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Space Shuttle - Development

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Re: Space Shuttle - Development

Postby Thorsten » Wed Nov 13, 2019 6:17 pm

Going back to 2018.3, I've tested entry and landing, RTLS and TI targeting today (the new scenario function is really good to quickly get into the action...) and all worked flawlessly.

I'm going to test some capture and proximity stuff tomorrow, perhaps also another TAL, but I believe the new milestone is around the corner.

(Actually, having not flown an RTLS for a while, I kind of admired the good judgement the DAP displayed - I was high on energy at TAEM interface and immediately the logic decided to fly S-turns which worked perfectly to dissipate the excess energy, bringing me right into a standard approach.)
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Re: Space Shuttle - Development

Postby GinGin » Wed Nov 13, 2019 7:48 pm

Perfect.
I Played a lot with 2018.3, rock solid
Indeed for the RTLS, DAP is doing a great job until CSS.
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Re: Space Shuttle - Development

Postby Thorsten » Thu Nov 14, 2019 2:07 pm

Okay, milestone 12 is tagged after a flawless satellite capture test - which means... we're up for more risky development again.
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Re: Space Shuttle - Development

Postby Thorsten » Thu Nov 14, 2019 4:16 pm

And here's some impressions from testing

Fuel dump during an RTLS:

Image

ET separation and pitchup before Nz-holding phase:

Image

Alpha transition (in the event, I was high on energy so I got to experience S-turns later):

Image

Night portion of the orbit, after TI burn in transit to ISS:

Image

ISS in view:

Image

Approaching a satellite for capture:

Image

Stationkeeping in capture position:

Image

And... grabbed in the first attempt:

Image

View from the payload specialist station:

Image

Off into the sunset :D

Image
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Re: Space Shuttle - Development

Postby GinGin » Thu Nov 14, 2019 4:34 pm

Very nice Thorsten .
Need to get into that satellite recapture .
Is there a specific point to aim with the rms ?

When I look through the differents milestones, I am impressed by the evolution .
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Re: Space Shuttle - Development

Postby Thorsten » Thu Nov 14, 2019 4:48 pm

Is there a specific point to aim with the rms ?


Yes - currently you can only grab the Spartan, and you need to hit the attachment 'spike' pretty much in the position shown with good accuracy - I think you have ~10 cm error margin, so even with Eileen doing stationkeeping it's a bit tricky to do.
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Re: Space Shuttle - Development

Postby eatdirt » Sat Nov 16, 2019 10:29 pm

Hi there,
don't know how much this is relevant for uninitialized objects, but the first time, and only the first time, I start the SpaceShuttle on a cleaned .fgfs/ config, I get these warnings

Code: Select all
Nasal runtime error: No such member: new
  at /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1691
  called from: /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1797
Nasal runtime error: No such member: new
  at /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/cue_cards.nas, line 86
  called from: /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/cue_cards.nas, line 213
Nasal runtime error: No such member: new
  at /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/coas.nas, line 19
  called from: /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/coas.nas, line 279
Nasal runtime error: No such member: new
  at /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/PFD/PFD_main.nas, line 184
  called from: /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/PFD/PFD_main.nas, line 1079
Nasal runtime error: No such member: new
  at /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/HUD/HUD_main.nas, line 114
  called from: /home/chris/.fgfs/Aircraft/SpaceShuttle/Nasal/HUD/HUD_main.nas, line 988


Cheers,
Chris
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Re: Space Shuttle - Development

Postby Thorsten » Sun Nov 17, 2019 10:22 am

I currently consider 2019.X broken and focus only on 2018.3.

Basically the errors your describe would be devastating on a wide scale.
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Re: Space Shuttle - Development

Postby eatdirt » Sun Nov 17, 2019 6:30 pm

Yes, I have just seen your post on the forum. And indeed, I am seeing weird stuff on AP on various planes as well :(
I'll report more precise issues there if I manage to isolate them!
thanks.
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Re: Space Shuttle - Development

Postby Thorsten » Sun Nov 17, 2019 6:34 pm

At least for the JSBSim channel issue there should now be a fix - unfortunately Windows nightlies are broken, so I can't test much at the moment, but we'll see whether issues go away or not.
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Re: Space Shuttle - Development

Postby legoboyvdlp » Sun Nov 17, 2019 8:10 pm

The only Nasal error I got was this, in the SRB separation code:

Code: Select all
 Nasal runtime error: floating point error in math.asin()
 1363.32 [ALRT]:nasal        at C:/Users/redpa/Documents/FlightGear/Custom Aircraft/SpaceShuttle/Nasal/stages.nas, line 883
 1363.32 [ALRT]:nasal        called from: C:/Users/redpa/Documents/FlightGear/Custom Aircraft/SpaceShuttle/Nasal/stages.nas, line 364
 1363.47 [ALRT]:nasal      Reading i-loaded stage 2 trajectory display data.
 1483.13 [ALRT]:nasal      Current altitude should be about: 451164.2644287049


Admittedly I was using a totally non-sensical trajectory (a 85 degree inclination with 1 degree offset launched from Jersey - however, despite exceeding AOA at max-QBAR, I survived (soft-mode helps :D) and it did end up in a... interesting orbit! The only thing that didn't work was the orange trajectory prediction dots on the ASCENT TRAJ 2 which got stuck.

Image

However - the external tanks wouldn't seperate as apparently the SRBs were still connected. I suppose I should expect oddities when I try silly things like these orbits - not so concerned about that.

But - the important thing is that apparently all the various errors have disappeared (unless the stage error was one - I'll try an ordinary launch) - speaking of the HUD, shouldn't it initialise to OFF in the --launch mode?
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Re: Space Shuttle - Development

Postby legoboyvdlp » Sun Nov 17, 2019 8:37 pm

On a standard trajectory launch from KTTS the AOA keeps creeping up towards a positive value; very often resulting in the wing exceeding 10 degrees and sometimes exceeding the bending limits - I've noticed this for a long time but nobody else seems to get it? The X-track and D-inc are -4.7 (increasing) and 1.2 degrees respectively; that certainly can't be right.

Anyway; SRB's separated just fine this time and all looks good - the last commits appear to have fixed any issues there were!
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Re: Space Shuttle - Development

Postby eatdirt » Sun Nov 17, 2019 9:33 pm

@lego, I have this too on 2019.* versions.

But also check that you don't have joysticks, or thrusters command, slightly trim out of zero, I had that a while ago!
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Re: Space Shuttle - Development

Postby legoboyvdlp » Mon Nov 18, 2019 12:12 am

I have no hardware at all - not sure what you mean by the thrusters? The controls should be centered but will make sure next time :? Thank you, anyway.
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Re: Space Shuttle - Development

Postby Thorsten » Mon Nov 18, 2019 8:28 am

However - the external tanks wouldn't seperate as apparently the SRBs were still connected. I suppose I should expect oddities when I try silly things like these orbits - not so concerned about that.


Actually that all sounds like 'the error' - it has the hallmark of a Nasal crash which disabled part of the functions downstream - SRB not separating is *very* worrisome, that should happen under rather general conditions and the only thing to prevent it is a main loop crash.

Same thing with the trajectory predictor getting stuck.
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