Horizon Aeronautics - Development Thread

[MOARdV]

Checking stage only still yields the same results - My tanks have fuel but the staging area icon runs out (and I get engine burn-out) before they are even empty.

What are the fuel tank capacities for Kerosene & LOX in the fuel tank config? And what are the ratios for the propellants in the engine's config?

[stubbles]

Tank cfg snippet

RESOURCE
{
	name = Kerosene
	amount = 1500
	maxAmount = 1500
}

RESOURCE
{
	name = LOX
	amount = 1800
	maxAmount = 1800
}

Engine cfg snippet

MODULE
{
	name = ModuleEngines
	thrustVectorTransformName = thrustTransform
	exhaustDamage = True
	ignitionThreshold = 0.1
	minThrust = 0
	maxThrust = 1700
	heatProduction = 450
	fxOffset = 0, 0, 0.5
	PROPELLANT
	{
		name = Kerosene
        	ratio = 0.9
		DrawGauge = True
	}
	PROPELLANT
	{
		name = LOX
		ratio = 1.1
	}
	atmosphereCurve
 	{
	 key = 0 337
	 key = 1 309
 	}
}

[MOARdV]

(snip snippets)

It's an imbalance between fuel consumption and fuel supply. To balance the LOX, multiply the Kerosene value by (1.1 / 0.9). In this case, that's 1833.3333333.

To get a nice, even number, the Kerosene value should be a multiple of 9. The easy way to get that: make sure the digits of the Kerosene value adds up to 9. For instance, change Kerosene to 1503, and LOX to 1837.

[stubbles]

I'll give that a shot, thanks Moar. Is there some guidelines you know of for some of this kind of stuff? It's not in the main compilation thread. I'm just an artist, so tracking down this math crap hurts

[MOARdV]

I'll give that a shot, thanks Moar. Is there some guidelines you know of for some of this kind of stuff? It's not in the main compilation thread. I'm just an artist, so tracking down this math crap hurts

Hey, easier than a math guy like me trying to do art. "Engineer art" is the punchline to jokes for a reason.

The guideline in this specific case is that the "ratio=" numbers in the engine PROPELLANT fields tell you the relative rate of consumption on those two fuels. If you changed them both to 1.0 (instead of 0.9 and 1.1), then you could use the same fuel amounts for both fuel types. I haven't seen anyone do that, though I'm sure there are some realism aficionados who would be happy to give you other ratios to use.

[Guest]

I'll give that a shot, thanks Moar. Is there some guidelines you know of for some of this kind of stuff? It's not in the main compilation thread. I'm just an artist, so tracking down this math crap hurts

Want some config help? I'm pretty skilled with that. Those thing are not hard, but if you're having trouble with them, I can try to help out.

Also, did you model the RD-8 verniers for the Zenit's second stage? Those are small, gimballed steering engines used for 2nd stage attitude control. The main engine isn't gimballed.

Edited February 1, 2014 by Guest

[stubbles]

I'm still having issues with those settings. It's much better, but I'm still hitting burn-out before either tank is actually dry. I'm using a custom resource - does that matter? It's basically the same as the default fuel, I just named it differently - still us 0.005 for the fuel density.

Dragon - if you could look these over, sure. Though I don't really want to be passing out the assets yet as they're nowhere near done.

RD-58M Engine w/integrated tank

This one burns out with around 15% fuel still in both tanks

PART
{
// --- general parameters ---
name = HA3SLRD58M
module = LiquidEngine
author = stubbles

// --- asset parameters ---
mesh = model.mu

// --- node definitions ---
node_stack_bottom = 0.0, -1.315, 0.0, 0.0, 1.0, 0.0
node_stack_bottom003 = 0.0, 1.336, 0.0, 0.0, 1.0, 0.0
node_stack_center = 0.0, -0.315, 0.0, 0.0, 1.0, 0.0
node_stack_left = -1.25, 1.5116, 0.0, 0.0, 1.0, 0.0
node_stack_right = 1.25, 1.5116, 0.0, 0.0, 1.0, 0.0
node_stack_top = 0.0, 1.692, 0.0, 0.0, 1.0, 0.0

// --- FX definitions ---
fx_exhaustFlame_blue_small = 0.0, -3, 0.0, 0.0, 1.0, 0.0, running
fx_exhaustLight_blue = 0.0, -2.3, 0.0, 0.0, 0.0, 1.0, running
fx_gasJet_white = 0.0, -2.3, 0.0, 0.0, 0.0, 1.0, running
fx_exhaustSparks_flameout  = 0.0, -3, 0.0, 0.0, 1.0, 0.0, flameout

// --- Sound FX definition ---
// sound_vent_medium = engage
// sound_rocket_hard = running
// sound_vent_soft = flameout

// --- editor parameters ---
cost = 950
category = Propulsion
subcategory = 0
title = (3SL) RD-58M
manufacturer = Horizon Aeronautics
description = 

// attachment rules: stack, srfAttach, allowStack, allowSrfAttach, allowCollision
attachRules = 1,0,1,1,1
stackSymmetry = 1
// --- standard part parameters ---
mass = 1.5
dragModelType = default
maximum_drag = 0.2
minimum_drag = 0.2
angularDrag = 2
crashTolerance = 7
breakingForce = 300
breakingTorque = 800
maxTemp = 2500
stagingIcon = LIQUID_ENGINE

