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Space Shuttle - Bugfixes

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Re: Space Shuttle - Bugfixes

Postby wkitty42 » Sun Jan 12, 2020 6:05 pm

eatdirt wrote in Sat Jan 11, 2020 10:34 pm:Gotcha!!! AI? FlightPlan while I was trying to dock?? :shock:

apparently you (still) have AI enabled... you should probably turn them off for shuttle stuffs like turning off active weather so it doesn't be requesting so many METAR from NOAA as you circle the earth ;)
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
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Re: Space Shuttle - Bugfixes

Postby Thorsten » Sun Jan 12, 2020 6:25 pm

notice that there are no further decimals after 0.45,


That'd be because it's the limit to which the engine will go - it's clipped to that limit.

So the value seeps in to the commanded value - which means we need to find out where it comes from. Let's focus on engine[0]

What do

/fdm/jsbsim/propulsion/engine[0]/pitch-angle-rad-cmd
/fdm/jsbsim/propulsion/engine[0]/pitch-angle-rad-rsys
/fdm/jsbsim/propulsion/engine[0]/pitch-angle-rad-gsys
/fdm/jsbsim/systems/vectoring/vectoring-rate-master
/fdm/jsbsim/systems/vectoring/vectoring-gimbal-master
/fdm/jsbsim/systems/vectoring/aero-engine-stow-cmd
/fdm/jsbsim/systems/vectoring/ssme-repos-enable

say in both cases?

What is the value of

/fdm/jsbsim/systems/fcs/control-mode
?
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Sun Jan 12, 2020 8:50 pm

Here we go, first line are with joystick held.

/fdm/jsbsim/propulsion/engine/pitch-angle-rad-cmd=-0.45
/fdm/jsbsim/propulsion/engine/pitch-angle-rad-rsys=-0.45 (<------- this one is set already before putting hydraulic pressure to HIGH)
/fdm/jsbsim/propulsion/engine/pitch-angle-rad-gsys=0
/fdm/jsbsim/systems/vectoring/vectoring-rate-master=1
/fdm/jsbsim/systems/vectoring/vectoring-gimbal-master=0
/fdm/jsbsim/systems/vectoring/aero-engine-stow-cmd=0
/fdm/jsbsim/systems/vectoring/ssme-repos-enable=1

++++++++++++++++++++++++++++++++++++++++++++++++++++++++

/fdm/jsbsim/propulsion/engine/pitch-angle-rad-cmd=-0.33...
/fdm/jsbsim/propulsion/engine/pitch-angle-rad-rsys=-0.33...(<------- this one is set already before putting hydraulic pressure to HIGH)
/fdm/jsbsim/propulsion/engine/pitch-angle-rad-gsys=0
/fdm/jsbsim/systems/vectoring/vectoring-rate-master=1
/fdm/jsbsim/systems/vectoring/vectoring-gimbal-master=0
/fdm/jsbsim/systems/vectoring/aero-engine-stow-cmd=0


/fdm/jsbsim/systems/vectoring/ssme-repos-enable=1
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Sun Jan 12, 2020 9:02 pm

@Thorsten, thanks, the SRB sep works now with 3 EO.

But as far as I can tell, I cannot switch it to manual? They always auto-separate, triggering also the ET sep, and indeed we are dead.

Would it be possible to have the manual option? I'd like to separate the SRBs by hand, and maintain the ET after that for a while to separate it later, maybe in a -2 degrees-like attitude. In fact, I am just trying to explore if there is an altitude/attitude/velocity at which we could manually detach the ET without blowing, and then fly to bailout.
For the time being, I am able to roll-up and fly almost horizontally with the booster attached, so it looks possible to "fly" the Shuttle provided detachment of all the bombs can be made :)
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Sun Jan 12, 2020 9:33 pm

Sorry to spam again, but since I've been making a lot of test, here a new one, I've disabled AI this time, but this one is new. In the sim, the rdv navigation windows got frozen and it was also impossible to change view. Maybe I should test if this one in particular happens again with Richards' suggestion.

