Nonlinear system identification - matlab

1. What is a nonlinear system model?
2. How do you linearize a nonlinear system in Matlab?
3. What is ARX in Matlab?
4. Why is system identification important?

What is a nonlinear system model?

In mathematics and science, a nonlinear system is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathematicians, and many other scientists because most systems are inherently nonlinear in nature.

How do you linearize a nonlinear system in Matlab?

Linearization is a linear approximation of a nonlinear system that is valid in a small region around an operating point. For example, suppose that the nonlinear function is y = x 2 . Linearizing this nonlinear function about the operating point x = 1, y = 1 results in a linear function y = 2 x − 1 .

What is ARX in Matlab?

The ARX model name stands for Autoregressive with Extra Input, because, unlike the AR model, the ARX model includes an input term. ARX is also known as Autoregressive with Exogenous Variables, where the exogenous variable is the input term.

Why is system identification important?

System identification requires that your data capture the important dynamics of your system. Good experimental design ensures that you measure the right variables with sufficient accuracy and duration to capture the dynamics you want to model.