circuito.io is back with another simple to make but still very interesting maker project: an air gate made out of an Arduino.

In this context an air gate is a type of sensor which gives a pilot an indicator when their drone has passed it. In drone racing this can be used as checkpoints, at finishing lines and to chart out a course.

The aim of this project was to make a smaller, DIY version of the gates which can be used in doors for the smaller multicopters.

To do this they paired an Arduino Pro Mini with an ultrasonic sensor and an LED. When a drone (or anything else, for that matter) gets close enough the LED switches from red to green, indicating a successful pass.

Once completed the electronics are put inside of a rather attractive, 3D printed housing.

You can find a full guide to replicate this project, including code and STL files, over on hackster.io.

While this is intended as a practice tool for racing specifically, we can think of a few upgrades to expand it. Adding in some timing and a buzzer and it could be used to have drone races right on your desk.

You could even add RFID chips to multiple drones and scanners in the gates so the race can be tracked automatically.