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Higher grade polynomial and law curve

Higher grade polynomial and law curve

Higher grade polynomial and law curve

(OP)
Hi everybody,

I'm curious if anybody can help me with the following problem.

I want to create a law curve or helix that is driven in the Zt direction by a 7th grade polynomial (in attached picture the zt is just defined to have a height of 50 mm).


The 7th grade polynomial looks like: -346440.03*t^7+704560.56*t^6-555866.89*t^5+214712.97*t^4-42523.485*t^3+4276.0711*t^2-320.74256*t+73.858905. When entering the polynomial for Zt, NX prompts an error

Does anybody know how to create this curve?

Next I want to cut out along this law curve, see 2nd picture where I used a constant pitch just to get an example.


Thanks in advance.

RE: Higher grade polynomial and law curve

Try putting the coefficients in parenthesis

Maybe it's confusing the system

RE: Higher grade polynomial and law curve

In the expressions dialog, the t parameter needs to be created as a number:constant type variable rather than a number:length type variable. As it is written now, the system is trying to add a value with mm^7 units with a value with mm^6 units (+ mm^5 + mm^4 etc) and it can't add them because the units do not match.

www.nxjournaling.com

RE: Higher grade polynomial and law curve

(OP)
Hi Cowski,

Thanks a lot, that little change in variable type worked fine. Now the helix follows nicely the higher order polynomial.

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