Kerbals in Spaaaaace!

[AMX]

I managed to land on the Mun in the demo, but didn't have enough fuel to return.
I think I'll leave it at that until the game is finished...

Also, my officially last attempt to convince Impnemo:

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Phrases and clauses and such like that can be tricky.

An equitable sharing by all States Parties in the benefits derived from those resources, whereby the interests and needs of the developing countries -clause- shall be given special consideration

The clause youre bringing up isnt saying that the sharing must be especially directed towards those doing the work, rather, special consideration must be made for the countries who arent able to in addition to those who are.

Tricky enough that you're misreading it.
It's not "those who can't, as well as those who can" (i.e. everybody) - it's "those who can't, as well as those who do."
Which leaves out people who could, if they wanted - exactly the ones who need to be motivated...

Given the time it was put in place, and the rampant anti-colonial fervor of that time, its a hedge against the USA and the USSR to prevent them from using resources in space while most of the world still went without electricity or running water. As long as the hedge is in place, it is going to continue to prevent development.

Prevent?
No.
"Inhibit" maybe, but it's explicitly meant to allow making a profit.

In either event, yes, taking the profit and sharing it by any method means you are not making the profit for yourself. Starkist/Chicken of the Sea dont "share" their profit earned from Tuna fishing in international waters with everyone who has a common heritage with the ocean. They reap the full reward of their own labor. They being employees and shareholders.

You forgot taxes.
Which mostly benefit other people... but somehow, that hasn't stopped fishing...

This despite the fact that there must be limits on their labor to prevent a collapse of the Tuna stock. Thats the "tragedy of the commons" that you, and more importantly they, would want to avoid. As a rule you don't eat your own seed grain, but when its common different forces come into play.

If they are in it for the long haul, and believe that everybody else fishing in the same area is just as diligent as them...
For some reason, it's not working as well as you seem to think.

[Trekkin]

Finished, AMX? How do you mean?

As far as I know (and if I've got this wrong, someone please tell me) the basic physical model is done; at least for the short-to-mid-range future I believe the developers are looking at implementing more flight planning and reversion logic as part of bringing career mode online. There's also the normal flow of new parts and fixes to old parts, but I think the way the game handles rockets moving in space is done.

[Artanis]

So I broke down and got the game. I've been using the Scott Manley tutorial videos, and they've been pretty helpful, but in my case, as they say, "you can't fix stupid".

I got into orbit on the first try using the tutorial, did the second try without the tutorial, and am doing a relatively good job of (eventually) getting the periapsis and apoapsis within 20% of each other. Then I tried his second tutorial, Minmus, and...yeah.

Got there on the third try, slammed into the planet. Slammed into it a couple more times along the way to my tenth ******** try, at which point I managed to land. I even got back safely, though I was so low on fuel that poor Jebediah XII had to orbit Kerbin four times as I used minimum-power one-second burns at optimum points to de-orbit, winding up with 0.17 units of fuel when I finally popped my last stage. But hey, he lived (for once)!

Now, on to learning how to make better rockets. As I expected, "swap the engines and fuel tanks for bigger ones" didn't help at all, but I was surprised at how little effect bolting on an extra 2-solid-booster stage had on my launch

[AgentPaper]

SRBs aren't good for getting you extra Delta-V. What they're good for is getting larger rockets off the ground that usually wouldn't be able to because of a low thrust-weight ratio.

The reason they aren't good for delta-V is because you start to lose efficiency the faster you go in atmosphere due to air resistance. Liquid engines usually have a low TWR and thus won't get you fast enough to lose delta-V, but SRBs have much better TWR and can easily send you faster than you should.

To stay efficient, make sure you throttle down your main engine after you're off the launchpad, aiming for 100 m/s speed and low but still positive acceleration. Do this until you reach ~10km, at which point the atmosphere is much thinner and you're free to throttle up and gravity turn and such.

[Eldan]

I'm really overbuilding, it seems. After I finally got my lander to the moon and back, barely, I sent the same lander to another planet with no problem.

Perhaps 20 mainsail engines is too much for my first stage....

[factotum]

To stay efficient, make sure you throttle down your main engine after you're off the launchpad, aiming for 100 m/s speed and low but still positive acceleration.

I usually set my limit at 200 m/s, not 100...if you're going too slowly you burn a lot of fuel just maintaining speed through the lower atmosphere, if you go too fast then air drag losses become significant; I find 200 is a nice sweet spot between the two.

[AgentPaper]

I usually set my limit at 200 m/s, not 100...if you're going too slowly you burn a lot of fuel just maintaining speed through the lower atmosphere, if you go too fast then air drag losses become significant; I find 200 is a nice sweet spot between the two.

