Space Shuttle Ultra 1.25 Revision B development

[Urwumpe]

Well, I do know that the null X axis is located 236" forward of nose tip of the orbiter. The Xo/Yo planes meet each other at Zo 400".

Aaaaaaaaaaaaaaaaaaaaaaaaah!

Mathematics!!!!

:focus:

 

[DaveS]

Aaaaaaaaaaaaaaaaaaaaaaaaah!

Mathematics!!!!

:focus:

So to make things easier: In orbiter mesh coordinates, the center of the mesh is not the center of the coordinate system.

The mesh for proper placement according to the shuttle orbiter coordinate system should be located 236" aft of the fore/aft center point(-5.9 m on Orbiter Z axis), while the shuttle orbiter Y axis should stay at 0(0 m on Orbiter X axis) and the shuttle orbiter Z axis should be located 400"(10 m) above the Orbiter Y axis.

So that gives us the true mesh coordinates of 0, 10 ,-5.9. Does that make sense?

 

[Urwumpe]

The mesh for proper placement according to the shuttle orbiter coordinate system should be located 236" aft of the fore/aft center point(-5.9 m on Orbiter Z axis), while the shuttle orbiter Y axis should stay at 0(0 m on Orbiter X axis) and the shuttle orbiter Z axis should be located 400"(10 m) above the Orbiter Y axis.

So that gives us the true mesh coordinates of 0, 10 ,-5.9. Does that make sense?

I am not sure about the Y=10, this would place it a bit high above the stack, wouldn't it make more sense to be -10 and thus below the Orbiter in orbit?

if putting this at -10, the IMUs and the AAs would be around the orbiter centerline in orbit:

In body coordinates and inches:

AA 1 : X0=+382.8 Y0 = -06.8 Z0 = +398.2
AA 2 : X0=+381.7 Y0 = +05.6 Z0 = +406.4
AA 3 : X0=+381.7 Y0 = +11.6 Z0 = +406.4
AA 4 : X0=+382.8 Y0 = -12.8 Z0 = +398.2

IMU 1 : X0=+419.187 Y0 = -13.75 Z0 = +422.0
IMU 2 : X0=+419.187 Y0 = +00.00 Z0 = +422.0
IMU 3 : X0=+419.187 Y0 = +13.75 Z0 = +422.0

 

[DaveS]

I am not sure about the Y=10, this would place it a bit high above the stack, wouldn't it make more sense to be -10 and thus below the Orbiter in orbit?

To quote my source for the numbers:

In the Orbiter, the horizontal Xo/Yo reference plane is located at Zo 400, which is 336.5 inches above the ET horizontal Xt/Yt reference plane located at Zt 400.

 

[Urwumpe]

To quote my source for the numbers:

Aren't X0, Y0, Z0 relative to the ET plane? (Emphasis on the 0)

 

[DaveS]

Aren't X0, Y0, Z0 relative to the ET plane? (Emphasis on the 0)

Found this little note in the online Shuttle News Reference Manual: "The Z axis of each point within all elements of the shuttle except the SRBs is positive, with Z = 0 located below the element."

And after some more analysis of the problem, it seems like Zo is aligned with the very center of the orbiter nose tip, that could explain the Zo position relative to the ET nose tip at Zo 400.

---------- Post added at 03:05 PM ---------- Previous post was at 02:57 PM ----------

This is from the SCOM on the location of the Z axes: "Also, the orbiter,
external tank, and shuttle system center X, Z
planes coincide."

 

[tblaxland]

Aren't X0, Y0, Z0 relative to the ET plane? (Emphasis on the 0)

The naming convention is XO (O=Orbiter), XT (T=Tank), XB (B=Booster).

From what I can find, the tank "reference plane" ZT=400 is coincident with the booster "reference plane" ZB=0, suggesting that this plane passes through the centreline of the ET and the centreline of the boosters. The "reference plane" ZO=400 is 336.5" above this.

