Measuring air flow in an ... like with this ultrasonic flow meter, could be a big deal for DIY projects and the trades in general. The principle behind the sensor [ItMightBeWorse] is working ...

Inside [Klaus]’ device is an Arduino Uno, an HC-SR04 ultrasonic distance sensor, and an Adafruit Wave Shield. Originally, this parking/distance sensor used a small TFT to display the distance to ...