Just did a few tests, and there doesn't appear to be much difference between the two. I did both with the same rocket, and they both got to about 32km.

I think this is actually because terminal velocity rises as you get higher and higher. At 1000m, it's 100, but by 10,000m it goes over 200m/s. So, going 100m/s is more efficient at the start, and 200m/s is more efficient at the end.

However, what's really efficient, is to start at 100m/s, and then slowly throttle up to 200m/s by 10,000m, effectively maintaining terminal velocity. Obviously it's tricky to get this just right, but using MechJeb to ensure accuracy I used this method to get the same rocket up to 42km, 10km higher than either of the above methods.

Just for proof, I also did a test a 300m/s, which only got me up to 24km, and at 50m/s, which only got me up to 11km.

Finally, I did a test at 150m/s, which got me up to 38km. So, it seems if you want to be efficient, you can either aim for 150m/s the whole way, or go for 100m/s at the start and slowly ramp that up as you go along.

With some clever engineering, you could probably design a rocket that always has the right TWR to maintain terminal velocity at any given point on it's trajectory while at full throttle. This should be possible, or at least close to it, since your TWR naturally rises as you use up fuel. You'd probably need a short kick to get you up to speed off the pad, which is what SRBs are for.

I might do some playing around later today to see if I can figure out the math for such a thing.

[Artanis]

SRBs aren't good for getting you extra Delta-V. What they're good for is getting larger rockets off the ground that usually wouldn't be able to because of a low thrust-weight ratio.

The reason they aren't good for delta-V is because you start to lose efficiency the faster you go in atmosphere due to air resistance. Liquid engines usually have a low TWR and thus won't get you fast enough to lose delta-V, but SRBs have much better TWR and can easily send you faster than you should.

To stay efficient, make sure you throttle down your main engine after you're off the launchpad, aiming for 100 m/s speed and low but still positive acceleration. Do this until you reach ~10km, at which point the atmosphere is much thinner and you're free to throttle up and gravity turn and such.

For clarity, I took the rocket from Manley's Minmus tutorial and added a couple SRBs that would fire while the liquid engines did nothing, then turn on the liquid engines when I dropped the SRBs. Basically, I took what worked starting from 0m and 0 m/s and did the exact same thing from a starting point of from a thousand or two meters and 80 m/s. However, that only seemed to make things worse, if anything, which was a valuable lesson in just how much I have left to learn.

[AgentPaper]

For clarity, I took the rocket from Manley's Minmus tutorial and added a couple SRBs that would fire while the liquid engines did nothing, then turn on the liquid engines when I dropped the SRBs. Basically, I took what worked starting from 0m and 0 m/s and did the exact same thing from a starting point of from a thousand or two meters and 80 m/s. However, that only seemed to make things worse, if anything, which was a valuable lesson in just how much I have left to learn.

Ah, in that case, your problem is actually going too slow, not too fast. You should fire the main engines along with the SRBs, and maintain terminal velocity as I outlined in my previous post. This should get you a bit of extra delta-V. If you still end up doing worse overall, it's probably due to some inefficiency somewhere else in your maneuvers.

[AMX]

Finished, AMX? How do you mean?

A version number that does not start with "0." would be a good start...

[Artanis]

Yay! Got to Minmus and back without actively watching a tutorial while doing so. Asparagus staging (which I had read up on beforehand) was a massive help in the fuel department: I still had enough in my main tank for 80% of my orbit-Minmus-instead-of-flying-past-it burn*, and when I got back to Kerbin, I had literally two orders of magnitude more fuel left than last time. I then proceeded to waste 90% of that trying to circularize my orbit before saying getting bored and deorbiting, but still.

Also, I learned a valuable lesson when landing: if the altitude isn't changing but your velocity is still at 20 m/s, you will explode upon hitting the ground


*I know there's an official name for this sort of thing, but I can't think of what it is. I want to say "Orbital Insertion Burn", but don't know for sure. I'll probably kick myself once I find out though.

[AgentPaper]

Yay! Got to Minmus and back without actively watching a tutorial while doing so. Asparagus staging (which I had read up on beforehand) was a massive help in the fuel department: I still had enough in my main tank for 80% of my orbit-Minmus-instead-of-flying-past-it burn*, and when I got back to Kerbin, I had literally two orders of magnitude more fuel left than last time. I then proceeded to waste 90% of that trying to circularize my orbit before saying getting bored and deorbiting, but still.[/QUOTE]

Yeah, asparagus is pretty good. Well, staging in general is good, but asparagus is a bit better than pancake for now, since we don't have air resistance. It also allows for much larger rockets, since pancake stacking gets very tall very fast with our current tank sizes. (You can attach them radially, but then you may as well just use asparagus)

Also, I learned a valuable lesson when landing: if the altitude isn't changing but your velocity is still at 20 m/s, you will explode upon hitting the ground

Heh, yeah that horizontal velocity can be a bitch. You should be burning retrograde rather than directly up until you're right above the surface. That should keep horizontal velocity to a minimum.

