PID Controller Guide

Proportional – your error, the value between where it is now and where it should be.

error = (target value) – (sensor reading)

Integral – the running sum of previous errors, used for making fine movements when the error is small.

integral = integral + error*dT

Derivative – the change in errors, used to predict what the next error might be.

derivative = ( (current error) – (previous error) ) / dT

The loop – the calculations all need to be run inside a loop – don’t forget to include it!

Put the three components together, plus some accurate values for Kp, Ki and Kd, and you will have a very consistent and accurate controller.

Download:
PID Controller Guide.pdf (141.0 KB)

Excellent summarization of PID Controls
Kudos to who wrote it up

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