Topic: WCDT 2111-2115 (Jan 30 - Feb 3, 2012) - QC in SPAAAAAAACE!!! Week 2! (Read 72698 times)

Arancaytar · « **Reply #50 on:** 31 Jan 2012, 03:05 »

Quote from: Skewbrow on 31 Jan 2012, 02:21

Quote from: Arancaytar on 31 Jan 2012, 01:11
Quote
the spinning section

It makes sense to keep the hub still, of course, because you don't want to make spaceships have to start spinning before docking. But now I'm wonder how they transfer from the hub to the spinning section without some awful acceleration or alignment problems. At best, I can imagine a lift-tube that rotates along with the rest, and that periodically aligns with a hatch in the hub. You'd have to time your entrance well to avoid getting squashed, though.

The same question was bothering me in Ender's Game, too.

As was explained by Akima and PWHodges in the "spinning space station" thread a practical solution is to make the docking spaceship spin at the same rate as the station. That is probably preferrable to docking with a non-spinning hub connected to the rest of the space station by a giant ball bearing or something. The latter solution would just move the problem from the hatch separating the spaceship from the hub to the connection between the spinning and non-spinning sections of the station.

Because the spaceship is so small (in comparison to the space station), the resulting centrifugal acceleration (proportional to the radius of the ship, or more precisely, to the distance from the axis of the rotation) is barely noticeable. More like a drift towards the "floor". I am assuming that the spaceship docks at its nose (or the rear-end), but I may be wrong about this.

Now that I think about it, maybe Hanners' "spinning section" remark didn't actually imply that only the rim moves, but that only the rim moves fast enough to experience centrifugal force.

Soulsynger · « **Reply #51 on:** 31 Jan 2012, 03:15 »

In Comic 2111 I don't see any room for a central docking bay on the top or bottom of the station... but I DO see some airlock-like looking extension on the lower section...
(edit: and in 2112, they're coming out of a sort of gangway...)

This has me a bit puzzled. Wouldn't it be VERY hard (if not impossible) to dock at that point if every part of the station rotates at all times? I mean... trying to match the station's rotations per minute with an external object circling it would create SOME sort of centrifugal force, wouldn't it?

... or could the station cease its rotation for a couple minutes whenever docking occurs? (That would never be cost- or fuel-efficient of course, but would it be possible?)

WAYF · « **Reply #52 on:** 31 Jan 2012, 04:42 »

I only just noticed,

1) The funniest part of this comic is actually Hannership saying "You may now exit the, uh, me", which rather reminds me of

Quote from: Homestar Runner

Everybody loves the me! I'm a terrific athlete!

2) Marigold has some sort of square yet skin-shaped patch on her neck. Is that how her medicine was administered, and is all medicine administered like that in the QC universe?

Milesb · « **Reply #53 on:** 31 Jan 2012, 04:42 »

Isn't it possible that the small section which sticks out to the right on the lower part of the station (just above the antenna array) could be a section/module spinning anticlockwise at the same speed as the station spins clockwise (or vice versa), making it relatively stable enough to be docked with?

Also: loving the floaty shoelaces.

Redball · « **Reply #54 on:** 31 Jan 2012, 05:07 »

I had a violent bout of vertigo 30 years ago. Got immediate relief from a patch applied to my throat. It administered scopalamine, as I recall.

mike837go · « **Reply #55 on:** 31 Jan 2012, 05:23 »

Panel 3 there's a side of Marigold we've never seen before!

Tanman · « **Reply #56 on:** 31 Jan 2012, 05:57 »

Oh Marten, your hipster chic will be your undoing! That single strap tote will be next to useless in weightlessness!

Nerds with two strap backpacks rule in space!

zmeiat_joro · « **Reply #57 on:** 31 Jan 2012, 06:00 »

Quote from: WAYF on 31 Jan 2012, 04:42

2) Marigold has some sort of square yet skin-shaped patch on her neck. Is that how her medicine was administered, and is all medicine administered like that in the QC universe?

Probably administered somewhere on the carotid arteries. Makes sense for a drug targeting the vestibular system, but what about the blood-brain barrier? Is the vestibular system outside it? Can you help by targeting it directy? This is not my forte...

