I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. After some searching, I ended up using a microcontroller and a piece ...

To measure wind speed and direction, most people turn the traditional cup anemometer and wind vane. Another less-known method is to use an array of ultrasonic transducers, which doesn’t need any ...

This project is a simple modification of the LightGauge project. Instead of measuring light, we measure the ambient voltage field on pin A5 and use it to detect if someone is too close to our Arduino.

Here is a simple general-purpose security alarm circuit built on the Arduino platform. It brings up an obtrusive alert signal when an intrusion/theft attempt is observed by its front-end sensor. In ...