SSU Development thread (4.0 to 5.0) [DEVELOPMENT HALTED DUE TIME REQUIREMENTS!]

[GLS]

Any issues with me unstickying the IUS and Centaur G threads? We have quite many sticky threads right now and I think those are not part of 5.0 work right now.

Fine with me.

 

[Urwumpe]

Like the star trackers.

Do we have the shutters for the star trackers as well? those are in front of the first lens and close when a hot bright object is around. Both types of star trackers use the same shutter mechanism.

 

[DaveS]

Do we have the shutters for the star trackers as well? those are in front of the first lens and close when a hot bright object is around. Both types of star trackers use the same shutter mechanism.

Only the doors. I've never seen the shutters. Probably because all the shots of the star trackers were taken from the ISS and had the actual cameras in shadow.

 

[Urwumpe]

Do we already have ET fast separation by the ET SEP button?

 

[DaveS]

Do we already have ET fast separation by the ET SEP button?

No. AFAIK Fast Sep was never implemented. It does live on in PASS but it isn't accessible. The ET Sep PB on C3 only commands a normal ET sep.

 

[Urwumpe]

No. AFAIK Fast Sep was never implemented. It does live on in PASS but it isn't accessible. The ET Sep PB on C3 only commands a normal ET sep.

Had seen the sequencing for fast sep again in the documents next to the star tracker data and wondered where this went. After all, it would have been a pretty "exciting" way to end a mission.

 

[GLS]

I haven't checked but I think the ET Sep PB currently only overrides the sep limits.

---------- Post added at 07:12 PM ---------- Previous post was at 07:11 PM ----------

Had seen the sequencing for fast sep again in the documents next to the star tracker data and wondered where this went. After all, it would have been a pretty "exciting" way to end a mission.

Yeah, but open the star tracker doors first, so they can see the fireworks. :rofl:

 

[DaveS]

I checked the SCOM and it never mentioned Fast Sep in relation to the ET Sep PB. It's only used to manually command ET sep should the auto sequence be inhibited.

 

[Urwumpe]

Yeah, but open the star tracker doors first, so they can see the fireworks. :rofl:

Working on it. :lol: Just the mechanism for now, I have to find out how the GPCs talk to the star trackers. I suspect the GPC has the star table, not the star tracker.

---------- Post added at 23:23 ---------- Previous post was at 20:31 ----------

I am sure, somebody will tell me that I am getting old and forget a lot of important stuff...

But:

Do we really have a PASS TRAJ 1 in MM 102? The old manuals explicitly mention that the Shuttle symbol does not appear in the single PASS TRAJ display until MM 103, contrary to BFS, which has a TRAJ 1 (MM 102) and TRAJ 2 (MM103) display.

Did the PASS also get a TRAJ 1 display later?

 

[GLS]

I am sure, somebody will tell me that I am getting old and forget a lot of important stuff...

But:

Do we really have a PASS TRAJ 1 in MM 102? The old manuals explicitly mention that the Shuttle symbol does not appear in the single PASS TRAJ display until MM 103, contrary to BFS, which has a TRAJ 1 (MM 102) and TRAJ 2 (MM103) display.

Did the PASS also get a TRAJ 1 display later?

I made the new PASS TRAJ 1 (post OI-30 or something), that is similar to the BFS TRAJ 1, sometime ago. Before that there was only a PASS TRAJ 2, which was what we had. I kept the code of that PASS TRAJ 2 in the GeneralDisplays class for future use... when we have more than one version of GPC code... :shrug:

 

[Urwumpe]

I made the new PASS TRAJ 1 (post OI-30 or something), that is similar to the BFS TRAJ 1, sometime ago. Before that there was only a PASS TRAJ 2, which was what we had. I kept the code of that PASS TRAJ 2 in the GeneralDisplays class for future use... when we have more than one version of GPC code... :shrug:

Well, I can't find anything about a PASS TRAJ 1 or 2. Just "LAUNCH TRAJ" and "RTLS TRAJ" in PASS. Even in the latest DPS dictionary. That is what confuses me there. I can't find any change to the OI that made the PASS displays similar to the BFS displays.

 

[GLS]

Well, I can't find anything about a PASS TRAJ 1 or 2. Just "LAUNCH TRAJ" and "RTLS TRAJ" in PASS. Even in the latest DPS dictionary. That is what confuses me there. I can't find any change to the OI that made the PASS displays similar to the BFS displays.

Ok, so initially the PASS only had one ascent display, the XXXXXX TRAJ (XXXXXX = LAUNCH in MM101, ASCENT in 102 and 103, and TAL, ATO or RTLS for aborts). This display showed the trajectory for second stage and RTLS fly back.
The BFS had 3 displays, XXXXXX TRAJ 1, XXXXXX TRAJ 2 (the Xs are the same as above) and RTLS TRAJ 2. The first 2 displays had the trajectory uphill, and the RTLS display had the fly back trajectory.
So for a long time, the crew had to use the BFS to monitor the trajectory during first stage, as the PASS display only showed the trajectory for second stage.

Beginning with OI-32 the PASS got the same displays as the BFS (XXXXXX TRAJ 1 , XXXXXX TRAJ 2 and RTLS TRAJ 2).

Initially SSU only had the original PASS XXXXXX TRAJ display which is commented at the bottom of GeneralDisplays.cpp), and sometime ago I replaced it with the more recent PASS XXXXXX TRAJ 1 and XXXXXX TRAJ 2 displays that we currently have in use (there are no RTLS displays because we don't do that yet :shrug.

