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[1.8-1.11] Advanced Jet Engine v2.17.0 (June 26)


blowfish

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  • 1 month later...

Hi

I noticed that helicopter tail rotors does not seem to produce counter thrust. I am using Airplane Plus and its config from here

I am positively sure that the config format is correct. Please advise. Thank you.

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18 hours ago, camlost2 said:

@damowang2

1. The helicopter config for APP is included in AJE not AJEextended.

2. Did you set the PID parameters for tail rotors?

 

It indeed outputs thrust when I add steering response and pid parameters, but it does not seem to automatically counter the torque of main rotor. Does mod author keep a documentation about how these PID factors works? 

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1 hour ago, damowang2 said:

It indeed outputs thrust when I add steering response and pid parameters, but it does not seem to automatically counter the torque of main rotor. Does mod author keep a documentation about how these PID factors works? 

if it doesn't counter torque what does it do?

What you are looking for is actually a PID-tuning method right? There're several general methods but none specific to this mod.

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22 hours ago, camlost2 said:

if it doesn't counter torque what does it do?

What you are looking for is actually a PID-tuning method right? There're several general methods but none specific to this mod.

The testing helicopter I built is gently turning in the opposite direction of rotor spinning, as if the torque is not completely accounted for and dampened by the rotor, and I have to apply manual rudder input to stop the spin. Then the rotor produced rolling torque because it is not built in line with CoM, and I seems to have to control that by applying manual collective input.

I somehow understand that PID control is based on relationship between desired value and actual value, but I don't know what the desired value is in this context, and I may need documentation about that. Reading source code for this make it look more like a job and not recreational thinking.

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On 8/5/2018 at 9:20 AM, damowang2 said:

The testing helicopter I built is gently turning in the opposite direction of rotor spinning, as if the torque is not completely accounted for and dampened by the rotor, and I have to apply manual rudder input to stop the spin. Then the rotor produced rolling torque because it is not built in line with CoM, and I seems to have to control that by applying manual collective input.

I somehow understand that PID control is based on relationship between desired value and actual value, but I don't know what the desired value is in this context, and I may need documentation about that. Reading source code for this make it look more like a job and not recreational thinking.

If you have experience in flight simulators you can see that is how a helicopter flies. Congratulations

Desired value is rudder input, but some input left and right is always needed. Limitation of PID controllers

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  • 2 weeks later...
32 minutes ago, Sebastiaz said:

Hey, funny question to ask, my bad if it has been asked before, but is there anyway to change an engine cfg made for AJE back to a normal stock cfg? Just wondering, attempted to so but to no avail.

Remove the AJE patch that modifies it?

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19 hours ago, Sebastiaz said:

The modified cfg already comes with the engine mod, there's no separate download for a stock cfg.

Oh, that's probably somewhat more difficult.  You'd have to write a patch that replaces the AJE engine module with a normal one.  It might be missing some parameters that are necessary though, hard to say.

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59 minutes ago, blowfish said:

Oh, that's probably somewhat more difficult.  You'd have to write a patch that replaces the AJE engine module with a normal one.  It might be missing some parameters that are necessary though, hard to say.

Ah ok, I've been trying myself, and all I've gotten is the kraken when I replace some of the .cfg with a stock .cfg (Unable to move camera, zoomed out, going 0000000m/s, y'know) 

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1 hour ago, Sebastiaz said:

Ah ok, I've been trying myself, and all I've gotten is the kraken when I replace some of the .cfg with a stock .cfg (Unable to move camera, zoomed out, going 0000000m/s, y'know) 

It's not quite that simple. You need to know the name of the objects in the model used for thrust transforms and any animations and the like. You should be able to get that from the AJE config and adapt an existing stock config with them, but dropping in a stock config is going to have it trying to apply things to objects that don't exist.

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2 hours ago, blowfish said:

Yeah unfortunately there's no generalized way to convert between AJE and stock engine modules.  It really depends on the exact part and how it's configured.

Ah okay, just wondering, the mod in specific is the "Real Engines" mod, the one that comes with props, etc. Was gonna give that whirl, hopefully there's a way to do so, I've managed so far to get the engine tab on the bottom left side to pop up, but if i try to add a replacement .cfg too the thrust etc, the Kraken likes to appear. @Citizen247 Their animations are based on Firespitter too , so it makes it slightly easier, other than that, I'm not sure what else to do.

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On 8/28/2018 at 7:39 PM, Sebastiaz said:

@Citizen247 Their animations are based on Firespitter too , so it makes it slightly easier, other than that, I'm not sure what else to do.

