes by changing the rotation speed.

So how does the area compare to present day ships? It's maddeningly difficult to find the deck area of any given ship, but take the Iowa class; they're 861 feet long by 108 feet wide. That's 92,988 square feet... but of course, a lot of area is lost because the ships aren't a box. The stern is rounded and the bow is long and relatively thin. Let's guess that the actual deck is about 65% of that area, then, or 60,442 square feet. The Iowas have up to six decks in the hull itself, but they lose a lot of area to big open spaces for the engines - much as the Colisels loses deck space to those three big atrium areas. And of course the Iowas gain deck space from the superstructure areas, which are about three decks tall for the most part, though they're relatively small compared to the ship as a whole. So let's guess the total area is about seven times the size of the deck we calculated, or about 423,100 square feet.

So we can see that the habitable area of the Colisels is going to be about a third larger than an Iowa class battleship. That's rather larger than I expected it to turn out when I designed the ship!

I also got to thinking about life support and specifically, oxygen supply. Originally I envisaged carrying big tanks of Oxygen around in the ship. However, that's actually not that practical. Let us delve into the mathematics of breathing! (Yes, for fun! Isn't this how you have fun?)

An average person takes 12-20 breaths per minute, with each breath averaging half a litre. The air going in is 20% oxygen, and the air coming out is about 15% Oxygen (the loss of oxygen is made up for by the extra carbon dioxide we breathe out, of course).

Therefore in one minute we breathe 6-10 litres of air, and use 5% of that, or 0.3-0.5 litres of oxygen. For a full day, the figures are 432-720 litres. Let's go with the high figure from now on.

So if we were going to carry oxygen tanks at room pressure, we would need to release 720 litres per person per day into the air to make up for what's being breathed. That's a cylindrical tank roughly 1 metre long and 1 metre in diameter. The 451 person crew of the Colisels would get through 451 such tanks in a day; 13,530 tanks in a month, or 81,180 in a six month cruise. That's a lot of tanks!

But of course it would be madness to have O2 tanks under one atmosphere; SCUBA tanks are routinely charged to 3,000 PSI, or about 200 times atmospheric pressure. So each person only needs one 3.6 litre tank per day, we only need 406 tanks under that pressure for our six month cruise.

Of course... pressurised Oxygen tanks are not inherently safe things. They can explode, especially when they're in a ship that's going to get shot at. So best to have only a few of these, say fifty, and call them a life support backup system.

So where do we get our air from? Water.

Water is H2O, of course - two atoms of hydrogen, one of oxygen. The hydrogen atoms only weigh 1 atomic mass unit each, the oxygen weighs 16. So by weight, water is 16/18ths oxygen - 88.89%! And water is, of course, not very explody by nature.

Of course you can't breathe water. But run an electrical current through water and it splits up via electrolysis into hydrogen and oxygen. To break down one mol of water takes an absolute minimum of 237 kJ of electrical energy. A mol of water masses 18 grams and will yield 22.4 litres of gas when broken down, of which 16/18ths is oxygen - 19.91 litres.

Thus, to provide the 720 litres of oxygen a person needs in one day, one must break down 720/19.91, or 36.16 mols. Remember breaking down a mol takes 237kJ, so the total energy required for this is 8.57 MJ. And thus supplying the oxygen needs of the entire 451 crew takes 3,865 MJ per day.

That sounds a lot, but per second it works out to 44.73 kW. The equivalent to about a dozen electric ovens. Throw in efficiency losses, then have a reserve because people who do demanding physical work use a LOT more oxygen, and the ship may have to take on refugees, host marines, etc... let's call it 150 kW.

How much water, though? Remember we;re breaking down 36.16 mols per person per day, and a mol weighs 18 grams. So we need to go through 650 grams of water per person per day. A liter of water weighs a kilo, so 0.65 kilos is 0.65 litres. For a six month trip for 451 people, that's 52,767 litres of water you'd take along to turn into oxygen. About 52 tons - more like 150 tons, to give a nice fat reserve given that people will exercise and whatnot, using more air.

So not only is a water tank much less likely to explode than a pressurised oxygen tank, but 0.65 litres of water per person per day compares extremely favourably with a 3.6 litre oxygen tank per person per day - on a ship where space is at a premium, reducing the size of your oxygen supply fivefold ain't nothing! (As an aside, guess how modern submarines provide oxygen for the sailors... yep, by this exact method.)

So oxygen provision would comprise say fifteen electrolysis machines scattered around the ship, each with a one ton tank of water attached. That sounds a lot, but it's only a cube a metre on a side.

