Potentiometer vs. Encoder

[lokeshv]

Originally Posted by Mr V

It depends on what you want the sensor to tell you.

As you noted a potentiometer will give you an absolute position within a limited range of motion. So for example connected to an "arm" it can tell you exactly where it is within its range of motion regardless of its starting location.

An encoder can tell you the rpm of a shaft or be used on a device with unlimited rotation to move a certain number of steps relative to where you start counting. It can be useful in autonomous to have your robot move a specific distance from its starting position or to maintain a set rpm with a varying load.

what is calculation to find speed with help of encoder.....