How to measure velocity of an object using IR sensors?

Do you know that you can use the IR sensors in your robotic kit for innumerable different applications? One interesting application “How to measure velocity of an object using IR sensors?” given below will help you understand it.

Velocity measurement system

In this system use two IR sensors, kept on a table, separated by a distance of 1m exact. Then roll a ball in front of first IR sensor. Write your code, such that when the ball passes in front of this first sensor, a counter is triggered in the program.

Now when the ball passes over the second IR sensor, the counter should stop. In this way, the counter will count between the position of ball from one sensor to another.

Now using the mathematical calculations, you can calculate the velocity of the ball passing in front of IR sensor-1 and then in front of IR sensor-2 by using simple formula: velocity = distance/time.

Precautions: Please note that this application is useful only for slow motion of the objects moving in front of the IR sensors. For very fast moving objects, above the velocity/speed of about 20km/sec, the IR sensors are NOT SUITABLE. This is because, the sensors are rather slow in their response.