quadrature-encoder-course/lessons/02-using-encoder-feedback/01-measuring-wheel-speed/measuring-wheel-speed.md

title	summary	chapter	order	tags	estimated_minutes
Measuring Wheel Speed	Convert encoder counts over time into rotational speed for a drive wheel.	Using Encoder Feedback	1	speed odometry robotics	9

Measuring Wheel Speed

Position counts become useful control signals once you add time.

To estimate wheel speed:

1. sample the encoder count at a fixed interval
2. subtract the previous count from the current count
3. divide by the sample period
4. convert counts per second into revolutions per second or wheel surface speed

Why this matters

Speed feedback is the bridge between open-loop motor commands and predictable robot motion.

If two drive motors get the same PWM value but spin at different speeds, your robot will drift. Encoder-based speed estimation lets you detect and correct that mismatch.

Checkpoint

Plot wheel speed over time while ramping the motor command up and down.