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 ...

The IR Detector proximity sensor is designed to be compatible with both Arduino and Raspberry Pi platforms, making it a versatile choice for hobbyists and professionals alike.

An Arduino Mega Pro Mini handles the logic, sending PWM signals to a DIY servo. The chassis consists of a modified Crazy Cart, selected for its absurdly tight turning radius.

Here is an ultra simple Arduino Night Alarm project wired around a handful of inexpensive and easily available components. One advantage of using Arduino as a security system is the flexibility!