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Law defined spline (Law Curve) NX12

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SiW979

Mechanical
Joined
Nov 16, 2007
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804
Location
GB
Hi All

Would anyone be able to help me with the expressions I would need to define a law curve with the same form (size not that important) as the attached example please?

Many thanks in advance.

Best regards

Si

NX7.5 NX8.5 NX9 NX10 NX11 NX12

Technical Manager

One PLM Ltd. (Formerly Majenta and Cutting Edge Solutions)
 
 https://files.engineering.com/getfile.aspx?folder=6831067b-784c-4139-9067-1dc007371869&file=law_curve.prt
I can't open the file, I'm on NX11. Can you post an NX11 version or maybe just a picture?
 
No, i do not have a solution, but i have a screenshot :-)

I highlighted the spline part of the entire composite curve, i imagine that Simon wants the entire 360 degrees as a single law curve.
image_wy4nvw.png


Regards,
Tomas
 
Okay, so here is a part that mimics the picture. The formula for zt isn't particularly elegant but does give a somewhat decent result.

The basic format for ZT = if((t*360)<260)(0)else(formula for the squiggly bit)
 
 https://files.engineering.com/getfile.aspx?folder=8fff2084-5997-4397-baf8-a1f74c955a3a&file=law_curve.prt
HI mmauldin

Thanks for the examples, I'm struggling to see how to get the Zt to alter in the second example, what do you need to change edit the amplitude as the wave in the law curve sketch is defined by p10? What does that huge expression for zt actually control and how do you make it take affect?

Best regards

Si

NX7.5 NX8.5 NX9 NX10 NX11 NX12

Technical Manager

One PLM Ltd. (Formerly Majenta and Cutting Edge Solutions)
 
In the second example , the expression Zt isn't used at all. ( probably left from example 1)
The Z-function of the law curve is entirely driven by the sketch, change the sketch parameters and the law curve will update.

Regards,
Tomas



 
Thanks Tomas, makes sense :)

Best regards

Si

NX7.5 NX8.5 NX9 NX10 NX11 NX12

Technical Manager

One PLM Ltd. (Formerly Majenta and Cutting Edge Solutions)
 
Yes, that last example was thrown together to show that you can control "z" by sketching any shape you wish. Might be easier than trying to generate a mathematical formula for your profile. You could even combine bridge curves with the sketch to create a pseudo "sine" curve.
 
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