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[1.3.0] Kerbal Engineer Redux 1.1.3.0 (2017-05-28)


cybutek

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Hey all,
Hoping someone who has had a similar problem can point me in the right direction here.
My Kerbal Engineer has started causing a problem for me all of a sudden.

Running the latest version on a heavily modded 1.1.3 KSP install.
it has been working just fine until recently.

Now the stats I am getting in the VAB are not the same as when I launch.
I'd build a rocket, and the 1st stage would have an TWR of about 1.25 or so. (low and a slow lift off but workable)
But when I go to launch that very same rocket, on ignition of the 1st stage I am getting a TWR of 0.33 and just sitting on the pad burning fuel until the loss of fuel weight brings the TWR up to greater than 1.
Anyone else having trouble with Engineer giving you bogus stats in the VAB?


I have a hunch it has something to do with M.O.L.E. Parts as it seems to happen when I have tanks and Decouplers from that Mod in the rocket.

Anyone else have experience working with Engineer with M.O.L.E.?
Engineer is not reading those parts correctly?
 

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29 minutes ago, CG-23 Sailor said:

I'd build a rocket, and the 1st stage would have an TWR of about 1.25 or so. (low and a slow lift off but workable)
But when I go to launch that very same rocket, on ignition of the 1st stage I am getting a TWR of 0.33 and just sitting on the pad burning fuel until the loss of fuel weight brings the TWR up to greater than 1.
Anyone else having trouble with Engineer giving you bogus stats in the VAB?

Double check that you are looking at atmospheric stats in the VAB rather than vacuum, some engines perform very poorly in atmo and produce far less thrust.

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1 hour ago, CG-23 Sailor said:

Anyone else having trouble with Engineer giving you bogus stats in the VAB?

I've noticed the DeltaV numbers seem to be quite a bit off at times, but I haven't looked at the TWR that closely.  I'm pretty sure I'm looking at the atmospheric numbers in the VAB, too, but once I get it on the pad, I'm seeing 500-1000 m/s less.

I do have MOLE installed, but I'm seeing this on vehicles without any of the parts installed.

Edited by razark
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21 minutes ago, Red Iron Crown said:

Double check that you are looking at atmospheric stats in the VAB rather than vacuum, some engines perform very poorly in atmo and produce far less thrust.

Yes. I am aware of Atmospheric vs Vacuum stats.

It is showing the Atmospheric stats. 
The stats however change from what is shown in the VAB vs an actual launch.
And not slightly either, but by an amount that makes the Engineer in the VAB totally useless.
Craft that should have no trouble completing the designed mission according to the VAB stats, cannot even get off the pad.

 

Edited by CG-23 Sailor
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3 minutes ago, CG-23 Sailor said:

Yes. I am aware of Atmospheric vs Vacuum stats.

Apologies, just checking the simplest things first. (I still catch myself making that mistake after years of using KER.)

3 minutes ago, CG-23 Sailor said:

It is showing the Atmospheric stats. 
The stats however change from what is shown in the VAB vs an actual launch.
And not slightly either, but by an amount that makes the Engineer in the VAB totally useless.
Craft that should have no trouble completely the designed mission, cannot even get off the pad.
 

Are you using any mods that change the fuel resources? I've had some similar problems with RealFuels.

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24 minutes ago, Red Iron Crown said:

Apologies, just checking the simplest things first. (I still catch myself making that mistake after years of using KER.)

Are you using any mods that change the fuel resources? I've had some similar problems with RealFuels.

Nope, only visual mods in regards to engines, like real plume, but not real fuels.

IN fact, the specific rocket in question had a stock engines on the first stage with Titan tanks from the MOLE mod, and engines from Contares in the upper stage. But all of the stats should be baseline without any alteration from other Mods like Real Fuels etc..
 

Edited by CG-23 Sailor
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  • 2 weeks later...

I just found a small bug in KER. In GameData\KerbalEngineer\Parts\EngineerChip there are two part cfgs that define the part, part.cfg and EngineerChip.cfg

This doesn't seem to cause any problems in and of itself, but it's giving my contract pack the fits because there are two defined parts with the same name.

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1 hour ago, 5thHorseman said:

I just found a small bug in KER. In GameData\KerbalEngineer\Parts\EngineerChip there are two part cfgs that define the part, part.cfg and EngineerChip.cfg

This doesn't seem to cause any problems in and of itself, but it's giving my contract pack the fits because there are two defined parts with the same name.

There is no part.cfg in that folder in the download.  I suspect this was left over from a previous version, in 1.0.19.4 and earlier it was called part.cfg.

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Just now, Padishar said:

There is no part.cfg in that folder in the download.  I suspect this was left over from a previous version, in 1.0.19.4 and earlier it was called part.cfg.

Hm, I may have left it as detritus when upgrading. I usually delete the directory first but must have forgotten this time.

I apologize.

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Feature request: KER for docking! roll, pitch, yaw, x,y,z relative speeds and x,y,z displacements with autohiding feature (only shown when the target is set, similar to relative speed right now).