EDIT: Didn't notice Redball's post.

pwhodges · « **Reply #58 on:** 31 Jan 2012, 06:10 »

Quote from: Tanman on 31 Jan 2012, 05:57

Oh Marten, your hipster chic will be your undoing! That single strap tote will be next to useless in weightlessness!

Hanners is happy to use one, though.

And Marten's is on the wrong shoulder in the first frame.

DSL · « **Reply #59 on:** 31 Jan 2012, 06:15 »

Given what's depicted so far, I'd vote for a hub that can be de-spun (contra-rotated) at least temporarily to meet a docking ship. This allows for docking ports off-axis, which you'd need to allow for more than one ship at a time to dock. The big (solar?) panels shown would have to work the same way, to maintain orientation to the sun.

For a depiction of moving from the non-spinning section to the spinning section, see also ... Kubrick's 2001, which shows Bowman and Poole leaving Discovery's "Carousel" for the passageway to the bridge and/or pod bay. (Ignore that scene with the stewardess aboard the Aries. She didn't need to do that whole walking-around-the-circle thing; no passengers were watching. She was just messin' around.*)

Marten's first attempt to enjoy free-fall is, unfortunately, teaching him the same lesson his earthbound life has taught him: Launch too enthusiastically, try to enjoy life, and you get hurt. Can't catch a break, unless it's his nose and the bulkhead. Berf.

Also, Marigold's changed into long pants. She must have had a bad time on orbit, poor thing.

*Yes, I know it was a camera trick on a rotating set in that one-g environment we like to call Earth.

zmeiat_joro · « **Reply #60 on:** 31 Jan 2012, 06:32 »

Is some form of regenerative braking possible in a structure rotating in a vacuum? It seems to me there should be. The more I think about it.

Jabberwocky · « **Reply #61 on:** 31 Jan 2012, 06:37 »

Quote from: Binary on 31 Jan 2012, 02:56

Quote from: Skewbrow on 31 Jan 2012, 02:21
As was explained by Akima and PWHodges in the "spinning space station" thread a practical solution is to make the docking spaceship spin at the same rate as the station.

And we can thank Clarke and Kubrick for an excellent representation of how this would look in 2001: A Space Odyssey.

There's another good example about 40 seconds into this clip.

Quote from: Spaceship

"You may now exit the, uh, me"

"That's what she said."

Is it cold in here? · « **Reply #62 on:** 31 Jan 2012, 06:39 »

http://en.wikipedia.org/wiki/Momentum_wheel

Motor-generator with a flywheel.

J · « **Reply #63 on:** 31 Jan 2012, 06:44 »

the perspective in panel 3 makes marten look about 30ft tall.

jwhouk · « **Reply #64 on:** 31 Jan 2012, 06:45 »

Quote from: CompSarge on 31 Jan 2012, 00:58

Quote from: jwhouk on 30 Jan 2012, 19:24
The game has officially changed.

I think I know what I'm getting my friend for a present... (I got her hooked on QC and she LOVES Pintsize...)

My only question is - WHICH ONE DO I GET?

EDIT: The answer was easy - WINSLOW.

J · « **Reply #65 on:** 31 Jan 2012, 06:46 »

as to the docking thing, i seem to recall seeing them do it in a somewhat plausible way on babylon 5 once, where a small ship flew into the docking bay, synchronized it's rotation with the station, and waited for a set of extendable clamps to pull it in toward the deck.

of course i only remember it because the ship ended up flying out of control and crashing into the sides, but nevertheless.

jwhouk · « **Reply #66 on:** 31 Jan 2012, 06:47 »

Quote from: Andy147 on 31 Jan 2012, 01:29

In other news, Marten has overtaken Faye to become "character in most QC strips" for the first time in ages... at least according to my slightly subjective and undoubtedly inaccurate count, that is...

I saw that - incredible that it's not all about Faye anymore, hey?

zmeiat_joro · « **Reply #67 on:** 31 Jan 2012, 06:51 »

Quote from: Is it cold in here? on 31 Jan 2012, 06:39

http://en.wikipedia.org/wiki/Momentum_wheel

Motor-generator with a flywheel.