*I know there's an official name for this sort of thing, but I can't think of what it is. I want to say "Orbital Insertion Burn", but don't know for sure. I'll probably kick myself once I find out though.

That is actually what it's called. I think "capture burn" is also acceptable, but less official.



Also, speaking of Asparagus, I decided to take it to its logical conclusion:

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[Impnemo]

Ah, in that case, your problem is actually going too slow, not too fast. You should fire the main engines along with the SRBs, and maintain terminal velocity as I outlined in my previous post. This should get you a bit of extra delta-V. If you still end up doing worse overall, it's probably due to some inefficiency somewhere else in your maneuvers.

Yes, you shouldnt have an exposed engine on the pad that isnt helping to lift you. Otherwise the engine is just dead weight youre dragging up, which is compounded by all the fuel it would be burning that youre also dragging up. The wiki has a table on stock aerodynamics terminal velocities.

http://wiki.kerbalspaceprogram.com/w...bin#Atmosphere


If youre going slower than the listed speeds youre losing too much to gravity. If youre going faster than the listed speed youre wasting fuel/delta v pushing air around. If you have to throttle down to stay on the ideal ascension profile then you ought to consider changing to less powerful/more efficient engines - say, swap the mainsail for a skipper etc. To determine which engine to use it is helpful to remember the formula for acceleration - a=f/m. Acceleration is force/mass. Conveniently, max engine thrust is given in kilonewtons and mass is in metric tonnage. This allows us to plug the thrust of your engine(s) against the mass of our ship very easily... if you have the engineer add on or dont mind adding all the parts yourself.


As an example, a three part rocket - mainsail rockomax jumbo-64 with a mark 1-2 command pod on top. Total mass on the pad is 46 tons. Mainsail has 1500kN thrust. Thats 32.6 meters/second^2 of acceleration and its thrust to weight ratio increases as it burns down the fuel. At burn out the same ship has 107 meters/second^2 of acceleration. Thats almost 11gs of force.

[AgentPaper]

Well, instead of that, I decided to play around with solar panels, robotic parts, and fairings:

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[Leon]

I did it, a Kerbal is in Space and Orbiting.

Salute Jedidiah Kerbal for his achievement. He will be remembered as the first Kerbalnaut from Upper Atmosphere Explorations to achieve an orbit.
Shame it is around the Sun.

[AgentPaper]

More fun with solar panels and cramped fairings:

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[Trekkin]

That is an intimidating capacity for solar power generation.

I assume the possibility of adding an equally formidible ion engine array has already occured to you?

[AgentPaper]

That is an intimidating capacity for solar power generation.

I assume the possibility of adding an equally formidible ion engine array has already occured to you?

Mostly I'm just trying to figure out how many panels I can fit into those fairings. I don't think I've hit the limit quite yet, heh.

As for ion engines, I don't have the patience for those. Not sure what I'd even want to do with them, anyways.

[Hawriel]

I am getting very skilled at smashing my vehicles into Mun. I am so skilled I find new ways, and added complications to do it.

I am glad to say my last lander can survived a very ruff landing that scattered parts all over the place. Jerwig will now have to hike it over to Jeb's Landing to meet Jebediah and Bill. Eventually I will land a habitat in the same quarter of of Mun they are standing in.

Note to all. Make sure your rovers are not top heavy and make them longer than a lander can is wide. Other wise it will roll over forwards on you. Also the rubber wheels are not suited to use on the Mun. However I did discover that they can be repaired by your Kerbenaut.

Now i just need to figure out how to attach a two seat rover underneath my hab module and not smash it on landing.

[Trekkin]

Can you use a skycrane type of arrangement, Hawriel? If your hab module can land on its own, it might be able to carry enough fuel to hover, drop the rover, move over, and then land.

[Artanis]

Before I bother trying to add mods to the game...do they work with the Steam version, or will Steam just re-d/l the whole thing and erase them? I'd like to get MechJeb (mostly just to save effort on relatively trivial calculations*), but if won't work out, I'd rather not waste the time and effort trying to get it to work.


Also, minor vent, feel free to ignore this bit:

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Grr, I decided to try to put a satellite in orbit around Duna, got it up into space, looked up a "when to send ships to other planets" calculator, aaaand...it turns out I have to wait a good quarter of a game year before I can send it. The soonest point I can send something to another planet is about three game weeks for Moho

*Like "how much delta-v is left in my tanks", for example.