1

The animations will be linked to objects in the .mu, so you generally need to know what the object names are. There's also thrust transforms that tell the game how to apply the engine thrust to the part. If the names are wrong the game will try to apply thrust by a transform that doesn't exist, which I imagine would likely cause some tentaclely-ness to emerge. I thought "real engines" was just rockets? If you have a link to the mod in question I can try and take a quick to see if I can get a working config out of it?
 


I've been thinking about a mod for some time, not sure my coding skills are entirely up to it, but it doesn't stop me thinking about it... anyway I was wondering if AJE could function as a back-end to it:
Basically a modular engine mod, so rather than having the propellor defined as part of the engine, for instance, they're separate parts. The engine provides power to propeller part which won't work without it, and the propeller produces thrust based on how much power is provided by the engine. The engines could also be hooked up to generators or wheels also though. So a bit like how Interstellar lets you hook reactors up to other different parts to produce different configurations. Similarly, with Turbines, plug a jet nozzle on it, it'll function as a basic Turbojet but you could also add an afterburning jet nozzle. Or perhaps a ducted fan to create a Turbofan or a prop for a turboprop. The mod would need to provide a ui to tune the powerplant to it's usage, perhaps even a career mode where engines are developed based on tech level, i.e. number of pistons and the power of each piston selectable based on tech level and that affects how much the engine costs and so on.

Of course the more I think about it, the more complex and unattainable it seems, but I was wondering if something along those lines could be created, and use that to produce configs for AJE to simulate in flight? I mean a cut down version of that might be to be able to adjust AJE configs in some way in game. Like change propellors, add or remove afterburners, have some facility to improve some engine characteristics to produce different marks of engine without spamming hundreds of parts in the editor. It's sort of why I started working on AJE-Extended, because no matter how many engines I have, I always find I need another one...

Edited by Citizen247
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Sorry for the late reply, the mod is slightly defunct, but it's still compatible with 1.3.1 with AJE, here's the link to the download:
https://github.com/gertsonderby/RealPlanes

Sorry, Realplanes, same thing though really, they add real engines, to download it, just click "Clone or download", and open the package folder, drag VTProp in and you're good to go.

 

Edited by Sebastiaz
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  • 2 weeks later...

Hi everyone!

I just discovered something I would like to ask about.

I appreciate @blowfish taking my data into account and taking the steps to adjust the calculated idle thrust of the engines, but I am afraid it, somehow, did not have a significant effect.

The numbers above suggest, that static idle thrust should be, from 3-4% of the full rated thrust, for high bypass turbofans, to 7-10% for turbojets without bypass. Currently the stock TF-34 turbofan, for example, develops as much as 7 kilonewtons of idle thrust, which is 17% of its rated 41kN. This appears to be almost the same as before, if I recall the previous test runs correctly. The CF-6 produces over 18 kilonewtons which is almost twice as much as it should do. The CF-6 variants are actually among the engine types that are shown in the Boeing documents. See the first of my three links on page 12.

Also KSC seems to be an extremely hot place. As hot as 40 degrees C. That means that engines, of course, do not develop their full thrust, so on standard day, idle thrust is higher than that.

I understand that this discussion is a bit dated, but I took a break from kerbal things for a while and just recently came back to building kerbal planes seriously.

Maybe there is something overriding the default idle exit pressure value in the engine specific configs? Or some other setting affecting this? Also as most of jet engine nozzles are subsonic, should the pressure at the outlet actually be less than ambient and not more?

Thank you!

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I'll take another look, there may still be room to tune the parameters.  One other thing is that the nozzle exit area is probably set for cruise conditions in real life, whereas in AJE it's fudged somewhat - what this means is that at idle AJE engines may be producing more thrust than they should due to the nozzle being closer to the ideal shape for that exit pressure.  This would not be a trivial problem to solve unfortunately, but I can look into it.

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7 hours ago, Ninadragonborn said:

can i play this in 1.4.4 or not does it work in this version ?

Dude, it takes 5 min too find that out for yourself but yea it works fine on 1.4.5 here. Im basicaly running the entire Realism Overhaul suite on 1.4.5 :cool:

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On 9/24/2018 at 11:38 PM, Cratzz said:

Dude, it takes 5 min too find that out for yourself but yea it works fine on 1.4.5 here. Im basicaly running the entire Realism Overhaul suite on 1.4.5 :cool:

thanks a lot :D

but the problem is 

i can get the

FAR 

working 

i am playing in RSS 

i have done all in the 

FAR page 

add the version that was posted that works on 1.4 

but its not working 

so i can't use this 

 

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