Centaur G/G Prime High Energy Upper Stage

[Zachstar]

Amazing work there! Sadly I did not have time to pay much attention to SSU but I have always loved the idea of the G and the alternate universe ideas of its use. (I have memories talking to you over IM about some of them but I may be just imagining things)

Did you ever move away from GMAX?

 

[DaveS]

Did you ever move away from GMAX?

Not really. I use both AC3D and and GMAX. I consider both as tools in a tool box. Both has their uses.

---------- Post added at 07:28 AM ---------- Previous post was at 06:41 AM ----------

Here's a photo from STS-51I showing some of the Centaur-related pipes. They're the ones located on both sides of Bay 13, below the LeaSat in the photo. This is the only photo I have that shows it. Today, nothing exists and the cavities are covered by the same thermal blankets that covers the rest of the payload bay.

 

[DaveS]

Here's a comparison showing the differences between the G Prime version and the G version:

 

[Zachstar]

What use would be G version be instead of the prime? Not much chance of seriously reduced cost so a mission would just scale to use a Star stage at that point no?

 

[Urwumpe]

What use would be G version be instead of the prime? Not much chance of seriously reduced cost so a mission would just scale to use a Star stage at that point no?

It would be a lot more powerful than a PAM and still permit longer payloads than the G Prime.

 

[DaveS]

These are photos that I have gotten through e-mail correspondence with some great and helpful folks at GRC.
A bit of bad news through: These are the only ones available in digital format but I have asked if there are other photos that have not been scanned and if it would be possible to have them scanned and uploaded to the official KSC Media Gallery.

All of the photos is of the Centaur during processing at KSC except one which is I guess of a CISS being installed into the MST of Complex 36A for tanking tests.

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-86PC-0086.jpg

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-86PC-88.jpg

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-86PC-0140.jpg

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-385C-2935 FR# 04.jpg

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-385C-4352 FR# 08.jpg

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-385C-4352 FR# 31.jpg

---------- Post added at 11:30 PM ---------- Previous post was at 09:53 PM ----------

Forgot to post this one, a close up of what I think is the real Galileo spacecraft as it was being hoisted for mating with its Centaur stage:

https://dl.dropbox.com/u/24122088/STSCentaur/108-KSC-86PC-0139.jpg

 

[DaveS]

Here's the latest screenshots of the new Centaur G Prime mesh and textures. Things are coming along fine.

Nearly everything is done except for the FWD adapter avionics boxes and new propellant feed lines to the RL-10's.

 

[Felipi1205]

Can I send my meshes and textures of the new GEP Galileo? You could create some .ini files and use it in your Centaur G/G Upper Stage...

 

[DaveS]

Can I send my meshes and textures of the new GEP Galileo? You could create some .ini files and use it in your Centaur G/G Upper Stage...

No need. The only thing is the interface between the Centaur and Galileo. You can see it in two of the photos linked in a post above. It is the sliver-foil clad cone with the "NASA" and "Galileo" markings. In order to fit on on the Centaur the base should be 2.64 m in diameter.

Ulysses used a different interface looking very much like the FWD Adapter of the Centaur itself with a base diameter of 2.64 m.

 

[Felipi1205]

The problem is that I don't know almost NOTHING about coding, even spacecraft3 isn't so easy... And you know how to use spacecraft3, right? So I could create the interface between the spacecraft and the Centaur, while you work with the spacecraft .ini files...

 

[DaveS]

Since I'm now mostly done with the Centaur G Prime itself, I have moved on to the CISS. One big question is how to set up the cryogenic ducts for proper animation as according to this image from the Centaur G Prime Technical Description document:

 

[Urwumpe]

Since I'm now mostly done with the Centaur G Prime itself, I have moved on to the CISS. One big question is how to set up the cryogenic ducts for proper animation as according to this image from the Centaur G Prime Technical Description document:

"Three gimbal articulated duct" sounds pretty clear to me. It leaves only little room for interpretation in engineering lingo.

