Put aside all of the projects that use an Arduino to blink a few LEDs or drive one servo motor. [IngGaro]’s latest project uses the full range of features available in this versatile microcon… ...

The security system comprises of an Arduino Uno microcontroller and a standard SIM900A based GSM/GPRS modem. The whole system can be powered from any 12VDC/2A power supply unit/battery. Advertisement.

If you are interested in reading more about laser tripwire security systems, check out this similar passcode-based system, this alarm system built into a toy, and this Arduino-based alarm system.

That’s when I saw several instructables (Laser Tripwire Alarm, Arduino – Laser Tripwire Alarm System, and Super Easy Laser Tripwire, among others) using a laser tripwire.

A laser manufactured by the German company Sick, sold by Comtrol Corp., in the United States, uses 905 nm — slightly higher than the 850 nm commonly used in fiber optic systems.