Basically i want to setup a panel which will appear when i set the target, it should display all the stats needed for docking and will dissapear automatically when i finish the dock (because there is no target set anymore). Also... the stats should be visible only if you are in physics range (you don't want to see that before intercept).

Roll stat isn't nesessary for docking two ships, but is sure usefull when you are building the station and want to attach that node at the 90 degree angles exactly.

Thanks, and i hope to see it soon.

Edited by Myslius
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@cybutek

Bug report. Craft:

https://kerbalx.com/sharpy/Plugs

Two stages, pure MK1, Vector engine on bottom stage, Terrier on upper.

The craft normally reaches orbit with good 2000m/s of dV to spare.

KER goes completely bonkers about its parameters in VAB.

G3ls3ab.png

When I enable crossfeed, or disable staging of second stage, then it starts recognizing it, pulling some other stupud numbers out of a hat. (I assure you stage 1 nearly reaches orbit, so it has way more than 208m/s...)

GFBl6Iy.png

The reason is probably ludicrously high TWR.

Edited by Sharpy
kraken ate a screenshot
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19 minutes ago, Sharpy said:

The reason is probably ludicrously high TWR.

The reason is more likely to be something simple like the root part of the vessel being in the part that gets decoupled. KER may not support enabling of crossfeed on decouplers properly but it should cope fine with a simple 2 stage rocket. 

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22 minutes ago, Sharpy said:

@Padishar Yes, the root part is in the discarded launch stage - still, the calculations are entirely bogus.

Try rerooting it to a part in the payload. KER can't predict what is payload and what is discardable junk other than by root part, so it is assuming the rocket will stage away all the other stuff earlier than you're planning.

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41 minutes ago, Sharpy said:

@Padishar Yes, the root part is in the discarded launch stage - still, the calculations are entirely bogus.

No, they really aren't, you just have to accept that KER only calculates the deltaV that each stage applies to the root part.  If you decouple the root part from the remaining engines then all the following stages calculate as 0 (stage 0 in your first screenshot, click the All Stages button to see stages that don't generate any deltaV).  The value for stage 1 in the first screenshot is almost certainly correct.  If you change the root part to one that stays with the vessel (e.g. the command pod or probe core) then stage 0 should also show up.

In any case, with KSP 1.2 being just around the corner and making significant changes to how fuel flow works, very little work is likely to be done on fixing issues with the existing deltaV calculation code because a significant amount of it is likely to be rewritten.

Edit: incidentally, the reason for the odd looking numbers when you enable crossfeed is that initially the vector draws the fuel across the decoupler from the payload but it only has enough for 6s of burn.  After this, the parts that get decoupled from the root no longer contain any fuel so they are treated as dead weight and the simulation stages to eject them.  The stage 0 numbers are the Vector engine burning the fuel in stage 1 and it gives more deltaV because the top of the rocket is no longer attached.

Edited by Padishar
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23 minutes ago, Padishar said:

No, they really aren't, you just have to accept that KER only calculates the deltaV that each stage applies to the root part.  If you decouple the root part from the remaining engines then all the following stages calculate as 0

Then that rocket is damn efficient to reach the orbit on 2800m/s. :D

Edited by Sharpy
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35 minutes ago, Padishar said:

The root part doesn't reach orbit...

One time I managed to close the orbit, with PE of 3 kilometers :)  How much delta-V did I miss?

But as I think of it - it IS possible. I need 2400m/s of horizontal speed, and I reach space really, really fast, so my gravity losses are quite minor.

Edited by Sharpy
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3 hours ago, Jarin said:

Looks like vessel DeltaV readouts are not aware that Rapiers draw from the entire craft, even in closed-cycle mode. 

Evidence?  E.g. screenshots, craft file, detailed description of exactly what you think is wrong, etc...

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Okay, pretty straightforward test. Let's take my new crew transport. That file has fuel lines on it, making all fuel reach the rapiers by standard fuel flow rules.

- First launch, hit 2 to toggle to closed-cycle, Note the delta-V readout in KER, then start burning fuel. Easiest to just point it straight up and let it run out of ox. Note the way the fuel drains evenly across the craft, all tanks draining at the same rate, just like a jet in airbreathing mode.

- Now revert to the VAB, pull off the fuel lines. They're all visible from below; only one slightly hidden is right at the split between Mk2 fuselages on the wing.

- Toggle to closed-cycle and make note of the delta-V readout again. Note how it's significantly lower (it's not realizing that the main body's fuel will reach the engines). Take off and note how it drains fuel the same way as before, getting just as far before the ox burns out, despite showing less than half the dV in KER.

 

Basically, rapiers in closed cycle mode use STAGE_PRI (ALL_VESSEL, but sorted by stage) fuel flow rules, just like in airbreathing mode. KER appears to be calculating as if closed-cycle uses normal flow (STACK_PRIORITY_SEARCH, I think?), or at least respecting crossflow rules of that mode for radial attachment, where STAGE_PRI does not.

Edited by Jarin
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