The $50 sensor runs on two coin cell batteries so you don’t need a nearby power source for installation.

Tests confirm graphene-based energy harvesters can use ambient energy to run ultra-low power sensors — the first hurdle in developing autonomous sensor systems.

This project involves using an Arduino to measure distances using an ultrasonic sensor and controlling a buzzer and LED based on the measured distance. The provided Arduino code performs the following ...

The news you need to know today — and the stories that will stick with you tomorrow. Plus, special series and behind-the-scenes extras from Here & Now hosts Robin Young and Scott Tong with help from ...