Given the size of the ships being larger than I'd envisaged, I'm thinking about boosting the crew size to restore the crowded and cramped image I had in mind. The Iowas had as many as 2,700 men on them in WWII, and 1,800 even in the 1980s iteration. The Colisels would need a good 2,400 - 3,500 to match that population density. Seems excessive... I'm not sure what they would all do with their time, lol.

Anyway, there we go. A look into the inner workings of a ship of the future!
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Re: Askad Colisels render

Post by Graham Kennedy »

And now a point of view from a guy standing on the hull watching the launch. This time I tried adding stars... they worked out okay, but lots of room for improvement there.

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Re: Askad Colisels render

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I'm putting little (or not so little, lol) "lectures" on the physics of ships here just because I want to have a place to put down stuff I'm researching about them. I find it interesting, maybe others do too! And if not... think but this, and all is mended - that you have but slumbered here, while these visions did appear. :)

So, how much energy in a rotating hull? In early designs in the Coalition universe (long predating the Coalition itself of course), ships had two pressure hulls rotating in opposite directions. The idea of that is to cancel out gyroscope issues and such, but also - you push a hull to rotate in one direction, the ship will tend to want to rotate in the opposite direction. It's the same problem helicopters have, and why they have tail rotors to country that tendency for the body to rotate opposite to the main rotor.

Well by the time of the Colisels the idea is that they have a more sophisticated system whereby massive flywheels at the ship's axis rotate opposite to the pressure hull to balance it. They are much smaller and much less massive than the hull, of course, but they spin much faster. There's also the advantage that they are how you get the hull spinning in the first place - rather than use rockets or whatever to get the hull spinning, you spin the flywheel up and the ship will automatically be rotated in the opposite direction. To reverse it you put the brakes on the flywheel and it slows the hull rotation down.

Now I always had that idea, but I've never checked into the math to see just what that would take. So here goes.

According to this, the kinetic energy of a flywheel which comprises a single solid rotating cylinder is given by the formula :

KE = 1/2 I w^2

Where I is the moment of inertia and w is the angular velocity in radians per second. (A radian is 360/2pi, or 57.295 degrees).

Moment of inertia for a solid disc is given by :

I = 1/2 m r^2

Where m is the mass of the disc and r is the radius.

So we substitute equation two into equation one like so :

KE = 1/2 x 1/2 x m x r^2 x w^2

KE = 1/4 m r^2 w^2

So... I'm going to assume the Colisels pressure hull is a solid cylinder, 33m in radius, 60m wide, and with an average density of 340 kilos/m^2. (In physics we are allowed to make such preposterous assumptions!) It rotates in 9.5 seconds, so w = 2Pi/9.5 = 0.6614 rad/s

Anyway, that yields a mass for the pressure hull of 70,000 metric tons. So we can calculate the kinetic energy as :

1/4 x 7x10^7 x 33^2 x 0.6614^2 = 8.34 x10^9 J.

So there we have it... getting the pressure hull of a Colisels up to speed requires putting 8.34 GJ of KE into it. That's not too bad, a good sized power station in the present day could do that in a few seconds!

Okay. Now for the system to work there needs to be a small flywheel in the center of the ship which has the same kinetic energy. So we use the same equation and work backwards, using different numbers for size, spin rate, etc.

So how big a flywheel? Let's make it a solid disc of steel, 5 metres in diameter and 6 metres thick. That's 117.81 m^3 of steel, so at a density of about 8000 kg/m^3 our flywheel masses 942 metric tons. So...

8.34x10^9 = 1/4 x 942477 x 2.5^2 x w^2

w^2 = 5663.37

So w = 75.25 rad/s

That's just shy of 12 revolutions per second. 720 RPM.

That doesn't sound terribly excessive, now does it? When I set out on this I was picturing a massive flywheel that would spin at hundreds of thousands of RPM. In fact with that modest rotation rate (much slower than a washing machine on spin dry) I am thinking to redesign the flywheel to be significantly less massive and faster - why cart a thousand tons of extra mass around if you can make it that much smaller and faster?

Now of course a solid disc doesn't make a great flywheel. You're better off with a metal hoop, with all the mass at the edge, because then the velocity of all your mass is as high as possible and thus you're getting better energy storage for a given mass. But of course a mathematically perfect hoop is a practical impossibility, partly because a real hoop has to have thickness so some mass is always going to be closer to the axis than the rest, and partly because if all the mass is on the rim then there's no structure to hold it in place. Better to imagine something like a bicycle wheel - just enough structure in the spokes to hold it together, and then most of the mass in the rim.

