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SeiKeo
September 18th, 2011, 03:50 PM
http://kerbalspaceprogram.com/

DL link: http://kerbalspaceprogram.com/download.php

What is this game?


http://www.youtube.com/watch?v=9WjZJFK9wXo

Basically, that.


http://www.youtube.com/watch?v=y8TUus3CB48

Or that.

Your goal is to get your brave Kerbalnauts into space, on top of a jury rigged contraption of rockets, fuel tanks, with hope holding it all together. Crew survival and return not required.


It. Is. Fun. As. Hell.


Also, grab this: http://mod.gib.me/kerbal/mods/Sunday Punch/ It's a parts package to add to the lacking selection in the base game. Just take the files in the zip and put them in the Parts folder of KSP.

Ivan The Mouse
September 18th, 2011, 03:56 PM
Ah, I've created my Kaguya-class rocketship in that game. Good times.

Mike1984
September 18th, 2011, 05:31 PM
I can't seem to get my spaceship to actually do anything. I press "space" to launch it, and it just doesn't fire....

SeiKeo
September 18th, 2011, 05:33 PM
Is the first stage, the thing at the bottom of the stack list, an engine?

Mike1984
September 18th, 2011, 08:28 PM
I'm not stupid, you know....

But, I found the problem anyway. I was using one of the extra parts, and it didn't seem to work properly. The rocket works now. Although, I tried to build an insanely big one, and it just isn't stable enough....

Five_X
September 18th, 2011, 08:57 PM
Use your physics mojo, Mike! You should be able to hit the moon in no time with your kind of know-how!

MZeroX
September 18th, 2011, 09:00 PM
irl physics and game mechanics differ, in general.

just saying, still in the process of attaining this game. was pretty sure there was already a thread about this. maybe it was just a post in the games rec thread, or something from the old forum.

Five_X
September 18th, 2011, 09:07 PM
You lie, everything I learn in video games applies to real life, and vice versa.

SeiKeo
September 18th, 2011, 09:14 PM
Use your physics mojo, Mike! You should be able to hit the moon in no time with your kind of know-how!

KSP HAS NO MOON

Five_X
September 18th, 2011, 09:14 PM
THAT'S NO MOON

Mike1984
September 18th, 2011, 09:15 PM
Use your physics mojo, Mike! You should be able to hit the moon in no time with your kind of know-how!

Well, I got to nearly 100 km up with my first serious effort. It's hard to get any higher, though, because there aren't the right parts to build a truly massive rocket.


irl physics and game mechanics differ, in general.

just saying, still in the process of attaining this game. was pretty sure there was already a thread about this. maybe it was just a post in the games rec thread, or something from the old forum.

The physics of the game does seem pretty reasonable, actually. The problem is that there simply aren't the necessary components to make it stable.

SeiKeo
September 18th, 2011, 09:16 PM
Well, I got to nearly 100 km up with my first serious effort. It's hard to get any higher, though, because there aren't the right parts to build a truly massive rocket.

Here. http://mod.gib.me/kerbal/mods/ Mega collection of extra fanmade parts, enabling even more dangerous rockets!

Mike1984
September 18th, 2011, 09:30 PM
Well, I had the Sunday Punch ones already. The problem with them, though, is that there aren't any connectors for the large engines and fuel tanks. So, when I tried to stick four large engines on the bottom, it just falls apart....

SeiKeo
September 18th, 2011, 09:35 PM
Oh, yeah, that. Happens to me too for some reason sometimes: no clue why. I've gotten this to work though.

http://i1128.photobucket.com/albums/m492/LeopardBear/Space_1.png

The engine is four liquid fueled engines, stuck onto a quad coupler. Works decently well, though I haven't gotten it into an orbit yet.

Mike1984
September 18th, 2011, 09:46 PM
Yeah, mine was a lot taller than that. That one reminds me of my first effort, although I had one less large fuel tank and the solid rocket boosters were attached to the top section and fired after the main engines had stopped.

I couldn't get it to orbit, though, although only because I lack the practical skills to make the rocket not spin all over the place....