I know they use electromagnetic/gyroscopic flywheels in navigation, I was wondering how it would scale. The first thing that came to my mind was also flywheels.

Jynto · « **Reply #68 on:** 31 Jan 2012, 07:02 »

There is one huge problem with having different parts of the space station moving and non-moving - friction. Any sliding contact between the two sections, provided it isn't absolutely frictionless, is going to be losing momentum. But I'm sure they'll have found a way to make frictionless sliding contacts in the QCverse. And I bet it involves lube.

And what are the odds that Apple tries to sue Jeph or TopatoCo for selling something in the image of an iPod? Hopefully TopatoCo is low-profile enough not to matter to a giant like Apple, who have largely abandoned the image of the click-wheel iPod anyway. On the other hand, they seem to be suing everyone lately. At worst they could force Jeph to write Winslow out of the comic, or just replace his chassis with one of those green Androids.

jwhouk · « **Reply #69 on:** 31 Jan 2012, 07:11 »

And now - what WILL we see on Space Station Hannerdad?

HannerDad, of course.    - 49 (25.9%)
Richard Branson.    - 3 (1.6%)
Stephen Hawking.    - 9 (4.8%)
Robots. Lots and lots of Robots.    - 29 (15.3%)
AnthroPC AI #000001.    - 21 (11.1%)
Birthday cake.    - 17 (9%)
Marigold puking over everything.    - 9 (4.8%)
Transformers.    - 0 (0%)
Waffles.    - 4 (2.1%)
Cookies.    - 1 (0.5%)
Pod Bay Doors.    - 11 (5.8%)
Patrick Stewart.    - 7 (3.7%)
William.... SHATNER!    - 17 (9%)
Bruce Boxleitner.    - 3 (1.6%)
John Cleese.    - 9 (4.8%)
Robert Hays (I KNEW I forgot one...)    - 0 (0%)

Total Voters: 65

Milesb · « **Reply #70 on:** 31 Jan 2012, 07:18 »

On one hand I'd love Winslow and maybe Pintsize to change appearance - perhaps into humanoid chassis' or even just a partial change - but it's fraught with difficulty. It would be hard for Pintsize to be Pintsize if he was in a humanoid chassis - the change in Momo after changing to a full body was pronounced, and she's a much more reserved character than Pintsize.

Mr. Doctor · « **Reply #71 on:** 31 Jan 2012, 07:36 »

Quote from: Akima on 31 Jan 2012, 00:56

Learn physics with Hannelore! I wonder if she'll explain that they're not in zero gravity, but in free fall...

Ah dang. This is one of the times I just know what happened... I know the reason is somewhere in the back of my head but I can't find it anywhere.

Could you explain what exactly happened?
Damn... I feel bad, I did very well in physics just a year ago.

pwhodges · « **Reply #72 on:** 31 Jan 2012, 07:40 »

Without gravity to slow his jump, he hit the other end of the shaft as hard as if (say) he'd run into a wall.

Mr. Doctor · « **Reply #73 on:** 31 Jan 2012, 07:57 »

Oooh yeah you are right. Thanks a lot!
But if they are in free fall... How would the scenario look like if they were in zero gravity? He could jump without problems then?

Deadlywonky · « **Reply #74 on:** 31 Jan 2012, 08:17 »

He still has the same mass though, therefore unless atmospheric drag can slow him sufficiently then he will still hit the wall. in this respect, '0g' and 'free fall' mean the same, as there is nothing attracting Marten to one wall/floor/ceiling of the space station, thereby reducing his momentum.

Milesb · « **Reply #75 on:** 31 Jan 2012, 08:27 »

thanks for that Deadlywonky, I was struggling with explaining that myself.

For our purposes (as I understand it) Zero G and Free fall are often used interchangeably. I've read that there's no such thing as true zero G - there's always some form of gravity (no matter how infinitesimally small) - but I think the right term for Marten and co is free fall.

I think it's to do with frames of reference really; a person in a space craft is often described as in free fall, where as the concept of a person in a space suit outside would often be described as in zero G.

