With a standard old HC-SR04 ultrasonic sensor, an audio module and a servo to drive a custom gauge ... for anyone who has a bunch of these little Arduino-compatible modules lying around and ...

A DIY The Wrench maker has built a smart desk dustbin with an automatic iris-style lid, adding both functionality and a ...

To that end, it uses an Arduino Nano armed with an ultrasonic distance sensor to detect when mice have entered a plastic container. The container’s hinged door is is held open with a servo.