Many dog breeds require a lot of exercise and mental stimulation to be healthy and happy, but not many of us want to spend our time endlessly throwing a tennis ball. That’s why Connor Benson used an Arduino Nano to build an automatic ball launcher that is capable of keeping his pup entertained all day long.

In this case, the Nano is being employed to sense when a ball has been dropped into the ball launcher, spin up the launcher’s motors, and then release the ball down into the spinning wheels. The board requires very little power, so this machine can run on a battery pack for a relatively long time.

The frame and mechanical components are 3D-printed in a nice bright blue color. An Adafruit proximity sensor is implemented to detect when a ball is in the machine and then releases the ball with a hobby servo motor. The 3D-printed wheels that grip the ball and fling it out are spun using powerful brushless DC motors. The Nano drives those via electronic speed controllers (ESCs).

Now Benson can play fetch with his dog for hours at a time without tiring out his arm and the dog certainly seems happy with the project.