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So you like to race, but you don’t trust the person in charge of timing? If so, this should be next on your “things to build” list. It’s a digital timer made out of an Arduino, some 595 shift registers, and a few 7-segment displays. Not too bad for the makers first Arduino project!

The project is an IR beam to trigger the timer and can be used on tracks (since the same beam is used for starting and stopping the timer. The purpose is to offer accurate lap times so their cannot be any debate on the hand clocked times wich quitte often occur.

Read more about Time sensor using IR beam and Arduino