SeiKeo
September 18th, 2011, 09:47 PM
Yeah, the issue that I'm having with large rockets is that I find them pretty much uncontrollable after a point: if they start tipping, you're screwed. Apparently throwing more SAS modules on might help, so I'm going to try that.

EDIT: Right, new rocket... may have worked. I'm at 1700 m/s and falling, but 460 Km and rising, so I'm going to let it go for a bit and see what happens.

Mike1984
September 18th, 2011, 10:38 PM
Well, that should certainly be enough to get you into orbit, I think. All you need for that is enough horizontal velocity to "miss" the planet (I could do an exact calculation if you wanted, but that would be a waste of time...).

The issue I have with big rockets is that the joint between the two sections is not strong enough, so if you run the main engines at full throttle they actually break the connection and blow up the entire rocket.

Erlkonig
September 18th, 2011, 10:40 PM
Holy fuck looks awesome.

SeiKeo
September 18th, 2011, 10:44 PM
Well, that should certainly be enough to get you into orbit, I think. All you need for that is enough horizontal velocity to "miss" the planet (I could do an exact calculation if you wanted, but that would be a waste of time...).

The issue I have with big rockets is that the joint between the two sections is not strong enough, so if you run the main engines at full throttle they actually break the connection and blow up the entire rocket.

Yeah, there are people who made calculators for the orbits and stuff. The connector issue I don't seem to have, but that's probably because my designs are mostly just simple linear stacks.

EDIT: This is brilliant.


http://www.youtube.com/watch?v=Bm0yNKl51rs

Five_X
September 19th, 2011, 01:03 AM
I want to make a plane. It is harder than it looks.

Getting outta orbit's not that bad, though.

SeiKeo
September 19th, 2011, 01:05 AM
Spaceplanes are hard, verily. Plus, I'm probably just too lazy, but I don't have a parts package with proper wings.

Five_X
September 19th, 2011, 01:07 AM
There are OTHER parts packages!?

SeiKeo
September 19th, 2011, 01:10 AM
Which one do you have? Because yeah, there's a few, and individual parts.

Five_X
September 19th, 2011, 01:13 AM
I just have the one you linked to in the OP.

SeiKeo
September 19th, 2011, 01:16 AM
Ah. You're just using the little winglets, right?

Five_X
September 19th, 2011, 01:22 AM
Yep, those and these other ones that actually work sometimes because they can move a bit.

Mike1984
September 19th, 2011, 05:14 AM
Well, the thing is, to do a proper spaceplane, you would need a jet engine. Fitting a rocket to the back of a plane is pointless, because once you're in space the wings are entirely superfluous (except for landing, of course). So, all you've got there is a space shuttle, really....

Erlkonig
September 19th, 2011, 05:40 PM
Well, the thing is, to do a proper spaceplane, you would need a jet engine. Fitting a rocket to the back of a plane is pointless, because once you're in space the wings are entirely superfluous (except for landing, of course). So, all you've got there is a space shuttle, really....

Nonsense! I travelled across the world in a rocket!

...With a lot of fuel.

Mike1984
September 19th, 2011, 05:50 PM
Well, I seem to have hit escape velocity. But, unfortunately, I lack the fuel necessary to come back, so my poor Kerbalnaults are now floating slowly off into deep space....

SeiKeo
September 19th, 2011, 05:52 PM
Wheeeeeeee~


Yeah, that's how most of my attempts end also. Either, an attempt to get orbit fails and deorbits, or too much acceleration and we go on foreveeeeeerrrrrr...

Mike1984
September 19th, 2011, 05:59 PM
Well, I think I'm going to try it again with a small rocket stuck on the ship so it can fly back, because I'm only just over escape velocity, I think.

Mike1984
September 19th, 2011, 08:21 PM
Woo, I got into orbit (I think, anyway, I didn't have the time to wait around to be sure), and back out of it again.

The game doesn't like my rocket, though. It runs ridiculously slowly when I try to launch it, probably because I have about 60 of the little struts holding it together and it has to do the physics for all of them.

