Orion aka "Ol' Boom-boom"

[nyrath]

My system is quite similar to yours, except I have 6 cores. and an NVIDIA GeForce GTX 570 (because I use Blender 3D, and it can utilize the GPU).

So I don't know what the problem is.

I've been working on implementing Anglave's suggestion of sucking the mass out of the magazines and injecting it into the engine. And making the magazines release upon command so Novasiliko can use it in his Orion. I'm working as fast as I can, but a bit more documentation on the API would help.

[NovaSilisko]

Don't rush it, rushing leads to mistakes and mistakes lead to frustration.

[nyrath]

Markarian421 and Anglave, when you get a chance please test the new version in the first post.

It is now in KSP 0.20 format, so please follow the directions to uninstall the old version first.

This implements Anglave's idea of removing the mass from the magazines and storing it in the engine. Warning: I have no idea if this fixes anything at all. All that I do know is that I can successfully fly into orbit and circularize the orbit while carrying a large load of magazines. But I usually can, when the same version fails on your systems.

I'm crossing my fingers.

[Anglave]

Downloading now. Will update this post with report.

Update: I'd like to report a success of the "no beans" mass-routing system!

No jitter on the pad and I expect orbit to be reasonably achievable.

I do wonder if the mass is "realistic" or not though. Maybe it's being multiplied somehow?

This craft:

uses the 400MN charges to ascend, and it's massive enough that the 3.5MN charges won't get it off the pad.

The RCS I installed, which was easily turning earlier versions, won't turn this craft perceptibly.

Second Update: The 400MN bomb magazines are REALLY heavy. You essentially need to use 400MN charges to lift them.

A more reasonable craft with two 80MN magazines, four 0.88MN magazines, and six standard 3.5MN magazines made a nice circular orbit. Though I don't see myself using the 0.88's. The 3.5's were quite small enough.

Third Update: Minor bug report, if I return to the space center and then resume my flight (or quickload), all magazines are feeding.

Edited June 6, 2013 by Anglave

[Moon Goddess]

Don't rush it, rushing leads to mistakes and mistakes lead to frustration.

Frustration leads to anger, anger leads to hate and hate leads to suffering. etc. etc.

[nyrath]

Downloading now. Will update this post with report.

Update: I'd like to report a success of the "no beans" mass-routing system!

No jitter on the pad and I expect orbit to be reasonably achievable.

Thank you so much! You solved the problem!

And I discovered that my ships no longer need launch struts. They will sit on the pad with no wobble at all.

I did have to fix it so that if a magazine was undocked or something, the mass was removed from the engine.

I do wonder if the mass is "realistic" or not though. Maybe it's being multiplied somehow?

This craft:

uses the 400MN charges to ascend, and it's massive enough that the 3.5MN charges won't get it off the pad.

The RCS I installed, which was easily turning earlier versions, won't turn this craft perceptibly.

Second Update: The 400MN bomb magazines are REALLY heavy. You essentially need to use 400MN charges to lift them.

A more reasonable craft with two 80MN magazines, four 0.88MN magazines, and six standard 3.5MN magazines made a nice circular orbit. Though I don't see myself using the 0.88's. The 3.5's were quite small enough.

I will confess that I interpolated the mass of the individual 80MN charges as I had no data. But the 400NM are as per the resource material.

However, I do not have a figure for the number of charges in a 400NM magazine. It could very well be less than 60.

I do agree that the 400NM magazines are ultraheavy. About 200 tons each.

I will add a debugging readout to make sure that the mass being added to the engine is not being multiplied or something like that. Did you ever get a ship with 400MN into space before, so you could test the RCS on it?

On my ships, I have three rings of 4 RCS, one ring at the edge between engine top and bottom of magazines, one at the bottom of the engine just before the shock absorbers, and one at the top of the support column.

The 0.88 were my invention, they were intended for Jebidiah, who wanted to land his ship under atom bomb power.

The 2NM were from the USAF Orion study, the 3.5NM are from the later NASA study. The NASA charges increase thrust at the expense of specific impulse, compared to the USAF charges.

Third Update: Minor bug report, if I return to the space center and then resume my flight, all magazines are feeding.

Yes, that is a known bug, it is in my Bugzilla list. The jumping magazines bug had priority.

Edited June 6, 2013 by nyrath

[Anglave]

Thank you so much! You solved the problem!