"Three gimbal" = There are three gimbals
"Articulated" = It is separated into solid links that move only at the gimbals
"Duct" = Something goes in and the same goes out.

If you look closer to the drawing, you can for example see at the thicker segments of the duct are changing their shape during the rotation.

 

[DaveS]

"Three gimbal articulated duct" sounds pretty clear to me. It leaves only little room for interpretation in engineering lingo.

"Three gimbal" = There are three gimbals
"Articulated" = It is separated into solid links that move only at the gimbals
"Duct" = Something goes in and the same goes out.

If you look closer to the drawing, you can for example see at the thicker segments of the duct are changing their shape during the rotation.

I know that. The question was more about how set up the mesh to support this animation. I'm only familiar with SC3 animations which are pretty basic. Are there any special things we could do through the API?

 

[Urwumpe]

I know that. The question was more about how set up the mesh to support this animation. I'm only familiar with SC3 animations which are pretty basic. Are there any special things we could do through the API?

Sure, many. But for such a simple one-dimensional animation, the SC3 API should already have all that we use, plain precomputed animations and animation intervals.

 

[DaveS]

Sure, many. But for such a simple one-dimensional animation, the SC3 API should already have all that we use, plain precomputed animations and animation intervals.

Here's what is troubling me: In order to do this, each animation component needs to be its own separate meshgroup. This will create visible seams that do not look right or good.

The only way for me to solve this is by merging them into one meshgroup ad welding the vertices. But then I won't be able to animate the components anymore.

Is there any way to do this through the OAPI on vertex level? In that case, no problem exist as the vertices will not change orientation or location as I merge and weld. Animations on the vertex level is something SC3 can't do, just the basic rotate/translate/scale meshgroups.

 

[Urwumpe]

Here's what is troubling me: In order to do this, each animation component needs to be its own separate meshgroup. This will create visible seams that do not look right or good.

That should be no problem if you create proper articulated duct joints. Shall I make you a quick reference drawing, how such joints will likely look like, so you can rework them? I have a general drawing somewhere in an engineering book here.

Is there any way to do this through the OAPI on vertex level? In that case, no problem exist as the vertices will not change orientation or location as I merge and weld. Animations on the vertex level is something SC3 can't do, just the basic rotate/translate/scale meshgroups.

Yes, but that isn't needed. As written above, the duct is "articulated". It isn't one flexible duct, but a duct made of multiple rigid links, like a chain or a (-n articulated) robot arm. Thus also no problem with seams.

 

[DaveS]

That should be no problem if you create proper articulated duct joints. Shall I make you a quick reference drawing, how such joints will likely look like, so you can rework them? I have a general drawing somewhere in an engineering book here.

That would be great!

Yes, but that isn't needed. As written above, the duct is "articulated". It isn't one flexible duct, but a duct made of multiple rigid links, like a chain or a (-n articulated) robot arm. Thus also no problem with seams.

That's what the problem is. Each link will have to be its own separate group and this creates seams. I have included a screenshot of two non-merged and unwelded cylinders that shows the seam between the two.

 

[SiameseCat]

I'm not sure what the problem is. In real life, you would probably have seams or something similar where each of the links meet. One group per link should be fine.

 

[Urwumpe]

That's what the problem is. Each link will have to be its own separate group and this creates seams. I have included a screenshot of two non-merged and unwelded cylinders that shows the seam between the two.

yes, but that isn't a joint.

Look for example here for inspiration:

http://www.sabird-bellows.co.uk/Images/aerospace.pdf

(By the drawing, I suspect a simple bellow joint, possibly externally covered)

 

[DaveS]

yes, but that isn't a joint.

Look for example here for inspiration:

http://www.sabird-bellows.co.uk/Images/aerospace.pdf

(By the drawing, I suspect a simple bellow joint, possibly externally covered)

Could you mark on the rotation system drawing where you think the different rotation joints are located?