Mcjon01
September 20th, 2011, 12:49 AM
Aww, I thought I had lucked into orbit, but it seems to be decaying. At a rather alarming rate, now. Sorry, moon men, I probably should have given you guys a parachute.

Five_X
September 20th, 2011, 01:56 AM
I feel like recording a video of a flight with fraps, then putting David Bowie's Space Oddity overtop of it.

Because really, just think, when your poor Kerbals are stuck in space forever after you launch them up there and can't bring them back...

Mike1984
September 20th, 2011, 05:05 AM
Aww, I thought I had lucked into orbit, but it seems to be decaying. At a rather alarming rate, now. Sorry, moon men, I probably should have given you guys a parachute.

What sort of altitude were you at?

Hoster
September 20th, 2011, 06:26 AM
So...

200,000 meters and counting. I don't think my Kerbals are coming home anytime soon.

Maybe I should have built some kind of thrusters to get back.

Mike1984
September 20th, 2011, 06:38 AM
Only 200,000? I gone mine to several million km before I gave up. :p

Also, at 200,000, you could still fall back, potentially. It depends how fast you're going. In fact, I got into an orbit at that altitude....

Hoster
September 20th, 2011, 06:55 AM
Only 200,000? And counting.

Besides, it was not a mission to Mars, I just hoped to get into orbit. Since the craft kept on going at a good speed I concluded that I would miss orbit and go out into the black beyond at that rate, so I ended it there.

Mike1984
September 20th, 2011, 07:13 AM
Well, it depends how fast you're going. It's quite possible that you were going fast enough to get very high, but hadn't quite reached escape velocity. 200,000 km isn't really that high at all, TBH.

But, regardless, to get into orbit you need to be moving horizontally, not vertically, so if you weren't adding any horizontal motion you're not going to reach orbit.

Mcjon01
September 20th, 2011, 08:03 AM
What sort of altitude were you at?

I peaked at about 380,000 meters altitude. Motion was almost entirely horizontal at that point, and I made a lap (or two?) around the planet before I started really falling. However far millions of kilometers translates to. Ah, but I should have known it was too much to hope for orbit on my first try.

The funny thing was how two of the astronauts were rightfully losing their shit, while the guy in the middle was having the time of his life.

Erlkonig
September 20th, 2011, 08:50 AM
I peaked at about 380,000 meters altitude. Motion was almost entirely horizontal at that point, and I made a lap (or two?) around the planet before I started really falling. However far millions of kilometers translates to. Ah, but I should have known it was too much to hope for orbit on my first try.

The funny thing was how two of the astronauts were rightfully losing their shit, while the guy in the middle was having the time of his life.

Yeah, that usually happens.


Only 200,000? I gone mine to several million km before I gave up.

Several million Km? Mike, the game doesn't even compute such a number. The max is, 999999K, I think?

SeiKeo
September 20th, 2011, 09:42 AM
I think it might roll over to megameters or something like that.


The funny thing was how two of the astronauts were rightfully losing their shit, while the guy in the middle was having the time of his life.

http://ksp.victorbjelkholm.se/wp-content/uploads/2011/07/anyoe.png

Mike1984
September 20th, 2011, 10:16 AM
I peaked at about 380,000 meters altitude. Motion was almost entirely horizontal at that point, and I made a lap (or two?) around the planet before I started really falling. However far millions of kilometers translates to. Ah, but I should have known it was too much to hope for orbit on my first try.

The funny thing was how two of the astronauts were rightfully losing their shit, while the guy in the middle was having the time of his life.

Really?

380,000 m should be plenty high enough for a stable orbit. Are you sure you actually did orbit the planet?


Several million Km? Mike, the game doesn't even compute such a number. The max is, 999999K, I think?

Sorry, I meant several million metres (i.e. several thousand km). Although, I think the game can actually cope with millions of km, it just rolls over again like it does when going from counting in m to counting in km.

