Thanks. It is C++ code using Armadillo for linear algebra and BLAS/LAPACK subroutines. Source code is a bit messy, but will try to clean it up and put it on a different repo when I find the time.

The most complex part is the identification algorithm, which uses this algorithm: https://math.stackexchange.com/questions/1428566/fit-sum-of-...

Oh, awesome! I’ve got to do some pid tuning this week. I’ll definitely be interested in the raw C code.

I wonder if it could be portable to a microcontroller Are the blas routines expensive or large matrices?

The code is C++ code, It could be ported to an MCU if there is a fairly recent C* compiler (C11+). But the algorithms are quite expensive, there are multiple matrix inversions, the size of the matrices been as large as the data you put in into the tool. typically between 500 and 10000 data points.