---------- Post added at 11:56 PM ---------- Previous post was at 11:54 PM ----------

Yes, I also don't have a "recent" DPS dictionary, but the displays are visible in some SMS photos/videos and (more important) they are shown in the SCOM.

 

[Urwumpe]

OI-32, OI-33 and OI-34 only mention the following changes:

• Lambert Guidance Improvements
• 6x Traj display redesign
• Entry and Ascent Bearing Display additions
• RTLS ET Sep improvements
• Entry Remote Controlled Orbiter (RCO) Capability
• Elimination of old user notes and DRs
• Reduction in Horizontal Sit display code size

 

[GLS]

OI-32, OI-33 and OI-34 only mention the following changes:

• Lambert Guidance Improvements
• 6x Traj display redesign
• Entry and Ascent Bearing Display additions
• RTLS ET Sep improvements
• Entry Remote Controlled Orbiter (RCO) Capability
• Elimination of old user notes and DRs
• Reduction in Horizontal Sit display code size

For sure I know it was after OI-30 (I have a DPS Dictionary for that and it still has the old displays) and before OI-33 (I have a SCOM and it has the new displays). The SCOM has the text associated with the displays in blue, meaning it was changed since the last version, so that's where the OI-32 came from. But it could be OI-31 as well... :uhh:

 

[Urwumpe]

Must be existing in OI-32 already according to the Appendix B in the SCOM.

And the latest DPS Dictionary is OI-30 ... so, maybe it was a OI-31 change, which was the final CAU integration OI and the only one with only CAU related CRs

 

[GLS]

I think I got the filter issue behind, as the output now seems to make sense... and the vehicle doesn't crash. BTW: it now lands itself!
There are still control issues to work out (most likelly in the AerojetDAP side as the reference calculations seem OK), but it doesn't make holes in the ground anymore.
I also (re)added the speedbrake logic, now following what little info is available, but it probably needs some tuning as it seems the "default" position is too high, so speed is below what it should be.
Anyway, it lands!

 

[GLS]

I'm not claiming to know 3D modeling as the folks in the graphics department, but I'm working a potential animation issue with the Rudder/Speedbrake, and I went to check the mesh to make sure the panels are in the correct position (they are), and a few issues jumped out:
> the aft side of the top of the tail has a hole in one side, and the other side doesn't look too healthy either;
> the panels themselves each has 8 faces inside, which might all get optimized away during rendering, but still it's extra stuff that is shipped around and then has to be loaded into memory, etc, etc, etc... In the end the downside might be small, but IMO there is no upside at all in having faces inside things, at least in the final products. :shrug:

I can manually clean the mesh of those extra faces, but I need concurrence from the graphics department to avoid "collisions" with the work going on.

 

[Urwumpe]

I took a look at the MCAs, but after this weekend, I have some bad dreams about four pole relays there. The coarse information about them in the SCOM is rather misleading, looks like the MCAs are very different not just in the number and type of control modules. The claim about them always having 8 control modules is wrong, also they seem to have some custom electronics each for controlling electrical power.

Most control modules we are interested in right now are of the most common four relay type motor control electronics. But there are also modules with 10 relays around, can't tell yet what they are. I can say what function they have, but I can't tell how the relays operate depending on the inputs.

Another factor is that all relays in a MCA are chained by the fourth pole to set a parity status line (When all relays are closed, the line is at 5V) - and there are multiple such lines per MCA and each type has a different number of such "operation status" lines.

Looks like the old plan to have a common class MCA and just configure them for the different instances (FMCA, MMCA, AMCA) won't work well.Looks like we rather need a FMCA, MMCA and AMCA class as well, just like we need different kinds of power electronic modules.

 

[GLS]

I took a look at the MCAs, but after this weekend, I have some bad dreams about four pole relays there. The coarse information about them in the SCOM is rather misleading, looks like the MCAs are very different not just in the number and type of control modules. The claim about them always having 8 control modules is wrong, also they seem to have some custom electronics each for controlling electrical power.

Most control modules we are interested in right now are of the most common four relay type motor control electronics. But there are also modules with 10 relays around, can't tell yet what they are. I can say what function they have, but I can't tell how the relays operate depending on the inputs.

Another factor is that all relays in a MCA are chained by the fourth pole to set a parity status line (When all relays are closed, the line is at 5V) - and there are multiple such lines per MCA and each type has a different number of such "operation status" lines.

Looks like the old plan to have a common class MCA and just configure them for the different instances (FMCA, MMCA, AMCA) won't work well.Looks like we rather need a FMCA, MMCA and AMCA class as well, just like we need different kinds of power electronic modules.

Did you check the big diagrams DaveS posted?

 

[DaveS]

I'm not claiming to know 3D modeling as the folks in the graphics department, but I'm working a potential animation issue with the Rudder/Speedbrake, and I went to check the mesh to make sure the panels are in the correct position (they are), and a few issues jumped out:
> the aft side of the top of the tail has a hole in one side, and the other side doesn't look too healthy either;
> the panels themselves each has 8 faces inside, which might all get optimized away during rendering, but still it's extra stuff that is shipped around and then has to be loaded into memory, etc, etc, etc... In the end the downside might be small, but IMO there is no upside at all in having faces inside things, at least in the final products. :shrug:

I can manually clean the mesh of those extra faces, but I need concurrence from the graphics department to avoid "collisions" with the work going on.

Can you show me these issues with the tail? I just checked myself and didn't note any issues. No holes or anything.