creating aircraft fuselage

[rcnicke]

I've been trying to create an a320 fuselage, but can't seem to get it right.

I've sketched a side view of the fuselage, and a front view of th section (a circle). Now I'd like to kind of extrude or loft the circle "inside" the side view sketch, so it becomes a solid fuselage. But I'm really bad at it, and have no idea of how to do it. Can anyone help me out on this one?

[DareBee]

This would take awhile to explain, but you aren't very close to getting this to work.
I suggest you go and do the tutorial provided with SW on lofts and then post any new questions you may have.

[Sanghera]

Try extruding the two side views then intersect them where they line up in 3d space. Not sure if this works in Solidworks done it in others. Just an idea, not sure if it would work.

[scottsss]

What version of SolidWorks? I have 2003-2004. So if your working in those versions you can post the file and I'll take a look.

[nervis1]

Darbee, on the money. You will have to sketch the profile of the body all along it's length, then loft through all of the profiles.

Think of it like building one of those old balsa RC planes, with the ribs of the fuselage, then you skin it with the loft. You can add control curves if you need to as well.

The software has a tutorial with it in the help files on lofting.

[rcnicke]

Hello!

Thanks for the replies and suggestions.
I have done the tutorial of course and did some reading in the documentation, but i'm still having problems getting the guide curves right.

The "ribs in balsa plae" approach is a good one, but that means a lot of ribs (a lot of planes!), when i actually only need one shape. I'll keep trying...

[nervis1]

You only need one profile but in 3d the fuselage shape is almost constantly changing as you move front to back. You will need that info in your model if you want to do it right.

If all you need is a rough estimation of an aircraft body then just draw the profile, extrude it and put big fillets on all the edges to round it all out.

Did you do the online tutorial on lofts? Thats pretty much all you need to know.

It will take a long time, what you are trying to do...well guys at Lockeed and boeing get paid big bucks to do it.

[JerryFlyGuy]

Making a Fuse in SolidWorks isn't to hard, it just takes dedication to doing it correctly. The best way I've found to do it is in conjuction with a form of mechanical [ the same way it was done when hand drawn] conic's. It's nearly impossible to describe via a forum board. An A320 fuselage should be pretty easy to do, I wouldn't use the top/side views for anything but refrence. Primarily most of my modeling of this type is done via stations down the length of the fuse. I constrain the station profiles to the top/side profiles via contruction lines [ make sure you side/top profiles are fully constrained]

The basic's for making the 320 fuse would be as follows [ at least how I'd do it] Get your constrained top/side profiles, start w/ a station at the location where the fuse becomes constant in shape [maybe 15% back from nose], extrude that shape back to the point where the fuse starts to taper in again [ disregard the wing fillet location and shape for now]. Creat maybe two stations for the nose section [ you may need more to get the front windows to look correct.. I'm trying to remember what they look like..] Do a loft from about 3% back to the extruded section with a "normal to" end condition. Do the same at the tail and then finish the nose off w/ a "dome" function. This should get you pretty close to what you want, you then put in the airfoil station where the fillet ends and is blended into the wing, you put a 3d sketch onto the side of the fuse, or just use a projected split line to split the skin of the fuse in a shape that matches the fillet profile on the side of the fuse. Convert that split line into a 3d sketch and loft that into the previously created airfoil shape. You may need to add guide curves to get the proper shape. This may also require some clean up "fillets" to get blended lines. I find that at this point, instead of doing the same on the other side I like to do an extruded cut and litterally cut the fuse in half [ remove 1 complete half] then do a body mirror with merge and you'll have a perfectly sym model.
thats a short version of how to do it, Attached is a model I did on my own design for an airplane.. it took some time and I used the conic's style driven model I wrote about above, its an alot more complex way of doing things but I like the results. PLUS... the major advantage is that I have a non constrained spline control line, which by simply opening that sketch and draging the spline, I can change the curvature of the fuse stations from a very square look [ looking from the nose aft] to a perfectly circular or even hyperbolic [ or is that parabolic] profile. All by dragging 1 spline. This spline drives several [ over 80.. I checked] formula's and smooths things out b-e-a-u-t-i-f-u-l-l-y.. Like I said.. it took a while to set up but it was well worth the time.. Here's a sample of what it will produce...


JerryFlyGuy

[Inventthis]

Hey JerryFlyGuy, are you thinking about building the canard aiplane?
Could you post the SW file?
Thanks

[rcnicke]

Very good reply, thank you!

[JerryFlyGuy]

Originally Posted by Inventthis Hey JerryFlyGuy, are you thinking about building the canard aiplane? Could you post the SW file?

Inventthis, Well I actually do plan to build it, I was at the point of ordering all the laser cut parts to build buck's for it and then got the CNC bug again. I started doing some looking around the web, came across this site and realised that hobby level cnc has come a long way since my last look. I'm currently building a 20 x 10 x5 router for cutting the buck's and molds for this a/c. I plan to start w/ a 1/4 scale R/c model and get the aerodynamic's down and then build the full size a/c. As far as posting the file, well.. since I spent as much time as I did getting things where they are.. and my financial future may be based on this design.. it might be best for me to hang onto this for now.. thanks for the request though..

JerryFlyGuy

[Scoobyvroom]

Jerry Fly Guy

Very nice looking airplane. I have come very far learning SW and have created some very basic airplanes, fuselage, tailplanes and all the rest. Like Inventhis I would really enjoy looking at the SW file just to see what is takes to make a nice smooth fuselage. I was able to follow your instructions here but I am more of a hands on guy, where I like to take things apart to see how it all works.

Thanks alot,
Chris