That's hard to model, but you can ignore the spokes and do the calculation for a thick walled cylinder. The equation for this is :

I = 1/2 m (ri^2 + ro^2)

Where ri is the inner radius and r0 the outer radius. Plugging this into the original KE equation gives us :

KE = 1/2 I w^2 = 1/2 x 1/2 x m x (ri^2 + ro^2) x w^2

KE = 1/4 m (ri^2 + ro^2) w^2

Let's keep our cylinder 5 m in diameter and 6 m high, but make the walls half a metre thick - so outer radius 2.5m, inner radius 2m. That makes it weigh 339,291 kg :

KE = 1/4 m (ri^2 + ro^2) w^2

8.34 x10^9 = .25 x 339291 x (2.5^2 + 2^2) x w^2

w^2 = 10742.63

w = 103.65 rad/s

So 16.5 revolutions per second; 990 rpm.

Still good - in the washing machine spin dry range.

Yet more realistically, and for redundancy, I would split this up into multiple flywheels - that's why I made it a whopping 6 metres thick. Since everything scales in linear proportion to length of the wheel, we can just chop it up lengthways really easily!

I said earlier the Colisels had a central core split into three large atrium-like spaces. So picture our flywheel chopped into six 1 m thick wheels, and two mounted in each compartment. They'd all be mounted on the rotation axis of the ship... of course the wheel itself would be concealed within a protective shell - flywheels are dangerous, and you really don't want a 340 ton mass spinning at nearly a thousand rpm that some fool can accidentally stick his head into. Not to mention that if something crashes into it and it becomes unbalanced it will pretty much be like a bomb going off. Literally a bomb, our flywheel has a kinetic energy equal to the energy released by about a third of a ton of TNT going off. Not a nuke by any means, but more than enough to redecorate a significant portion of your ship.

Which is another reason to have multiple wheels - six times less damage if one does rip free.

Connected to the flywheels would be some sort of motor, and then bracing to hold them in place. The bracing would need to be massive and solid - remember you're using these things to push start or break a 70,000 ton mass! They would be very prominent units indeed.

So with that in mind, next I will hit blender and render what I think they should look like. Watch this space...
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Re: Askad Colisels render

Post by Graham Kennedy »

The flywheel housing and bracing struts :

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Note the gratings the guys are standing on; in these images, the ship would be under acceleration with the bow of the ship in the direction of the guy's head and the stern in the direction of their feet. But I got to thinking how you'd reach the thing under rotation. So the gratings have a rather nifty design; under rotation the metal rods supporting the handrail become rungs of a ladder, with the metal hoops being guardrail things you get on ladders on buildings sometimes. The grating becomes a vertical wall under rotation, so there is a platform that folds out to provide a platform to stand on, like so :

Image

Don't know what those stripes on the support pylons are - I thought they were shadows, but they're not. Never seen that effect before. :wtf:
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Re: Askad Colisels render

Post by Graham Kennedy »

Harumph. I made a five deck tall central atrium, and it turns out that two of these won't fit inside it. :bangwall:

Soooo, options.... 1) Make half as many, each twice as massive. Could do that easily by making each flywheel disc twice as tall. Or 2) Double the energy of each by making them spin faster. No redesign required, and since the RPM rate has turned out to be fairly modest so far this seems like the way to go.

I could do a simple two for one substitution, put one in each atrium for three. But something strikes me as wrong about that, it just seems kind of untidy to have an odd number, somehow. Sooooo... could have one in the forward atrium and one in the aft, with other stuff in the middle one? Of make the atriums themselves taller and only have two of them, with a unit in each? Or make two tall atriums and put two units in each?

Well the pressure hull is fifteen decks tall under acceleration, so two atriums doesn't fit the deck plan well. So three atriums, one unit forward, one aft, it is. Put something else in the middle atrium.

So we're going from six to two. This is gonna be a good leap in spin speed!

I set up an excel spreadsheet to do the math, save all that tedious button pushing. So our ring is 2.5 m outer radius, 2 m inner, 1 m wide. It's made of steel, density 8000 kgm^-3. That gives it a mass of 56,548 kg.

To store 8.34x10^9 Joules on two units, each must hold 4.17x10^9. Plugging the numbers in, our wheel needs to spin at 1,620 RPM. Hellish fast - the outer rim would be rotating faster than the speed of sound. (It would spin in a vacumn, of course.)

Flywheels of this size/mass have been built, and faster flywheels have been built... not sure if one this size AND speed has been built though. Wonder if steel could stand up to the forces involved? If not, it needs to be futuristic material of the future! (Or a bigger, slower flywheel...)

I also started filling in other things that would be in the atrium. I stuck water tanks around the flywheel on the theory that if one of these things ever rips loose, the best thing it could slam into would be a nice big steel tank of water - lots of impact absorbtion potential there.

More to come...
Give a man a fire, and you keep him warm for a day. SET a man on fire, and you will keep him warm for the rest of his life...
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