non linearity of sensor

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Mat CR on 20 Nov 2019
Edited: Mat CR on 6 Dec 2019
hello there
i am investigating the effect that nonlinearity will have on my inertial sensors and i am having some problems constructing a code to show the effects, basically i am trying to generate a random non-linear sine wave which i then want to plot on top of my linear actual sine wave signal.
Daniel M on 20 Nov 2019
What do you mean by random non-linear sine wave?
A*sin(2*pi*B + C) + D
% A = amplitude (vertical elongation)
% B = frequency (horizontal elongation)
% C = phase shift (horizontal transformation)
% D = baseline (vertical transformation)
Which of A, B, C and/or D do you want to be random and nonlinear?
If you're not sure, perhaps a drawing would help.

Daniel M on 20 Nov 2019
Edited: Daniel M on 20 Nov 2019
In the figure I don't see a different value for B. I see a phase shift (C is close to but less than pi/4) and decreased amplitude (A ~ 0.8). If you are interested in a changing frequency , then I suggest you look into the chirp function.
Edit: sorry, I only saw part a. If you want something like part b, it looks like there is coupling of some higher frequency behaviour with the phase of the original signal. That is, when the signal is at a peak or trough, there is some jitter/noise. It's not straightforward how to represent this, but you could try adding another signal composed of various noise (rand or randn) and step functions.