STEM PROJECT- Motion sensor and raspberry pie?

i’m working on a STEM project. I’m working on making a soccer goal that detects the velocity of the soccer ball i was wondering what products i should purchase, I’m thinking i need a motion sensor and a raspberry pie but i’m not really sure.

If i could have some help on what i need then that would be greatly appreciated.

Thanks, Robbie

Hi Robbie,

Will you need to be able to measure the speed of the ball no matter where it enters the goal? I can think of a way to do it if the ball is always on the ground, but once its in the air I’m not sure.

yes we can do it when it is only on the ground.


I think that you might be able to do it with a break beam sensor. An ultrasonic sensor would not be able to take readings fast enough to detect a soccer ball moving past. If you put one laser break beam sensor (think Mission Impossible) in the front of the goal, and one in the back, you could use an Arduino or Raspberry Pi count the time between the ball crossing the front sensor and the back of the goal sensor.

This obviously wouldn’t work for a ball flying through the air though. The way I see it, you have two routes to take if you decide to go with this method. Method 1 includes actual laser break beam sensors, these are modulated and can work in sunlight:

Method 2 is that you make your own. This wouldn’t have nearly the accuracy, but if you mounted a light sensor in the bottom of a pipe, so little light made it down to the bottom, and then point a regular laser across the goal and down the pipe to strike the light sensor, you would be able to measure the substantial drop in light when the beam was broken. Putting it inside a shroud or pipe would reduce the effect of sunshine.

Hopefully that gets you started!