[Question] Velcro Rocket noob; attaching a custom payload to Velcro Delta-IV

[AlfalfaQc]

Hi everyone, I'm trying to understand how to attach a custom payload to the Delta IV Heavy Launcher using Velcro Rocket but I don't get it. I think VR is the best way to do it but I don't understand how it works. If anyone could help me with VR or have a better (easier) add-on that I could use, please let me know.

Thanks
AlfalfaQc

[sputnik]

What have you tried so far?

I don't have the scenario with me, but...

There's a line in the Delta-IV Heavy specification that reads:

PAYLOAD probe probe probe ....<string of numbers>

That is a CVEL specification string. Here's what it means and does: http://www.orbiterwiki.org/wiki/CVEL

Short short version:
Change the first "probe" to reflect what you'd like your new payload to call itself when released.
Change the second "probe" to point to the .cfg file defining the vessel, normally in Orbiter/Config/Vessels.
Change the third "probe" to point to the .msh file, normally in Orbiter/Meshes.

Then it will probably appear in the wrong place, so play with the first three numbers in the string until it looks right. Don't forget to change the mass, too.

[AlfalfaQc]

Ok, but where do I fins the file in which I change the parameters? I know nothing about programming so I don't really get what do you mean, maybe when I see the file I will understand.

Thanks for the help
AlfalfaQc

[meson800]

To find the the CVEL string, you have to edit the scenario file in which it resides.

To find the scenario file, first find where it is in the main orbiter launchpad. If the scenario is in Velcro -- Launch Vehicles
then you will find the scenario file in path_to_orbiter/Velcro/Launch Vehicles/SCENARIO_NAME_HERE.scn

The .scn file is just a text file, so open it with notepad and find the CVEL string like sputnik said.

Hope this helps,
meson800

[AlfalfaQc]

Ok, but if it is not in the Velcro scenario, can I still modify the file, or do I have to copy it from the original Delta Heavy and put it in the Velcro file?

Edit: I think I found the line:
Delta4HP:delta4/Delta4HP
STATUS Landed Earth
POS -80.5646000 28.5314000
HEADING 30.00
AFCMODE 7
PRPLEVEL 0:1.000000
NAVFREQ 0 0
PAYLOAD delta4/sat2
MESH delta4/sat2
Z_OFFSET 6.512422
CONFIG 0.000000
PLDWEIGHT 13000.000000
Fairing_attached 1
missiontime 0.000000

it is not the same way Sputnik expressed it.
If I want to put the DeltaGlider IV on top of it for example, what do I modify?

---------- Post added at 02:24 AM ---------- Previous post was at 02:05 AM ----------

Ok I tried to modify the file, it works just fine for the launch, but when I separate the first stage, Orbiter pauses, the fist stage rocket disappears and the only thing I have is the DGIV and the second stage togheter (like it is supposed to be) but the DG's skin is different.
Then I separate the DG from the second stage and it creates a second DGIV at the exact same place than the first one... I don't get what is going on. It also does this with the default Delta 4 Heavy with the normal DG on it.

[sputnik]

Of course it's not the way I expressed it. That's not the Delta-IV Heavy from Velcro EELV's; you're using a different add-on.

[AlfalfaQc]

Oh... But I don't think there is a Delta-IV Heavy in the Velcro scenario. Does that mean it is impossible to change the payload on it, or can I download it somewhere.

[garyw]

It may be possible - which addon is it?

It LOOKS like the payload is controlled by these two lines:

PAYLOAD delta4/sat2
MESH delta4/sat2

I'm not sure what the first one requires but the second one is just a pointer to the MESH which'll be in the [orbiter]\meshes directory.

[PhantomCruiser]

There are these...

Velcro EELVs v1.02

Velcro EELVs v1.02

[garyw]

And there is this which I've not yet used but I believe comes with a GUI payload management tool ->

Delta IV Launch Vehicles 3.0

Delta IV Launch Vehicles 3.0

[sputnik]

I think the problem is that you're trying to launch an alternate-skin DG-IV, and that doesn't work too well. I don't know what add-on you're using, but it apparently, like the CVEL part of Velcro Rockets, carries the payload as a mesh, then creates an instance of it at separation. The problem comes if the add-on doesn't handle that sort of thing well, and DG-IV doesn't. It was designed to do many things, but the add-on maker can't test it for the thing he's never thought of, like what if some guy creates it at the business end of a launch vehicle.

Velcro Rockets handles this by adding an additional attachment-based payload system; you could try using that. The advantage there is the DG-IV is already created when the scenario starts; the scenario file can pass it all its parameters until it's happy, and THEN the launch vehicle grabs it and flings it into the sky. There are a bunch of other attachment options out there: Universal Cargo Deck, AttachmentMFD, any other Delta-IV add-on that does attachment (looks like Virii2k's will do that; I haven't tried it).

[AlfalfaQc]

I use the add-on that garyw proposed, but I'll try the one for velcro rocket, It will probably work

---------- Post added at 11:44 PM ---------- Previous post was at 04:50 PM ----------

Ok, I re-read the doc for Velcro rocket and I think I just understood something. I have to put the DG-IV as an attachment stage instead of using CVEL so it will create the payload at the start of the scenario instead of when it jettisons it.
The thing is, it looks very complicated for me. I'll try to figure out how it works but if someone has a better idea, just let me know.

Cheer
Alfalfa

Edit: I think I understand a bit more, I use the SERIESBURN command to put the deltaglider on top of the rocket, but the thing I don't get is where do I say what is the payload (or attachement) I use. Where do I say that it is the DG-IV?

Re-edit: I tried using the normal Deltaglider and I can make it work... for the first two stage... but when I jettison the DG, Orbiter crashes.

Here are the codes on the scn file
BEGIN_SHIPS
DGIV:Deltaglider
STATUS Landed Earth
BASE Cape Canaveral:6
HEADING 0.00
FUEL 1.000
END
DeltaStg2:Velcro/D4Stg2_5m
STATUS Landed Earth
BASE Cape Canaveral:6
HEADING 270.00
TGT_HEADING 095.0
FUEL 1.000
CONFIGURATION 0
SCREENHEIGHT 250.0
; PITCHMULTIPLE 0.25
CAMERA 0 0 20.0
Fairing 2 2.0 4.0 0.0 0.0
SERIESBURN 0 DGIV 0 0 -9.25 0 1 0
END

any idea?