[Feature request] Ability to fuse nose cones-to-transitions and transitions-to-transitions

[hcraigmiller]

Rocket designs have and more frequently are using non traditional nose cone and transition profiles, and there are already two other current issues relating to this. Issue #327 requesting the ability to add spherical tips to “blunt” a nose cone and Issue #1218 requesting the ability to make freeform nose cones. This approach will resolve both.

The simplest example to start with is fusing a spherical tip to a conical transition to make the aluminum tip that is used for almost all rockets using motor class above “I.”

Fuse.Nose Cone 2 Transition.ork.txt

Another nose cone example is the Estes Mars Lander nose cone, a fusing of a nose cone to three transitions.

Fuse.Mars Lander.Nose Cone 2 Transition 2 Transition.ork.txt

And, transitions more commonly have more than one angle as well.

Fuse.Transition 2 Transition.ork.txt

Approach:

1. Warn the user that fusing cannot be completely undone.
2. Only fuse contiguous nose cone and/or transition components.
3. Before fusing, change the position reference of all other affected elements to “tip of the nose cone,” move these elements to the lowest component to be fused, and change the position reference to the “bottom of the parent” component.
4. Change the shoulder diameter, length, and thickness of component faces to be fused to zero.
5. For all other settings (except remaining shoulder settings), change the lower component characteristics to match the top component characteristics.
6. Grey out the general parameters that no longer apply, essentially everything except wall thickness (and filled), component material, and component finish.
7. When a change is made to the fused component (the top component), that change should also be made to all fused components; those changes will be needed to un-fuse the components.
8. The mass, CG, and CP calculations will need to be an aggregate of all fused components.

The tree will need to be changed to remove the indication that the fused components are individual components (maybe something like this).

If unfused, all other affected elements will be a subcomponent of the lowest unfused component and remain referenced to the “bottom of the parent” component and fused mass, CG, and CP overrides will be removed (this is why the warning is given, the other affected elements cannot be returned to the component under which a particular element originally resided), and all other characteristics will remain the same as when fused.

Questionable area: What to do with decals.

[neilweinstock]

I think, rather than "fusing", this would be a perfect application for subassemblies. I'm not sure that a permanent "fusing" adds any value. If the handling of subassemblies is smart and sensible, then you should be able to do most or all things with them that you could do with a fused component. I think.

The decal question is.... a good one. :) I can't think of any reasonable way to do it. With a subassembly, you could partition the decal and apply each piece to each subcomponent... but that would be a nightmare.