Edit: Though this is my understanding of it, I'm no expert and would welcome some more informed information!

DrPhibes · « **Reply #76 on:** 31 Jan 2012, 08:39 »

Charlie and the Chocolate Factory much?

I like it.

Edit: I'm so far the only one to see the resemblence to the scene where charlie and his grandpa eat the weightless candy and go up in a room such like that?! They do come down and survive but they are the only ones NOT kicked out for doing something they weren't supposed to.

Mr. Doctor · « **Reply #77 on:** 31 Jan 2012, 09:01 »

Thank you guys.

Science is fun!

Omega Entity · « **Reply #78 on:** 31 Jan 2012, 09:27 »

Quote from: DrPhibes on 31 Jan 2012, 08:39

...but they are the only ones NOT kicked out for doing something they weren't supposed to.

Because that wasn't the test

Carl-E · « **Reply #79 on:** 31 Jan 2012, 09:31 »

Free fall is a way of experiencing zero G's. In free fall, you're within something that is falling freely under gravitational pull, and so the reference frame has no pull (see "vomit comet"). Another way is to get far enough away from things exerting gravitational pull, so that the effective pull rounds down to zero. Or you can go to a gravitational balance point (LaGrange points), of which there are about 5 locally IIRC.

HiFranc · « **Reply #80 on:** 31 Jan 2012, 09:39 »

It looks like Marten will have a neck brace to accompany him to the party.

tjradcliffe · « **Reply #81 on:** 31 Jan 2012, 09:48 »

Quote from: pwhodges on 31 Jan 2012, 07:40

Without gravity to slow his jump, he hit the other end of the shaft as hard as if (say) he'd run into a wall.

Thanks, I was embarrassingly confused by this: I assumed Marten was in a tube leading to the outer part of the station and didn't understand why he wasn't hit by the wall on the way down as the station rotated.

Many years ago I worked out the math of "spin-diving": skydiving on an O'Neill Colony (https://en.wikipedia.org/wiki/Space_habitat), which is kind of a fun exercise in combining the physics of rotating reference frames with fluid dynamics. It turns out that under some reasonable assumptions (1/2 g on the outer rim, some clever changes in orientation just before you hit) you can spin-dive from the axis to the surface without any additional gear.

The path you take is a kind of broken spiral: because aerodynamic drag goes as v**2 you basically "fall" outward until the tangential wind picks up, which throws you sideways on a path that becomes more radial as you get further from the axis, and this process repeats itself until you go splat on the surface. The trick is to star-fish with your back to the wind as you get near the surface, maximizing your drag and bringing your tangential speed up. You still have to land running under most reasonable scenarios, but it's the tangential rather than the radial velocity that is the problem.

Skewbrow · « **Reply #82 on:** 31 Jan 2012, 10:26 »

What happened to Marten could be perhaps best emulated in RL in a skating rink. If a skater trips in a way that the blades no longer make contact with the ice, s/he will continue to travel at the same speed in the same direction sliding on nearly frictionless ice (you need to use the blades or something similar to exert friction or other forces to the ice). Of course, even a smooth wet ice is not completely frictionless, so you will be slowing down, but if the fallen skater is going head first to the boards serious injuries may result. Conservation of momentum and all that.

Throg · « **Reply #83 on:** 31 Jan 2012, 10:44 »

Which begs the question: just how much force can a skinny indie young man generate with a jump straight up?

At any rate Marten just got schooled in the difference between leg strength and arm strength.

Edited to add: just realized from panel 4 that Marten is *damn* flexible. Even in full collision, that's a hell of a body position for someone who's not an advanced yoda practitioner.

DSL · « **Reply #84 on:** 31 Jan 2012, 10:48 »

Reports from places like Skylab (very roomy inside; it started life as a fuel tank, after all) indicate: Less force than you'd think to get yourself going, more than you'd think to stop. In less technical terms: Ow.

Milesb · « **Reply #85 on:** 31 Jan 2012, 11:08 »

I guess your legs are used to holding up the weight of your body under normal earth gravity - your arms generally aren't. It would make sense that people would propel themselves forward with their legs too hard when they first got into space..

