Generating a surface from polylines

Rhino
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1

Hello everyone,

I am a student working on a generating a surface so I can conduct CFD analysis later in Ansys, I used a Renishaw scanner to scan a BMW model and have been battling to generate a loft or surface of a solid body from the scan. I have attached a copy of the file and a video showing the outcome when I try to generate a solid surface from the polylines. For context I would like it to look something like this:

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So I can then export the file as a Parasolid and Conduct CFD and further improvements on the body of the car. Would you be able to provide any help as this is a problem I have been battling for a long time and have done extensive research both online and alongside my lecturers in university with. If anyone can help it would be really appreciated.

Kind regards,

Ahern

beemerRHSAAFCS.3dm (725.9 KB)

2

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You can divide the polylines and shrinkwrap the points into a thickened mesh. Then QuadRemesh. If you moved the geometry to be symmetrical on x or y, the result can be symmetrical. The result is a mesh or SubD and the SubD can be converted into nurbs.

3

Oh WOW!!! I spent a ridiculous amount of time trying all sorts of tutorials and videos online, I am going to try that and see how it works out. Thank you soo much!!

1 Like
4

  1. Move the curves to the X axis using the gumball

  2. Run _Divide to create a ton of points. 100 should work

  3. _Shrinkwrap with these settings:

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  4. _Quadremesh like this…

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5

Im currently getting something that looks like this. I’m really not sure where I seem to be going wrong. Would you be able to further explain the process possibly - sorry for all the hassle

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6

Did you divide the curves?

It should look about like this:

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You could also delete points going from one side to the other at the back edge of the front wheels and front edge of the rear wheels…

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7

I believe I did divide the curves as recommended, here is what my model look like after each step

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seems to be coming upside down next… Do you know how to fix this, surely something minor?

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Sorry forgot to attach how it looks upside down… has to be something minor surely? Should hopefully be the last hurdle to overcome

Thanks again

9

You mirrored in the wrong plane…

Set the CPlane to world and then in the QuadRemesh command mirror along X

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I think I would continue by deleting a loop and get rid of the inner part. Then drag and crease or add detail.

11

To drag parts of the ‘surface’ you need to run _QuadRemesh first

12

Hi everyone,

Just to give some background, I am trying to close up the front grill area and make it a solid so when I conduct CFD air will flow above and over instead of through the car. Does anyone know how to do this? I tried following

Scaled M3.3dm (9.2 MB)

the steps from above but didn’t manage. Also on another note would anyone know how to close the bottom of the car as I am trying to CNC the model from a block of wax material using a 3 axis CNC machine also? Thanks you

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13

There simply is no “make a car from some curves” button. You need to be an expert-level NURBS modeler.

14

Would you know anyone that might be able to help? Ive been battling rhino the last while and really need to make some progress on this project. I want to essentially close up the front, make a surface from the polylines and then export it as a parasolid or stepfile into powermill so I can CNC it. Would you have any help or advice? Would be really appreciated. Thanks

15

Generating surface or body from polylines - Rhino - McNeel Forum

Duplicate topics, please someone merge this and delete my post.