Convert first order transfer function to c code?

Question

I have a simple first order transfer such as "3/s+3" or "tf(3,[1 3])" function and I would like to implement in c code. I have a C function that is called with the delta time since the last iteration: double output(double input, double t); //usually, t is around 0.01 second How do implement the transfer function 3/s+3 in C?

Answer 1

To implement a first order transfer in C, you can use different methods. Let's use the Euler method for this specific example.

In C, you can use static variables, which retain their value between function invocations. This means the y_prev will always remember the previous y value.

double output(double input, double t) {

static double y_prev = 0.0

double K = 3.0;

double tau = 1.0 / 3.0;

// Discrete-time approximation using Euler method

double y = y_prev + (K * input * t) / (tau + t);

y_prev = y;

return y;

}