Non Linear sensor (pressure transmitter)

[krugdu]

How are others dealing with non-linear sensors? Rather than using the MAP node I generated a polynomial equation that followed the non linear data points. It looks like the following:

I only used the 2rd order in this example. The one i did before used the 3rd order, that’s the reason for the extra nodes that aren’t being used. I was able to match the gauge reading within 2psi from 10psi to 90 psi. Is this the way you would do it? Am I going about this the hard way? I was happy with the results. Is there a node for entering equations that are more complex?

[nkrkv]

Hello, you do it right. If you’re asking about entering formulas in Excel-style, there’s no such thing in XOD.

However, if you often need the polynomial function (OUT = b + a1×x + a2×x² + a3×x³ + a4×x⁴ + …) you might pack it into a re-usable variadic node. Something like:

Then you can use it, expanding to whatever order you like. Sixth for example:

Note, k and k+1 are utility pins in this case to make the variadic cascade work.

[krugdu]

That’s awesome! Thanks