Code: Select all
1391.14 [ALRT]:nasal      Starting targeting routines
 1391.86 [ALRT]:nasal      Nasal runtime error: undefined symbol: delta_lon
 1391.86 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/rel_orbital.nas, line 582
 1391.86 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.86 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/coas.nas, line 204
 1391.86 [ALRT]:nasal      Nasal runtime error: No such member: run
 1391.86 [ALRT]:nasal        at /usr/share/games/flightgear/Nasal/orbital_target.nas, line 266
 1391.92 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.92 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1988
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.97 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1988
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.97 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1926
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: _loop_
 1391.97 [ALRT]:nasal        at /usr/share/games/flightgear/Nasal/screen.nas, line 383
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.97 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1926
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.97 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1988
 1391.97 [ALRT]:nasal      Nasal runtime error: No such member: update
 1391.97 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/housekeeping.nas, line 1926
 1393.03 [ALRT]:nasal      Nasal runtime error: No such member: update
 1393.03 [ALRT]:nasal        at /home/chris/.Aircraft/SpaceShuttle/Nasal/canvas/cdlg_rendezvous.nas, line 442
 1395.05 [ALRT]:nasal      MFD2: Power consumption is now: 37.5 W
 1395.05 [ALRT]:nasal      MDU Mode MFD2 9
 1395.16 [ALRT]:nasal      MFD2: Power consumption is now: 35 W
 1395.16 [ALRT]:nasal      MDU Mode MFD2 8
 1395.24 [ALRT]:nasal      MFD2: Power consumption is now: 32.5 W
 1395.24 [ALRT]:nasal      MDU Mode MFD2 7
 1395.33 [ALRT]:nasal      MFD2: Power consumption is now: 30 W
 1395.33 [ALRT]:nasal      MDU Mode MFD2 6
 1395.53 [ALRT]:nasal      MFD2: Power consumption is now: 27.5 W
 1395.53 [ALRT]:nasal      MDU Mode MFD2 5
 1396.82 [ALRT]:nasal      Nasal runtime error: No such member: raise
 1396.82 [ALRT]:nasal        at /usr/share/games/flightgear/Nasal/canvas/gui.nas, line 471
 1396.85 [ALRT]:nasal      Nasal runtime error: No such member: move
 1396.85 [ALRT]:nasal        at /usr/share/games/flightgear/Nasal/canvas/gui.nas, line 505
 1396.85 [ALRT]:nasal      Nasal runtime error: No such member: move
 1396.85 [ALRT]:nasal        at /usr/share/games/flightgear/Nasal/canvas/gui.nas, line 505
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Re: Space Shuttle - Bugfixes

Postby legoboyvdlp » Sun Jan 12, 2020 10:19 pm

That's bizarre... is it reproducible?

The former -- update_tank is not called except when delta_lon is equal to 0.0 - so something is _badly_ amiss somewhere... that's like memory getting overwritten or something...
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Re: Space Shuttle - Bugfixes

Postby Thorsten » Mon Jan 13, 2020 6:49 am

But as far as I can tell, I cannot switch it to manual? They always auto-separate, triggering also the ET sep, and indeed we are dead.


At least for me manual separation works fine (you have to push the button while they're still burning of course, otherwise auto-sep is triggered). The Shuttle has no option to defer separation (the switch position is called MAN/AUTO because manual override is only available before AUTO triggers).

Also, 3EO automatically triggers contingency logic, which means an emergency ET-sep. You have relatively high aerodynamical forces during first stage - and you have a big and heavy ET to yank around with absolutely insufficient thrusters. Not a good combo.

Again, none of this helps you since you have no attitude control to speak of once you separate...

Oh, and you're out of trim. Badly...

The former -- update_tank is not called except when delta_lon is equal to 0.0 - so something is _badly_ amiss somewhere... that's like memory getting overwritten or something...


Yes, that's remniscent of the one I posted on the mailing list - a routine mysteriously running before its class is even initialized, for which there's no available code path. Something is messed up inside Nasal.
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Mon Jan 13, 2020 7:43 am

Not a good combo


Yes, indeed :) Just for the purpose of the sim, I've noticed that the aerosurfaces remain locked once the tumbling stops, even after transitioning to OPS 602/603. But, anyway, after sep, with the spin triggered by the trims, the Shuttle should certainly be ripped apart.

Edit: Oh, I've find a way to sep the boosters and tanks by hand by switching to BFS just before, that's not so bad, it is flyable, but the trims are bad. It seems that BFS switches to ENTRY mode and does something funny with the elevons, one up, one down.
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Re: Space Shuttle - Bugfixes

Postby legoboyvdlp » Mon Jan 13, 2020 8:21 am

@eatdirt is /controls/shuttle/ET-static-model true or false when those messages appear? Or are they just random?
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Re: Space Shuttle - Bugfixes

Postby Thorsten » Mon Jan 13, 2020 9:16 am

I've noticed that the aerosurfaces remain locked once the tumbling stops, even after transitioning to OPS 602/603


Yes, the transition to airfoils is driven by sensed dynamical pressure, not by a major mode transition even if you are in Aerojet DAP.

It seems that BFS switches to ENTRY mode and does something funny with the elevons, one up, one down.


BFS does basically nothing for a contingency abort, that's not in the software.

Again, there's no software or DAP implemented for a contingency 3EO BLUE situation, so in all likelihood you're fighting against the 3EO GREEN logic or whatever BFS happens to think you're trying to do.
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Re: Space Shuttle - Bugfixes

Postby Thorsten » Mon Jan 13, 2020 9:23 am

Okay, further inward with the engine gimbals.

It seems the correct system is active (rate controller) and all other contributions are zero as they should be (I need to check whether repos enable should be one, but anyway the contribution itself is zero).

