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Author Topic: IMFD 5.1 support/TLI burn  (Read 27047 times)
jarmonik
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« Reply #45 on: December 13, 2007, 03:55:34 PM »

I found and fixed an inaccuracy in the burn timing, the TLI burn should be now working within the limits Jarmo mentioned (+/- 15km in PeA).
Cheers
Tschachim

I don't know what you did but it's just perfect now. Congratulations Tschachim.

Here is my test configuration http://koti.mbnet.fi/jarmonik/A11TLI.scn

Ignition: 02:45:08
Offsets:  Lon -1.9,  Lat 6.2  Rad 9.324M

Just open ApolloMFD over the Map program.  I ended up 12km higher orbit than targeted 140km. Also I suppose it is important that the flight data is transfered into ApolloMFD under 1x time acceleration. There is unknown anomaly that will effect into a dV calculations under acceleration.

Jarmo
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jarmonik
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« Reply #46 on: December 14, 2007, 02:32:22 AM »

Hi,

I have done some more testing with NASSP and latest beta of Orbiter.  NASSP will build, link and run OK (at-least visuals). Only problem that I was able to detect is related in ApolloMFD/IMFD/SIVB program that goes dead after pressing SIVB button. It doesn't show any status information or errors. Also it's not possible to reset and restart SIVB program. (Status is IDLE before pressing SIVB)The other program, using the REQ button, seems to work fine. (Of course, this problem doesn't happen under 2006 release)

Also the anomaly that I mentioned earlier occurs only when the attitude control is active (attitude keeping) also it is somehow related in gravity-gradient torque. Also it will occur sameway under IMFD attitude control as well as NASSP attitude control. But why it is depended about time acceleration.
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Tschachim
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« Reply #47 on: December 14, 2007, 09:31:54 AM »

Hi Jarmo,

thanks for your kind words!

Also I suppose it is important that the flight data is transfered into ApolloMFD under 1x time acceleration.

Yes, especially the last transfer 2s before the burn starts, but also while any engine is running (J-2 or APS). The S-IVB automatically sets the time acceleration to 1 at 9:38 minutes before ignition and changes it's attitude to the burn attitude. After the attitude is stable I typically switch to time acceleration 10x and wait for the 2nd automatic switching to time acceleration 1x at about 100s before the burn. Shortly after that the ullage thrust starts and I do not use time acceleration until the burn is finished.

I have done some more testing with NASSP and latest beta of Orbiter.  NASSP will build, link and run OK (at-least visuals).

Wow, thanks for testing, last time I tried (it's a while ago) it was crashing all over the place because of not-yet implemented animation functions in the beta, looks like I should try again sometime...

Only problem that I was able to detect is related in ApolloMFD/IMFD/SIVB program that goes dead after pressing SIVB button. It doesn't show any status information or errors...

No clue, I'd need to debug that, perhaps just another beta bug...

Also the anomaly that I mentioned earlier occurs only when the attitude control is active (attitude keeping) also it is somehow related in gravity-gradient torque. Also it will occur sameway under IMFD attitude control as well as NASSP attitude control. But why it is depended about time acceleration.

Do you refer to the "time acceleration affects dV calculations" anomaly from your last post? With the S-IVB any attitude change (and also station keeping against gravity-gradient torque) has a quite huge translational component because of the "non-CoG centered" APS (= S-IVB RCS) and this effect is bigger with time acceleration because of the longer time steps, which cause bigger thruster settings. But this is S-IVB specific, of course and shouldn't happen with the Delta Glider for example, I'm not sure if that is related to the anomaly...

Cheers
Tschachim
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jarmonik
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« Reply #48 on: December 15, 2007, 03:34:02 AM »

Do you refer to the "time acceleration affects dV calculations" anomaly from your last post? With the S-IVB any attitude change (and also station keeping against gravity-gradient torque) has a quite huge translational component because of the "non-CoG centered" APS (= S-IVB RCS) and this effect is bigger with time acceleration because of the longer time steps, which cause bigger thruster settings. But this is S-IVB specific, of course and shouldn't happen with the Delta Glider for example, I'm not sure if that is related to the anomaly...

Actually Yes, And I think I was able to solve it.  There was a trigger that caused to abort and restart some calculations when the vessel had lost some mass (any mass).
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jc121081
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« Reply #49 on: December 15, 2007, 09:37:49 AM »

Here is a quick procedure to perform TLI in Apollo 8 vAGC scenario using the IMFD/PAMFD combo that I'm going to include in the next flightplan I'm composing. Even with historical times, it works like a charm.  Thumbs Up

Open Interplanetary MFD
Click "MNU"
Click "MOD" (Configuration)
Click "NXT" until "LambertAP Mode" is selected
Click "+" to select "Apollo P30"
Click "MNU"
Click the "Course" button
Ensure "Target Intercept" is highlighted and click "Set"
Click "NXT" until "Realtime" is highlighted
Click "+" to select "Off-Axis"
Click "PRV" until "TEj" is highlighted
Click "+" or "-" to change the Tej to "GET 2:50:37" and use "Adj" to change the increments as necessary
Click "NXT" until "TIn" is highlighted
Click "+" or "-" to change the TIn to "GET 69:08:20" and use "Adj" to change the increments as necessary
*If you started the scenario from pre-launch, you may need to add 3 hours to the TEj and TIn times
Open ProjectApollo MFD
Click "IMFD"
Click "SIVB"