MODULE
{
	name = ModuleEngines
	thrustVectorTransformName = thrustTransform
	exhaustDamage = True
	ignitionThreshold = 0.1
	minThrust = 0
	maxThrust = 200
	heatProduction = 300
	fxOffset = 0, 0, 0.2
	PROPELLANT
	{
		name = Kerosene
        	ratio = 0.9
		DrawGauge = True
	}
	PROPELLANT
	{
		name = LOX
		ratio = 1.2
	}
	atmosphereCurve
 	{
   	 key = 0 352
  	 key = 1 300
 	}
}

RESOURCE
{
 name = Kerosene
 amount = 150
 maxAmount = 150
}

RESOURCE
{
 name = LOX
 amount = 200
 maxAmount = 200
}

MODULE
{
	name = ModuleAnimateHeat
	ThermalAnim = EmissiveAnimation
}

MODULE
{
	name = ModuleAlternator	
	RESOURCE
	{
		name = ElectricCharge
		rate = 2.0
	}
}

}

[NoMrBond]

Your draw amounts (0.9/1.2) add up to 2.1, so the proportions are actually going work out around ~42.86% Kerosene and ~57.14% LOX instead of the 45%/55% you seem to be expecting with your 150/200 fuel amounts

[Edit] Try Kerosene/LOX ratio's of 0.8 and 1.2 and amounts of 144 and 216 respectively

Edited February 2, 2014 by NoMrBond
accidentally maths

[stubbles]

Your draw amounts (0.9/1.2) add up to 2.1, so the proportions are actually going work out around ~42.86% Kerosene and ~57.14% LOX instead of the 45%/55% you seem to be expecting with your 150/200 fuel amounts

[Edit] Try ratio's of 0.8, 1.2 respectively and Kerosene/LOX amounts of 144 and 192 respectively

Oiy. So what's the ratio math I need to use then to nail it every time? I did what Moar suggested, in order to get those values. I can't find any solid info on this stuff.

[NoMrBond]

Make sure your ratio numbers add up to 2

Pick/set a number of 'units' (I picked 180 above) and multiply by your ratio's

180 * 0.8 = 144 Kerosene

180 * 1.2 = 216 LOX

[stubbles]

Wait, so what does the 180 "units" come from? Units of what?

The values worked perfectly btw, thanks!

Edited February 2, 2014 by stubbles

[NoMrBond]

You have to pick the numbers from somewhere (where did the 150 kerosene in your RD-58M come from for example), either tank volumes or liters of fuel (if a KSP fuel unit is even a liter), iterating up/down until it burns long enough for what you're making, or you can work out exact amounts using engine ISP etc

I guessed ~180 because 180 * 0.8 came out approximately around the original 150 you'd listed and 180 * 1.2 was also a whole number (instead of something.4 etc), two simple multiplications just seemed easier

Direct would be (150/0.8) * 1.2 = 225 [150 Kerosene with 225 LOX assuming ratio's of 0.8 and 1.2 respectively]

[stubbles]

Ah okay, so the value was derived from the fuel quantity I desire - makes sense now Was wondering where the heck these things were coming from. I need to tweak things a bit, bit it's definitely working better now. Thanks so much, guys!

[Guest]

Yeah, pretty much this. Also, unless you actually need different densities, go with stock fuels. That'll make sure the mod doesn't conflict with others, such as RealFuels.

[stubbles]

Been messing around with HotRockets FX stuff. ;D

Got the fuel issues all sorted, but I'm dealing with other problems now. Never ends! hah.

[likke_A_boss]

Wow, very nice FX! I wish all modders put in HotRockets FXs...

[aeTIos]

I know that asking for ETA is a no-no, but I'm too lazy to read all 15 pages of this thread. Is there a dl link for this already? I love how it looks!

Also, I agree with Dragon01 that you should probably use LF/OX on your tanks so that it doesn't conflict. You can still use different ratios if you want.

[stubbles]

Is there a dl link for this already? I love how it looks!

Thanks! Still working on it right now though. Texturing isn't done and I'm still sorting out config issues. I'd guess another month or two until release.

I swapped back the tanks to use LF/OX already, so that should help.

[Proot]

Ey! Amazing work!!, and great tips and visual lessons about texturing! haha I learn very quick so thank you!

[Kerbal01]

amazing!

(10char)

[SkyHook]

This is going to be creepy but once a week or so I see the word "Horizon" and click on the forum thread, thinking it it is this forum. I am quickly disappointed when it is not the rocket pack that I was thinking of. Today is the day that I am not disappointed! Stubble will find that the state of rocket FX has improved, and that texture management is easier than ever. This will make for a better finished product.

[stubbles]

Here's two WIP shots of the RD-171 main engines. The diffuse is about 70% done, but I haven't really done anything to the spec yet, so it's a bit glossier than it will be in the end.

[BLUAV8R]

Woah! Love the textures! MORE!

[OopsThatNotWork]

Woah! Love the textures! MORE!

I second this motion!

[stubbles]

Thanks guys! Glad you're liking it so far. finished up the engine finally, here's some shots:

Edited February 10, 2014 by stubbles