Glad I could be of some (however minor) value to the project. I think it's an awesome mod.

However, I do not have a figure for the number of charges in a 400NM magazine. It could very well be less than 60.

I think a magazine with 10 or 20 would be reasonable. Especially since we basically have to use pairs, though I guess given the way the jitterbug workaround is coded, pairs aren't strictly necessary.

20-40 charges for high thrust, then the more efficient / less massive charges for maneuver.

I will add a debugging readout to make sure that the mass being added to the engine is not being multiplied or something like that. Did you ever get a ship with 400MN into space before, so you could test the RCS on it?

I had not. I never had one last more than a few seconds. It's possible this is the intended mass. Since my above post I've managed to get a craft with two of the 400MN magazines into a circular LKO. Basically by turning toward the horizon with the RCS from the moment of launch. More control authority or less mass will be required. I'll add more RCS ports.

Edited June 7, 2013 by Anglave

[nyrath]

Glad I could be of some (albeit minor) value to the project. I think it's an awesome mod.

Thanks! But do not minimize your contribution. I was frankly pulling my hair out trying to fix this bug. Your solution was both elegant and was a shining example of thinking outside of the box. Literally.

If I had remembered more of my rocket science, I would have remembered how sensitive rockets are to being balanced. From my website I was focusing more on having the rocket balanced radially around the thrust axis. But here there was a problem with the rocket balanced between nose and tail. That's why the launch struts were formerly required to keep the rocket from jitterbugging on the launch pad.

But the main problem was that the KSP physics engine does not play well with objects of high mass and low volume, which could not be predicted.

[FireStormOOO]

And never mind that, missed the other 40 pages of thread... I'd be willing to help if it's needed.

[nyrath]

And never mind that, missed the other 40 pages of thread... I'd be willing to help if it's needed.

We are mostly in the testing stage. So you are welcome to download the mod, install it, and bang on it until it breaks.

Then tell us about the breakage (a recipe to recreate the bug would be super).

[Anglave]

A word of warning: Do not put anything besides magazines inside the magazine rack.

Incidentally, after the explosion, the jitterbug was back. Probably not really an issue.

My guess is the mass-moving wormhole code didn't load because it was interrupted by the craft's destruction.

Another note I think has been mentioned before, one can attach objects to the pusher plate. But they don't move with it.

On a brighter note, this works

radial attachment of parts to the outside of the magazine cradle is possible.

A final thought: Based on my few launches experience; from a gameplay perspective it would be nice to have an option between the 3.5MN and 80MN range.

3.5 won't lift the above pictured craft off the pad.

80 has nearly ten seconds between impulses, or you start to see this:

Edited June 7, 2013 by Anglave

[Splode]

Third Update: Minor bug report, if I return to the space center and then resume my flight (or quickload), all magazines are feeding.

This is a bug with ksp, not the mod. Drives me crazy when I use all my lander rcs during interplanetary manoeuvres.

[Markarian421]

I'm still getting frequent explosions on the pad, but I suspect this has to do with how massive the magazines are and (thus) the ineffectiveness of the 3.5MN's to lift the thing off the ground. I can get in the air with the 80MNs, but if I try to use the 3.5's in the small magazines, I think what's happening is that the launch towers are instantly destroyed and I drop to the ground, and the instant I hit the ground all the magazines violently eject/explode.

[Markarian421]

A word of warning: Do not put anything besides magazines inside the magazine rack.

From what I'm seeing, don't put anything on top of the magazine rack either. I can't tell if the stuff I mount on top is exploding because the magazines are hitting them or for some other reason, but whatever I have attached up there is being destroyed.

[Markarian421]

And in case is sounds like I'm not having any fun with this (nothing could be further from the truth) -- last night using the engine w/o the rack, plus the 3.5x600 rack plus a single magazine of 80's I took off from the pad and intercepted Jool (mostly by luck) and aerobraked into a orbit between Lathe and Tylo. I brought along all that extra fuel and all those extra engines, and barely needed them . . .

Edited June 7, 2013 by Markarian421

[NovaSilisko]

I'm running into an issue. It seems like my ship weighs far far more than the parts would suggest.

Now, 65 bombs per container, 0.3 mass per bomb = 19.5 mass. 6 bomb containers = 117 mass. 6 docking ports for the containers = 3.9 mass. The cabin, 23.6 mass, and the pusher plate 25. 117 + 3.9 + 23.6 + 25 = 169.5 tons.

