Hello, We all know speed is the first derivative of displacement... but here is what i want to know: I know displacement and time... how can i find speed. The reason is that i have 2 wheels operated by motors, and on the wheels I attached an encoder, which reads the rotation of the wheels... But because the motors tend to run at different speeds, which causes instability(i want both wheels to operate at the same rate.) So... I want to use the information feedbacked from Encoders to adjust the speed of these motors. How can I achieve that?