Attachment vs. Docking Question

[Bullethead]

I'm trying to figure out how to use this attachment vs. docking thing I keep hearing about, with no luck :sos: For instance, I'd like to try to put a space station together using Greg Burch's SSBB lego system, using one of his Descartes-class ships. But the docks with those add-ons seem to assume I know the basics of the underlying system this is all built on. Problem is, I don't, and I can't find the info elsewhere. So can somebody throw me some hints, please?

 

[Zatnikitelman]

I'm not exactly sure what you mean. When two free docking ports are close enough to each other (0.3m I think), they automatically dock together unless one of the vessels is a child attachment of something else. Attachments are a sort of override as their position is entirely dependent on whatever they're parent vessel is. The best example is a robotic arm. The child vessel is the object grappled by the arm. In Orbiter atleast, this child vessel is dependent only on the position of the parent (robotic arm) vessel for position information. There are some exceptions, but these are custom addons.
Attachments usually have to be defined in the scenario file unless an addon or a separate system of sorts tells the attachment points to attach. I know it's a bit confuzling, but once you've played with it a while, you'll get the hang of it.

 

[n0mad23]

I found the documentation from Vinka's Spacecraft to be very useful here. That in conjunction with opening and studying the .cfg, .ini, and .scn files.

I'm relying on memory here, but it seems like Greg Burch's add-ons rely on Vinka's Spacecraft(#).dll's so the information will translate nicely.

 

[computerex]

Docks and attachments are defined inside the configuration file of a given vessel, or they can be created inside a specific vessel module. Attachments are a simplified version of docking. The physics are simplified. Vessels in Orbiter can't be in a landed state while docked, that's why attachments are there so it's possible to take payloads in Orbit. Dockings are automatic, however attachments are only operated via API calls.

 

[NukeET]

For instance, I'd like to try to put a space station together using Greg Burch's SSBB lego system, using one of his Descartes-class ships.

Runs in my mind that in the documentation for GregBurch's Descartes class vessels, he describes rather well how the attachment points work.

This is one of those threads lost when M6 didn't want to play nicely anymore.:shout:

 

[Bullethead]

Thanks for the help, everybody.

This is one of those threads lost when M6 didn't want to play nicely anymore.:shout:

It might be a good idea for somebody to post up some summaries or how-tos on a variety of topics like this, for the benefit of those of us who never got a chance to read M6. There's apparently a vast amount of info out there, that's become part of the community general knowledge, but which is devilishly hard to find if you're new to the community. I can think of a few such things off the top of my head, such as:

• Scenario/config file text editing: why you need to do it, what you change, and what it does for you.
• Vinka's DLLs: Where to put them, what they do, and how to use them.
• IMFD: What all the buttons and options do that aren't covered in the available docs, and why you'd want to use them.

Now, back on topic:

On this particular subject of attaching stuff, let me see if I've got this straight. I'm just trying to get the general concept down here, and will worry about the details later. So as I understand what you all have said, it goes kinda like this (assuming building a station in LEO using parts fabricated on Earth):

1. Design the station so that you know what parts you need and what order to add them to the growing structure.
2. Save a scenario out of Orbiter that approximates your starting condition, such as having the transport ship sitting at your launch facility.
3. Use a text editor on 1 or more of the scenario files (don't know which files or what to do to them) to "attach" the 1st batch of station parts to the transport ship.
4. Fly up to where you want to build the station and "detach" the 1st part from the transport ship, using whatever ship-specific command does that.
5. Detach the 2nd part from the transport ship and use the ship's RMS or a tugboat to move the 2nd part into contact with the 1st part.
6. Dock or "attach" (I'm not sure which) the 2nd part to the 1st part.
7. I get the impression that each part is like a separate ship, which you can enter with F3. Do so to turn on whatever bells and whistles the parts have. Being inside the parts might also be necessary to dock and/or attach them, but I'm not sure.
8. Repeat steps 5-7 until you run out of parts, then go land back at base.
9. Save the scenario, which now includes your partially built station.
10. Edit this new scenario to load your transport ship with the 2nd batch parts and reposition the ship for take-off.
11. Repeat steps 4-9 until the station is finished.

Is that about right?

 

[Bullethead]

On a related issue to this whole attachment thing...

As I understand from what you all have told me and Burch's docs, Orbiter only takes the mass of attached parts into account if they're directly attached to the ship. So if you have it set up so you've got further parts attached to only each other, and only 1 of which is attached to the ship, then the mass of all the others is ignored. Is that right?

OK, now I see over at Orbit Hangar there's a thing called "Attachment MFD". From what I can determine, this appears to be intended to overcome this problem and make all the masses count, regardless of what they're attached to. Is that right? And if so, is it worth doing?

Thanks.