Except, it weighs a LOT more than that...

So, something weird is going on...

Edit: Forgot bomb canister dry mass, but that only comes out to 4.8 tons so not enough to cause this.

Edited June 7, 2013 by NovaSilisko

[Canopus]

The newest update solved my problem, thanks nyrath

Edit: i just noticed how massive the parts now are. Very hard to control.

Edited June 7, 2013 by Canopus

[NovaSilisko]

Maybe check and see if the mass adds up properly from the listed values in the VAB? The stock parts might be suffering from the same issue as mine...

[nyrath]

Well, it's pretty clear from all of your reports that I've created a bug in the mass-transference code. Not surprising, it is a little involved. I have to initialize it by pre-loading each magazine's mass (less one ton) into the engine's mass. Then when the magazine burns a bomb, it recalculates its mass, I subtract its old mass from the engine and add in the new recalculated mass. Obviously I made a mistake somewhere.

I'll put in lots of debug log statements and try to track this down. And try to not fret that by fixing this bug I might bring back the dancing magazine problem...

My only other worry is that I might have made another problem. In prior versions, there did not seem to be any problems with fancy payloads placed on the top of the engine column. Please be on the look out for such problems.

I also have the odd feeling that the engine missing the center column is more stable than the one with the column. You might want to experiment with that engine, foregoing the magazine rack and making your own center column out of struts and stuff.

[Canopus]

The Engine with the column works very good for me, even with heavy payloads under strong acceleration.

[kahlzun]

Am I the first person to try turning this into a horizontal vehicle since its release?

[nyrath]

The Engine with the column works very good for me, even with heavy payloads under strong acceleration.

Holy Oberth Effect! That's a big spacecraft stack! But I'm glad the central column isn't doing anything weird.

Am I the first person to try turning this into a horizontal vehicle since its release?]

Great Tsiolkovsky's Ghost! Yes, kahlzun, you are the first. That's almost as terrifying as the seven Orion array I saw.

[Canopus]

Holy Oberth Effect! Great Tsiolkovsky's Ghost!

Those are just great

[Anglave]

I have to initialize it by pre-loading each magazine's mass (less one ton) into the engine's mass. Then when the magazine burns a bomb, it recalculates its mass, I subtract its old mass from the engine and add in the new recalculated mass. Obviously I made a mistake somewhere.

In the above system as you stated it, the magazine's mass is being recalculated after every bomb. And the new mass is being added to the engine. (and the old mass deducted). Thus decreasing the engine's mass by the mass of the expended bomb, as intended.

Since you're adding the mass of the magazine to the engine, please do subtract it from the magazine

Better yet, calculate what the magazine's mass would be and add that to the engine, without ever changing the magazine's actual mass. (perhaps this is what you're actually doing).

I'm not sure if it's more efficient to keep an "oldMass" for each magazine and do your "subtract old mass, add new mass" dance, or simply sum the current mass of all magazines (less one ton each) and shunt that to the engine every cycle (so engine's mass is always it's dry mass + shunted mass). Though the second approach seems more straightforward to me; fewer variables and no need to track which magazine did what. Just sum them all every time a charge is expended. Probably more math, but probably not a meaningful change in cpu load.

And a lot less chance for things to go screwy. After every impulse, the engine's mass gets set to it's dry mass + the mass that should have been in the magazines. The magazine mass never changes.

Possibly better yet (though it may not allow for ejecting magazines or replacing them in flight or other strange behavior) but you could just Initialize by calculating the appropriate mass of all magazines and adding that to the engine, then when a bomb is expended simply deduct the mass of that bomb from the engine. (you'd need to know what size bomb) Rather than recalculating magazine mass at all. (The magazines just always have their low constant mass). This potentially saves a lot of clock cycles, but adds places where the code could break down.

... try to not fret that by fixing this bug I might bring back the dancing magazine problem...

I highly doubt that it would. Edited June 7, 2013 by Anglave

[Anglave]

The Engine with the column works very good for me, even with heavy payloads under strong acceleration.

I'd like to second this. I'm not having stability or spontaneous explosion issues. It's working great. Except that the 3.5MN charges and my RCS are a bit anemic compared to the mass of the craft.

Edited June 7, 2013 by Anglave