Mcjon01
September 20th, 2011, 10:46 AM
Oops, yeah, I meant meters, too. Not kilometers lol. And I'm pretty sure I went from light to dark to light to dark again, but I wasn't paying too much attention. The simulation ran for half an hour after I finished all the launch stages so it got boring to watch, and all I know for sure is that I ended up in the middle of a giant ocean.

The capsule was hardly stable, though. More like, violently gyrating in every direction.

Mike1984
September 20th, 2011, 11:05 AM
Oops, yeah, I meant meters, too. Not kilometers lol.

I had assumed that's what you meant, actually. I just made a cock-up with my response.


And I'm pretty sure I went from light to dark to light to dark again, but I wasn't paying too much attention. The simulation ran for half an hour after I finished all the launch stages so it got boring to watch, and all I know for sure is that I ended up in the middle of a giant ocean.

Well, I ran for longer than that, and I'm pretty sure I hadn't managed to orbit the planet completely in that time. It's hard to tell, though.

But, unless the physics engine is broken, it should not be possible to get to that altitude, orbit the planet once and then fall back to Earth without any further input. Gravity simply does not work that way, and the atmosphere that high up is thin enough that it takes years for an orbit to decay.


The capsule was hardly stable, though. More like, violently gyrating in every direction.

Doesn't matter. As long as the rocket isn't firing and you're outside the atmosphere you can rotate as much as you like and it won't make the slightest bit of difference. There's no air up there, and thus drag isn't an issue.

Mcjon01
September 20th, 2011, 11:15 AM
Haha, well, next time I'll be sure to keep better track of what's going on, my report is probably extraordinarily flawed. First step is to get better at piloting so that I'm not doing gut-churning barrel rolls and propelling myself toward the planet in the last few stages of flight. I was just so excited that my rocket made entirely of fuel tanks and liquid boosters didn't blow itself up!

Hoster
September 20th, 2011, 11:22 AM
Man, why can't I ever hit that damnable Space Center with my Rockets?!

Erlkonig
September 20th, 2011, 11:25 AM
Man, why can't I ever hit that damnable Space Center with my Rockets?!

I managed, once.

But yeah, it's hard as hell.

SeiKeo
September 20th, 2011, 11:27 AM
Define hit, because I've managed to hit it by blowing up quite a few rockets on the pad. :D

Mike1984
September 20th, 2011, 11:29 AM
Haha, well, next time I'll be sure to keep better track of what's going on, my report is probably extraordinarily flawed.

Yeah, lol.

To be fair, I may have done the same, in that I thought I'd orbited, but when I came back down due to boredom (I actually had fuel left, and specifically did a de-orbit burn which took me down fast, so I think I was genuinely in orbit) I had seemingly not really travelled that far. I do believe I was genuinely in orbit, though, because my vertical velocity was near zero and I was going 2000 m/s horizontally (which was about right for a circular orbit at that altitude).


First step is to get better at piloting so that I'm not doing gut-churning barrel rolls and propelling myself toward the planet in the last few stages of flight.

Well, if you were doing that, then you were almost certainly not orbiting, because you don't get a significant horizontal velocity by accident....


I was just so excited that my rocket made entirely of fuel tanks and liquid boosters didn't blow itself up!

Lol, I see....


Man, why can't I ever hit that damnable Space Center with my Rockets?!

That's easy, you just crash into the launchpad....

Satehi
September 20th, 2011, 11:43 AM
I think he's talking the Vehicle Assembly Building, in which case I think it would be easy just using a SRB and those wing thingies, not sure if they help.

Mike1984
September 20th, 2011, 11:56 AM
I think he's talking the Vehicle Assembly Building, in which case I think it would be easy just using a SRB and those wing thingies, not sure if they help.

Well, what you really need is a way to make your rocket fly horizontally from the start. That's pretty hard to do, though....

Erlkonig
September 20th, 2011, 12:13 PM
Define hit, because I've managed to hit it by blowing up quite a few rockets on the pad. :D

He means the Vehicle Assembly Central.

Mike1984
September 20th, 2011, 12:15 PM
I'm now thinking of how to produce a missile....

It'd have to be a suicide missile, though, unfortunately, and unless you orbit the planet there aren't really any targets to hit....

