Lifting body


#1

Hi there,

I want to draw a 3D lifting body (essentially a triangularly shaped aircraft made out of an airfoil, https://en.wikipedia.org/wiki/Lifting_body) but I’m very new to SU so I need some feedback on which of the two below ideas is best, unless none is good and you have another one!

  1. Use a 2D airfoil to create a 3D rectangular wing and then somehow “cut/shape” it into a lifting body.
  2. Create a 3D triangle and then use the 2D airfoil to somehow “sculpture/extract” a lifting body

Of course I’m not asking for step-by-step instructions, just some tutorials/examples (preferably videos) that would help me with the basic functions that would be needed to do this.

Thanks for your time and support!!


#2

Neither of those options would be particularly efficient. The best thing is to start using plugins right from the get go for these types of things. To do that you should look at using SketchUp Make 2017 rather than the web version: https://www.sketchup.com/download/all

You want either Vertex tools and SubD or Vertex Tools and Artisan Toolset. You can create a basic mesh and then use subdivision to smooth it out. I will find a good tutorial and post it back on here later for you if nobody beats me too it.

You can also model from blueprints, there are plenty online for various USAF and NASA lifting bodies. You simply follow this tutorial but apply the subject to whatever you need rather than a car: https://www.youtube.com/watch?v=5116hUlem_8


#3

Hi, I’m new to SU and would like to know more about " Vertex tools and SubD" and “Vertex Tools and Artisan Toolset”; are these extensions I can download? I’m also trying to make a wing airfoil that I can apply the “Push/Pull” and “Scale” tools to make a wing out of after lining-up the airfoil (as cross-sections). Thanks.


#4

If you Google them you will find a wealth of information and tutorials on you tube and Sketchucation.com

More so than I can sum up for you.


#5

Thanks a lot for the help and sorry for the late follow up.

I didn’t download the tools you describe because I found this simple video https://www.youtube.com/watch?v=7vH8BSCaS5M&t=160s and it seems I can use it to do what I want but I have a problem.

In the tutorial, he starts creating the fuselage with an arc but my shape is much more complicated so I created it with two Bezier curves. I can pull the initial fuselage surface that I create but when I snap it on the next surface, the surface “splits” and I cannot use the Scale tool on the entire surface because it’s made of the two Bezier curves.

Is there a way to somehow combine the two Bezier curves so that that I can do what the tutorial shows that can be done with arcs?

Thanks again for the help!!


#6

Can you post a screenshot so I can see?

There should be no reason why you can’t manipulate a face made from more than one curve.

Cheers


#7

Thanks for the quick reply!

Attached is a screenshot, as you can see the surface is split in three areas and I have selected one of them with the Scale tool. You can also see the line that is created by connecting the two Bezier curves on the side of the pulled surface


#8

You are likely to receive even more support if you post the actual skp file. I also agree with @liamk887 in that plugins will be more useful in your quest to create a lifting body. You cannot use plugins with the web based versions of SketchUp so SU Make 2017 should be d/l’d from the link he provided earlier.


#9

I used the tutorial with the bezier curves because it seems fast/simple, if ti doesn’t work out I’ll certainly check the suggested plugins.

skp file attached but pls note that I used a rather crude way to do what the tutorial does, I pulled each surface 10mm short of the next surface and created the attached… any suggestion to make it better?

Sorry, I’m finishing a new one, I’ll upload when ready…


#10

On your screenshot it looks like you could delete the corners of the rectangle and add the unselected arc segments to your selection (shift select). Then the scale method could maybe work again.

When geometry intersects in an unwanted way (or has small holes or does not fit together), you better go a step back and figure out how to do it again more properly instead of doing tedious cleanup.

If the rectangle is only “helper geometry” you could have grouped it to prevent intersection with the actual geometry you want to draw.


#11

thanks, grouping the “helper geometry” sounds good I’ll try it!


#12

I will wait until the file is ready