Regards,
jc121081
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jarmonik
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« Reply #50 on: December 15, 2007, 09:59:28 AM »

Here is a quick procedure to perform TLI in Apollo 8 vAGC scenario using the IMFD/PAMFD combo that I'm going to include in the next flightplan I'm composing. Even with historical times, it works like a charm.  Thumbs Up

It's great to hear that it works in vAGC scenarios as well. Happy

Here is unofficial beta of IMFD: http://koti.mbnet.fi/jarmonik/IMFD51c.zip
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Coussini
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« Reply #51 on: December 15, 2007, 10:48:43 AM »

Great news Jarmonik, thanks so much  Thumbs Up
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Have a nice day
jc121081
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« Reply #52 on: December 15, 2007, 12:50:04 PM »

I like the offset procedure you included. Good job, Jarmo! Thumbs Up
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jarmonik
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« Reply #53 on: December 15, 2007, 08:03:47 PM »

It looks like there are a great failures in 5.1c so I have uploaded 5.1d to fix them.

http://koti.mbnet.fi/jarmonik/Orbiter.html
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lassombra
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« Reply #54 on: December 16, 2007, 12:34:33 AM »

Alright, I've committed a slight bugfix/improvement to the Apollo MFD.  It is now capable of extracting the Mission Time through the Crawler Transporter.  It doesn't do anything else in that state obviously.  The other major change is one that had the potential to cause a CTD in the, admittedly unlikely (but still happened to me), event that someone hit the sequence of buttons to trigger a TLI burn program while focused on another vessel.

To fix it, I simply completely disabled the buttons and keys when not on the Saturn.
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My current Project Apollo work:

Quickstart to the Moon initiative (Quickstart_to_the_Moon): Done through earth orbit.  Working on new method of calculating TLI.

Checklist Controller: 
  • MFD Interface 99%(Minor cleanup and future features remain)
  • Panel Interface 99%
  • Excel interface and logic 99%
  • LEM Event code.0%
  • DSKY Interface code. Framework complete, creating "buttons"
  Approximately 80% done. (Checklist Controller
nickel
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« Reply #55 on: January 04, 2008, 08:42:22 AM »

Hello together!  Happy
Am new here and I have real problems with the IMFD 5.1 clearly.
I would like to work with the IMFD 5.1.
But I dont know to what steps I need to keep on mercur for example, mars or Venus fly.
I have already tried a number of tutorials, unfortunately with not much success. To fly to the moon, it worked. But on other planets, unfortunately, not yet.  Embarassed

I hope someone can help me and tell me what steps I must be respected so that it works.

Greeting  Happy
« Last Edit: January 05, 2008, 07:12:11 AM by nickel » Logged
Tschachim
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« Reply #56 on: April 13, 2008, 05:15:34 PM »

With my last CVS commit I also updated the IMFD interface to support the latest version, IMFD 5.1g. The TLI burn now works like this:

* Start the "Apollo 11 Quickstart - Launch" scenario
* Launch to LEO automatically as usual
* Open IMFD
* Press MNU and open the Course - Target Intercept program
* Open ProjectApolloMFD in a different MFD
* Press IMFD and then SIVB
* Wait until the burn is finished, do not close any of the MFDs until the burn started.
* You'll arrive over the landing site in a periapsis altitude of about 100 km at the Moon at about GET +75h.

That's all, I don't get it more easy.  Happy

Cheers
Tschachim
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lassombra
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« Reply #57 on: April 13, 2008, 10:14:24 PM »

this is great news tschachim...  I am curious how you managed to automate the whole thing (so that when I get back to working on the quickstart to the moon checklist, I can implement this feature for other missions as well).
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My current Project Apollo work:

Quickstart to the Moon initiative (Quickstart_to_the_Moon): Done through earth orbit.  Working on new method of calculating TLI.

Checklist Controller: 
  • MFD Interface 99%(Minor cleanup and future features remain)
  • Panel Interface 99%
  • Excel interface and logic 99%
  • LEM Event code.0%
  • DSKY Interface code. Framework complete, creating "buttons"
  Approximately 80% done. (Checklist Controller
Tschachim
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« Reply #58 on: April 14, 2008, 07:38:06 AM »

I am curious how you managed to automate the whole thing (so that when I get back to working on the quickstart to the moon checklist, I can implement this feature for other missions as well).

Yeah, that's the point actually, all that is based on a bunch of settings in the scenario, which are transferred to IMFD: http://nassp.sourceforge.net/wiki/Scenario_File_Options#Mission_parameter_options

For the offset configuration I calculated proper values with IMFD for Apollo 11 and put them to the scenario, so this is something which needs to be done by a developer mission per mission...

Cheers
Tschachim
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bluespace88
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« Reply #59 on: April 14, 2008, 07:46:00 AM »

so this was a feature that IMFD included and only needed extra lines in the scenario file?
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