Satehi
September 20th, 2011, 12:24 PM
SRB's continue to fly after being ejected.

Following that, I think it should be possible, using a fuel tank with liquid engine and a couple SRB's with the ejection order customized to launch missiles. The flaps would probably help.

Mike1984
September 20th, 2011, 12:25 PM
SRB's continue to fly after being ejected.

Following that, I think it should be possible, using a fuel tank with liquid engine and a couple SRB's with the ejection order customized to launch missiles. The flaps would probably help.

Yes, but since you can't follow them, you would have no way of telling what, if anything, they had actually hit.

Hoster
September 20th, 2011, 12:34 PM
Well, it's only fun if you get some altitude before you do it....

Five_X
September 20th, 2011, 05:42 PM
I loaded up KSP this morning and launched a ship into space, got it out of the atmosphere and watched it keep on hurtling along away from Kearth. I decided, then, to leave the program on and see how far I could get.

Currently, about 5 1/2 hours from takeoff, I'm over 150,000 km away from the pale blue dot (http://www.youtube.com/watch?v=MnFMrNdj1yY) that is home, hanging like a mote of dust.

Five_X
September 20th, 2011, 08:38 PM
Over 220,000 kilometers now. In a few hours I'll have traveled the distance between Earth and the Moon. Go me.

Hoster
September 21st, 2011, 12:33 AM
Is there any point where your speed stops decreasing in this game?

Five_X
September 21st, 2011, 12:50 AM
There seems to be. I'm at... *checks* 332,000 km up, and my speed has barely changed (only by a couple decimal points) over the last few hours. So technically, your speed will stop decreasing eventually, since you're in space and there's nothing really to slow you down.

At this distance, I can actually no longer see Kearth. Then I realized: I'm heading for the Sun.

Yep, these poor Kerbalnauts aren't going to end up stranded in deep space, no, they'll die from any number of causes relating to the sun and its heat and radiation.

I also have a question for those more well versed in astronomy than I: at what point, traveling from the Earth, would the Earth itself be too small to see? Because I'm trying to figure out what the scale is of KSP's space area. In real space, at 300K+ kilometres up, one wouldn't even have reached the moon!

Mike1984
September 21st, 2011, 05:11 AM
Is there any point where your speed stops decreasing in this game?

No, but it will decrease more and more slowly as you get further out.

Given your current (vertical) speed and altitude, it's possible to work out the speed you'll asymptote towards as you get towards infinity.


There seems to be. I'm at... *checks* 332,000 km up, and my speed has barely changed (only by a couple decimal points) over the last few hours. So technically, your speed will stop decreasing eventually, since you're in space and there's nothing really to slow you down.

Well, it's simple physics. The further out you get, the smaller the gravitational force on your ship is. By the time you're that far up, the force is pretty negligible (relative to the force on the surface, that is...), so you won't decelerate particularly fast.

That far up, the gravitational force would be about 1/2500 g (since you're 50 Earth radii away), so you should be decelerating at about 1/250 m/s^2. So, in an hour, your speed should drop by about 16 m/s.


At this distance, I can actually no longer see Kearth. Then I realized: I'm heading for the Sun.

Yep, these poor Kerbalnauts aren't going to end up stranded in deep space, no, they'll die from any number of causes relating to the sun and its heat and radiation.

In the current version of the game, the "sun" is apparently just a drawing on the background, so I'm pretty sure it's impossible to reach it.


I also have a question for those more well versed in astronomy than I: at what point, traveling from the Earth, would the Earth itself be too small to see? Because I'm trying to figure out what the scale is of KSP's space area. In real space, at 300K+ kilometres up, one wouldn't even have reached the moon!

Are you sure that the Earth is invisible, as opposed to you just not being able to find it (I've had that issue)? Because I'm pretty sure that a) Kerbal is supposed to be the same size as Earth (so people can work out orbital velocities etc.) and b) you could definitely see the Earth from that altitude.

Erlkonig
September 21st, 2011, 07:31 AM
a) Kerbal is supposed to be the same size as Earth

No.