If you can answer the following questions, I think we can readily derive a vector from the SSU coordinate origin to the NASA Space Shuttle Orbiter Coordinate System (the coordinate system referred to below is the left-handed SSU system with the origin at the centre of gravity of the free-flying orbiter):
1. What is the distance from the SSU +Z axis to the ET centreline (alternatively put, what is the Y-coordinate of the ET centreline in SSU)? Or, if it is easier to answer, what is the Y-coordinate of the top of the SSU payload doors or the top of the tail (I can measure these from the NASA drawings)?
2. What is the Z-coordinate of the nose tip or the aft-most point of the tail?

 

[DaveS]

Any update the VAB?

 

[Urwumpe]

Any update the VAB?

Work is a bit slower now than during the weekend, but getting slowly done, though I currently also divert some time getting the dreaded "ten instruction assembler" work to the spec and write a manual for it. Want to have the chapter "MDM" closed for a while.

BTW - do you know if they work in the VAB at night?

 

[DaveS]

BTW - do you know if they work in the VAB at night?

Yep. Most of the heavy lifts are done during second shift which is the night shift. Here's some times for the STS-131 S0004(Orbiter/ET mate): http://www.orbiter-forum.com/showpost.php?p=155777&postcount=15

 

[Urwumpe]

Ok, then I don't need to change the sound levels inside the VAB for different times of the day. But a local time clock might be useful.

---------- Post added 03-18-10 at 03:53 PM ---------- Previous post was 03-17-10 at 10:42 PM ----------

One request - Can you also make the tools and slings used for stacking the Ares I-X (and likely also the Ares-I)? We could then also use the VAB for this one.

Also, since the VAB mesh contains the LCC as well, should I maybe merge the functions of the VAB with the LCC functions in SSU?

Another thing I saw is that the cranes are part of the external mesh, I would say they are better used in the internal mesh.

 

[DaveS]

One request - Can you also make the tools and slings used for stacking the Ares I-X (and likely also the Ares-I)? We could then also use the VAB for this one.

Actually, except for the Simulated CEV/LAS, Ares 1X was stacked using the SRM segment sling. The Simulated CEV/LAS was stacked using a sling called the "bird cage" due it's similar appearance to a bird cage.

Also, since the VAB mesh contains the LCC as well, should I maybe merge the functions of the VAB with the LCC functions in SSU?

I think that should be done.

Another thing I saw is that the cranes are part of the external mesh, I would say they are better used in the internal mesh.

I'll move them as soon as I'm done with the orbiter sling set.

 

[Urwumpe]

I'll move them as soon as I'm done with the orbiter sling set.

OK, I'll just do the cranes at a lower level then. Do you think it would be possible to make a crane cab VC for each crane?

 

[DaveS]

OK, I'll just do the cranes at a lower level then. Do you think it would be possible to make a crane cab VC for each crane?

Unfortunately I lack any reference photos of the interior of the cabs.

 

[Urwumpe]

Unfortunately I lack any reference photos of the interior of the cabs.

I also can't help you yet. I have only found out so far, that the 250 ton cranes have each cost 2,000,000 USD back then (a lot of money today) and are unique cranes, that have been produced only for the VAB and with special features for assembling rockets (like being able to hold a full load for 30 minutes without applying brakes)

What I am searching is, which company got the contract for the VAB cranes. Of course, it would be better if we could find one of the workers who operate the cranes and ask him for help...

Correction: Found the manufacturer... Colby Cranes, from Seattle.

http://www.hq.nasa.gov/pao/History/SP-4204/ch12-4.html

 

[DaveS]

Correct. The original cranes in the VAB(175/250 ton) was manufactured by Colby Crane. They also got the contract for the Apollo LUT hammerhead cranes as well. The hammerhead cranes were retired in 1994 due to cost reasons. The newer 325 ton cranes were manufactured by Ederer Crane company.

The transfer aisle crane has two hooks, 1 big one capable of 175 ton lifts and a smaller one capable of 25 ton lifts.

 

[DaveS]

Here's two screenshots of the almost completed orbiter sling set:

 

[DaveS]

Checked in the altered meshes. As bonus is an incomplete version of the Low Bay structural interior.

 

[Logifech]

Wow lokks very cool good job

 

[DaveS]

The orbiter sling set is done! Urwmupe, how do you want them? The forward slings and the aft sling separately? Or both of them in the same mesh file?