Estes Alien Invader nosecone for Rocksim?

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Bill S

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Anyone ever come up with an nosecone for an Estes Alien Invader, the one with two elliptical bulges, one on each side?

I'm looking to make an Rocksim file for the Estes Protostar, and it would be really handy.
 
IIRC, I did it for the 4x upscale. I'll try to remember to look when I can get to my dropbox.
 
I looked at the file, and it has an ordinary nose cone, not the one with the bulges on it. I suspect it'll be very hard or impossible to make such an nosecone in Rocksim.
 
It may or may not be possible to finagle something that *looks* kind of like it, but it is unlikely to give accurate simulation results.

I just knocked this together in an unreleased alpha of OpenRocket:
1588620621046.png

Looks decent (not perfect, but decent). Likely to produce very wrong sim results.
 
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I did a quick and dirty nosecone up in Rocksim, using 2 pods (1 each side) with 2 transitions on each pod. Hopefully the simulation will take them into account.
Lost all the work though, as I saved it as a custom nosecone in the database, and the pods and transitions didn't save. Have to redo them.Protostar side pod rocksim mockup.png
 
Hopefully the simulation will take them into account.
It will, but it will likely be wildly inaccurate, because the program doesn't understand the finished geometry of the structure with all the overlapping objects. It is not a CAD program.

You'll probably get better simulations if you approximate it with structures that the program *does* understand, such as something like this:
1588682007753.png
That's a nose cone followed by 3 transitions. The exact geometry of the bulbous part is a wild guess; can't do much better than that without getting a wind tunnel or CFD analysis of the original cone. I'm thinking I made it a little too big there.

Bottom line: if you want something that'll *look* good, you can do it in a way that you were doing it up there in your last post. If you want it to *simulate* properly, you'll have to take a guess at an approximation using components that the program can simulate more accurately.
 
I can see why nobody has done a Rocksim file for the Protostar then, as this is getting to be more complicated than I'd like to mess with. Oh well, it was enlightening anyways. :)
 
I did a quick and dirty nosecone up in Rocksim, using 2 pods (1 each side) with 2 transitions on each pod. Hopefully the simulation will take them into account.
Lost all the work though, as I saved it as a custom nosecone in the database, and the pods and transitions didn't save. Have to redo them.View attachment 415166
this is what I thought I had in the link I sent. I probably only did it in the upscale. I completely forgot to look last night...
 
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