Earth's radius is 3,378Km

Kerbin's radius is 600Km.

Also don't confuse the Kerbal with the planet Kerbin.

Mike1984
September 21st, 2011, 07:42 AM
No.

Earth's radius is 3,378Km

Kerbin's radius is 600Km.

What makes you think this?

If it's true, then it makes working out orbital velocities, escape velocities etc. a lot more awkward, especially if the mass isn't also given. Although, technically, you could work it out by looking at the rate of deceleration at various altitudes....


Also don't confuse the Kerbal with the planet Kerbin.

OK, whatever....

RoadBuster
September 21st, 2011, 09:14 AM
Kerbin:



Radius: 600.06 km



Circumference: 3770km



Gravity at sea level: 9.80665 m/s^2



Mass: 5.29e22 kg



Gravitational parameter (http://en.wikipedia.org/wiki/Standard_gravitational_parameter): 3.531100e3 km^3/s^2



Escape velocity (http://en.wikipedia.org/wiki/Escape_velocity): 3.430620 km/s (from Kearth surface)



Axial tilt: nonzero, specific degree unknown.



Rotation: currently zero, will rotate in future versions


From the Website's Wiki

Mike1984
September 21st, 2011, 09:30 AM
Ah, OK.

Well, that makes things a little different, in terms of the orbital heights at least.

Erlkonig
September 21st, 2011, 09:30 AM
What makes you think this?

It's in the wiki.


If it's true, then it makes working out orbital velocities, escape velocities etc. a lot more awkward, especially if the mass isn't also given. Although, technically, you could work it out by looking at the rate of deceleration at various altitudes....

It's in the wiki as well.

I guess not everyone tries to do all those calcs Mike?

After all, I just try to make BIG ROCKET. BIG ROCKET FLY FAST, BIG ROCKET FLY LONG.

Mike1984
September 21st, 2011, 09:46 AM
It's in the wiki.

Fair enough. I had just assumed it was the same as the Earth. But, I guess it does make sense for it to be smaller (approximately a tenth of the radius of the Earth, in fact), since it means that everything happens more quickly....

I suspect that, in fact, I hadn't noticed it for that reason. Because it was a tenth of the value, I was just missing the factor of ten in the altitude....


I guess not everyone tries to do all those calcs Mike?

Well, if you want to get into orbit, you need to, really.


After all, I just try to make BIG ROCKET. BIG ROCKET FLY FAST, BIG ROCKET FLY LONG.

Yeah, but once you've hit escape velocity, just flying up forever gets rather boring. It's a lot more fun (and a lot more challenging) to try to actually get into orbit.

SeiKeo
September 21st, 2011, 09:48 AM
I know people have worked out the orbital speeds etc, just don't have the link on me right now. It was in the KSP thread on Something Awful though, so look on the OP there.

Mike1984
September 21st, 2011, 09:58 AM
I know people have worked out the orbital speeds etc, just don't have the link on me right now. It was in the KSP thread on Something Awful though, so look on the OP there.

Yeah, they have.

But, the radius is (approximately) 1/10th of the radius of the Earth and the gravitational force at the surface is the same, so as long as you divide all the heights by 10 you should get the same result as you would for the Earth itself. The only exception would be the escape velocity, and that should scale with the radius, though, so for Kerbin it would be 1/10th of what it would be for Earth.

Five_X
September 21st, 2011, 12:08 PM
http://i751.photobucket.com/albums/xx152/Fivexxxxx/KSP2011-09-2109-05-39-10.jpg

I ended the mission here. I traveled far beyond the distance between the Earth and Moon, kept going, and eventually Kerbin became invisible, totally impossible to see, leaving my Kerbalnauts still on their inevitable doom in the fire and radiation of the Sun.

Mike1984
September 21st, 2011, 12:34 PM
Well, given the reduction in radius compared to what I thought, that seems somewhat more plausible. But, even so, are you sure it is invisible, as opposed to just small and off-screen?

Five_X
September 21st, 2011, 06:27 PM
I am completely sure.