[Klaus] wanted some sort of aid for parking his car, and after running across a $4 ultrasonic sensor, decided to build his own speaking distance sensor (.de, Google Translation). Inside [Klaus ...

What’s the radar enthusiast to do? While it’s not radar, subbing in ultrasonic sensors is how [Dzl] built this sonar imaging system using a lot of radar principles. Initial experiments ...

Phones have mostly ditched curved edges due to user request, but the fingerprint reader under most screens is the new problem.