[AgentPaper]

Before I bother trying to add mods to the game...do they work with the Steam version, or will Steam just re-d/l the whole thing and erase them? I'd like to get MechJeb (mostly just to save effort on relatively trivial calculations*), but if won't work out, I'd rather not waste the time and effort trying to get it to work.


Also, minor vent, feel free to ignore this bit:

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Grr, I decided to try to put a satellite in orbit around Duna, got it up into space, looked up a "when to send ships to other planets" calculator, aaaand...it turns out I have to wait a good quarter of a game year before I can send it. The soonest point I can send something to another planet is about three game weeks for Moho

*Like "how much delta-v is left in my tanks", for example.

I've been using the steam version with lots of mods, and it doesn't hamper it at all. If you try and overwrite the main files, that will get wiped out each time the game updates (but not between updates), but there aren't really any mods that do that.

[Pie Guy]

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Grr, I decided to try to put a satellite in orbit around Duna, got it up into space, looked up a "when to send ships to other planets" calculator, aaaand...it turns out I have to wait a good quarter of a game year before I can send it. The soonest point I can send something to another planet is about three game weeks for Moho

You know you can speed up time to like 50,000x when you're just on the launchpad before you do anything, right?

[Artanis]

You know you can speed up time to like 50,000x when you're just on the launchpad before you do anything, right?

I didn't know that I could do that on the launchpad

[Jimorian]

Another option for being able to do full warp from map mode is to put a satellite into Kerbin orbit at around 2 or 3 million meters (it doesn't have to be that high, but it makes it easier to pick it out from wider zooms). That way, if you have a ship in low orbit somewhere that doesn't allow full warp, you can click back to this in map mode, warp to your heart's content, then switch back.

[Impnemo]

Before I bother trying to add mods to the game...do they work with the Steam version, or will Steam just re-d/l the whole thing and erase them? I'd like to get MechJeb (mostly just to save effort on relatively trivial calculations*), but if won't work out, I'd rather not waste the time and effort trying to get it to work.


*Like "how much delta-v is left in my tanks", for example.

If thats really all you need, remaining delta-v in stage/total, twr, maximum/current thrust etc you can get all that with flight engineer.

[Hawriel]

Can you use a skycrane type of arrangement, Hawriel? If your hab module can land on its own, it might be able to carry enough fuel to hover, drop the rover, move over, and then land.

That's what I'm trying to pull off. I created a hab module by using two of the large passenger modules and making it so they would rest side ways on the heavy lander legs. There is a lot of room between the feet and the cylinder to play with. I will most likely have to add another fuel tank to the hab and more boosters for landing for the added weight of the rover.

My biggest and admittedly silliest problems come with how to construct the rover while sticking on the side of my hab in the assembly building. It gets kinda wonky in their with odd angles. The second is well is me not being nitpicky on how the rover looks. I want it simple but look more than steel plate, wheels, battery and drivers seat. I know silly. I'm getting hung up on how my hot wheels car looks instead of how it works.

I have made neat rovers on their own in the assembly building. Is there a way for me to import a saved craft while working on another one? That why I can just load the ship/hab, then load the rover attach and call it a day.

[Jimorian]

I've seen youtubers talk about a mod that let's you load in subsections of ships, so that you could say, have a rover module, then attach it to your standard lifter stage. I don't see this mod listed in the OP, though.

One thing you can do in vanilla, at least, is build your rover in the SPH to give you proper bilateral symmetry there with wheels and whatnot, save, copy that .craft file to your VAB folder, then load it in from there to build your lifter under it using proper rocket symmetry. If your command unit isn't pointed upward for launch, you can place a small dock in that direction so that you can choose "control from here" while on the launch pad to not have to translate directions in your head while reaching orbit and beyond.

In my own play I've built yet another new space station, and had lots more docking practice. Though it's funny, I've gotten so used to slugging around massive objects, that when I went to dock the "escape" pods on the docking tree pointing off the side, I had trouble with how twitchy they were even with fine controls on.

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I have an idea for a video let's play that I think will be pretty unique, but I'll need to install another hard drive to have room for the files.

[AgentPaper]

Those solar panels aren't very efficient. The ones in front are blocking the ones in back, so depending on the angle of the sun you're getting at most 33-50% of the energy you would get if they were all on the same plane.

[Jimorian]

True, but given how big it is now and with all the attached ASAS's, I've given up on station keeping, and this assures me that I will still get solar power even when the plane of the panels is straight on to the sun.