topic Re: Reuleaux triangle in LabVIEW

Reuleaux triangle

DavideB — Wed, 01 Oct 2014 08:04:52 GMT

Dear forum experts,

I have to draw a Reuleaux triangle (non-obvious constant width curve) using Labview, like the one in the attached somatochart file.

The program will be used in an anthropometry laboratory to indentify the somatotype (endomorph, ectomorph or mesomorph) of individuals.

Can you give mer any suggestions?

Thanks,

Davide

Re: Reuleaux triangle

GerdW — Wed, 01 Oct 2014 08:38:49 GMT

Hi Davide,

use a XY graph and draw your curve.

What exactly is the problem?

Re: Reuleaux triangle

DavideB — Wed, 01 Oct 2014 09:13:59 GMT

Dear Gerd,

I understand I am missing something... but the triangle is an area, not a function. The total area is 0.5(pi-sqrt(3))R^2.

R is the constant radius of the three intersecting circles.

Actually, I have no clue where to begin from...

Thanks,

Davide

Re: Reuleaux triangle

GerdW — Wed, 01 Oct 2014 09:20:59 GMT

Hi Davide,

you need to know the inner triangle. Once you know its corner points you can draw arcs (or better: calculate XY points for a plot). It looks like simple geometry math!

Now I looked at Wikipedia and I can also suggest to use a 2d picture indicator for your Releaux triangle plot. Here you could use draw functions directly instead of calculating points in a XY graph…

Re: Reuleaux triangle

DavideB — Wed, 01 Oct 2014 09:24:49 GMT

Thanks Gerd,

the inner triangle is equilateral, the side being R.

What is a 2d picture indicator?

Thanks

Davide

Re: Reuleaux triangle

GerdW — Sun, 04 May 2025 22:59:37 GMT

Hi Davide,

apply some basic math to calc the corner coordinates from your R value…

The 2D picture indicator is explained in the LabVIEW help!