Mad Cat · « **Reply #86 on:** 31 Jan 2012, 11:09 »

Dumb mass!

C'mon. Someone hadda say it.

ecstaticjoy · « **Reply #87 on:** 31 Jan 2012, 12:53 »

eeeeeeeeeeeeee

Redball · « **Reply #88 on:** 31 Jan 2012, 13:37 »

Wouldn't Marigold have been more comfortable if she'd held on to something instead of floating topsy-turvy? Hanners might have told her to grab the rungs if she hadn't been distracted.

Skewbrow · « **Reply #89 on:** 31 Jan 2012, 13:53 »

DSL has got it right, me thinks. IIRC the Skylab-astronauts practiced doing a mid-air tumble/somersault so that they would also land legs first at the other end. Controlling your rotation is also tricky, but at least you can extend your body to slow down the rotation or wrap your arms around your legs (as in a diver's tuck position) to speed up the rotation.

Poor Marten probably didn't even realize the need to brace for impact.

Akima · « **Reply #90 on:** 31 Jan 2012, 14:10 »

Quote from: WAYF on 31 Jan 2012, 04:42

2) Marigold has some sort of square yet skin-shaped patch on her neck. Is that how her medicine was administered, and is all medicine administered like that in the QC universe?

Transdermal scopalamine patches have been used to control motion sickness for years. There is nothing to see here, move along.

Hannelore, the experienced high-frontier resident, follows the old maxim "One hand for yourself, one for the ship". And she can obviously move very quickly in a free-fall environment.

Quote from: Carl-E on 31 Jan 2012, 09:31

Free fall is a way of experiencing zero G's.

I give up...

DSL · « **Reply #91 on:** 31 Jan 2012, 15:55 »

Quote from: Akima on 31 Jan 2012, 14:10

Hannelore ... can obviously move very quickly in a free-fall environment.:

She might have a familiar motivation.

Comrade · « **Reply #92 on:** 31 Jan 2012, 16:07 »

Jeph has just got to make a t-shirt related to 'you still have all your mass'.

Welu · « **Reply #93 on:** 31 Jan 2012, 16:18 »

I'm enjoying this week's comics but unfortunately I don't feel smart enough to really comment on the physics and such discussions in the forums.

berf

Kugai · « **Reply #94 on:** 31 Jan 2012, 16:32 »

Congratulations Mr. Reed, you have just given us a new visual definition fo the term Faceplant.

DSL · « **Reply #95 on:** 31 Jan 2012, 17:18 »

Marten's going to find this rather difficult without his helmet.

Redball · « **Reply #96 on:** 31 Jan 2012, 18:23 »

Quote from: Welu on 31 Jan 2012, 16:18

I'm enjoying this week's comics but unfortunately I don't feel smart enough to really comment on the physics and such discussions in the forums.

berf

I'm enjoying the comment about the science as well as the art. Even when commenters aren't sure of the science, the conversation is entertaining, instructive, helpful, not mean-spirited.

akronnick · « **Reply #97 on:** 31 Jan 2012, 20:06 »

Quote from: DSL on 31 Jan 2012, 17:18

Marten's going to find this rather difficult without his helmet.

Maybe he should take a stress pill, and we can talk about this...

gangler · « **Reply #98 on:** 31 Jan 2012, 20:50 »

It never occurred to me until I read this update to consider the implications of zero gravity. Martin is completely weightless. Weight as a variable has been completely removed from the equation. His momentum is now due to his mass. This establishes mass and weight to be two separate variable when calculating momentum. Information that's relevant when designing any form of projectile. By nature of having set foot outside of our planets gravitational field we're now able to launch things with more precision. It probably also effected the development of things like aircrafts.

Not like I wasn't aware of the individual facts. I've just never connected them to eachother like that. I don't think I ever really realized how these things relate to eachother before.

iduguphergrave · « **Reply #99 on:** 31 Jan 2012, 21:03 »

I like turtles.

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Author Topic: WCDT 2111-2115 (Jan 30 - Feb 3, 2012) - QC in SPAAAAAAACE!!! Week 2! (Read 72698 times)

Comrade