/fdm/jsbsim/propulsion/engine/pitch-angle-rad-rsys

is computed from

/fdm/jsbsim/systems/vectoring/SSME-pitch
/fdm/jsbsim/systems/vectoring/SSME-left-roll
/fdm/jsbsim/propulsion/engine[0]/pitch-to-CoG

what do they read, and what are the values of

/fdm/jsbsim/systems/vectoring/roll-rate-error
/fdm/jsbsim/systems/vectoring/yaw-rate-error

in both cases?
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Mon Jan 13, 2020 10:35 pm

Joystick held down:

/fdm/jsbsim/systems/vectoring/SSME-pitch <---- this guy is a directory and inside there is:

initial-integrator-value ="" (double)

/fdm/jsbsim/systems/vectoring/SSME-left-roll=-0.034...
/fdm/jsbsim/propulsion/engine[0]/pitch-to-CoG=-0.2852... (always increase in its last decimals!?)
/fdm/jsbsim/systems/vectoring/roll-rate-error=-1e-14 <--- fluctuate around this
/fdm/jsbsim/systems/vectoring/yaw-rate-error=-3e-11 <---fluctuate


+++++++++++++++++++++++++++++++++++++++++

joystick unhold, the same, it is not a copy-paste mistake. Looks like the joystick is bypassing calculations!?

/fdm/jsbsim/systems/vectoring/SSME-pitch <---- this guy is a directory and inside there is:

initial-integrator-value ="" (double)

/fdm/jsbsim/systems/vectoring/SSME-left-roll=-0.034...
/fdm/jsbsim/propulsion/engine[0]/pitch-to-CoG=-0.2852... (always increase in its last decimals!?)
/fdm/jsbsim/systems/vectoring/roll-rate-error=-1e-14 <--- fluctuate around this
/fdm/jsbsim/systems/vectoring/yaw-rate-error=-3e-11 <---fluctuate
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Mon Jan 13, 2020 10:38 pm

is /controls/shuttle/ET-static-model true or false when those messages appear? Or are they just random?


It was in orbit. I've gotten these messages, and the associated freeze of the rdv window (and views) only twice in about 20 runs or so. But next time it occurs, I'll check the boolean!
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Re: Space Shuttle - Bugfixes

Postby Thorsten » Tue Jan 14, 2020 7:01 am

/fdm/jsbsim/systems/vectoring/SSME-pitch <---- this guy is a directory and inside there is:


So all is the same except the integrator... what we need to do to investigate the value of it is to add an output - currently it looks like (Systems/thrust_vectoring.xml)

Code: Select all
      <pid name="systems/vectoring/SSME-pitch">
         <input>systems/vectoring/pitch-rate-error</input>
         <kp> 2.0 </kp>
         <ki> 1.5 </ki>
         <kd> 0.1</kd>
         <clipto>
            <min> -0.17 </min>
                 <max>  0.17 </max>
         </clipto>
      </pid>


and you can change this to

Code: Select all
      <pid name="systems/vectoring/SSME-pitch">
         <input>systems/vectoring/pitch-rate-error</input>
         <kp> 2.0 </kp>
         <ki> 1.5 </ki>
         <kd> 0.1</kd>
         <clipto>
            <min> -0.17 </min>
                 <max>  0.17 </max>
         </clipto>
         <output>systems/vectoring/SSME-pitch-value</output>
      </pid>


which should make it readable as /fdm/jsbsim/systems/vectoring/SSME-pitch-value.

But let's assume for the moment that that's where the difference is as all else looks the same. We'd then want to look at what defines the error, i.e.

/fdm/jsbsim/velocities/q-rad_sec
/fdm/jsbsim/fcs/elevator-cmd-norm-css
/fdm/jsbsim/systems/ap/launch/autolaunch-pitch-channel
/fdm/jsbsim/systems/ap/launch/pitch-cmd

The only stick-driven property that's there is the elevator-cmd-norm-css, but by rights this should be multiplies with a zero, so here we come to the heart of the mystery.
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Re: Space Shuttle - Bugfixes

Postby eatdirt » Tue Jan 14, 2020 8:55 pm

Joystick held:

/fdm/jsbsim/systems/vectoring/SSME-pitch-value=-0.17 (locked to max!?)
/fdm/jsbsim/velocities/q-rad_sec=-1.49e-9
/fdm/jsbsim/fcs/elevator-cmd-norm-css=-1 but if I let the joystick goes to rest =0
/fdm/jsbsim/systems/ap/launch/autolaunch-pitch-channel=1
/fdm/jsbsim/systems/ap/launch/pitch-cmd=0

++++++++++++++++++++++++++++++++++++++++++
Joystick at rest, not touching it.

/fdm/jsbsim/systems/vectoring/SSME-pitch-value=-0.0149...
/fdm/jsbsim/velocities/q-rad_sec=-1.40e-9
/fdm/jsbsim/fcs/elevator-cmd-norm-css=0.05 (weird?!?) <--------- if I take the joystick, pull it down it goes to -1. If I let the joystick going back to rest, it becomes =0.
/fdm/jsbsim/systems/ap/launch/autolaunch-pitch-channel=1
/fdm/jsbsim/systems/ap/launch/pitch-cmd=0
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