laser tripwire that sends sms

I am looking on building a laser trip wire that sends a sms only when the laser contact is broken, is this possible? what will I need and if anyone could help with the code?

You can get laser modules which have a (yellow) "enable" wire, allowing you to modulate it at - say - 38 kHz to operate with an IR remote sensor chip and reject ambient light and attempted spoofing.

You will need the laser, the sensor, an Arduino (UNO should do) and a GSM module. There are sketches around and libraries - as I believe - for the GSM.

The laser tripwire part is easy, the sms part is potentially harder. Not having done it, I imagine you have 3 choices to send a sms, and other possibility that might solve your problem:

  • Use a wired ethernet connection that connects to an internet service like ifttt (If This Then That: https://ifttt.com/wtf) to send the sms. You need an ethernet router nearby to plug the Arduino into.
  • Use a wifi radio internet connection that connects to an internet service like ifttt to send the sms. You need a wifi router nearby to connect to that will allow the Arduino to connect to it.
  • Use a GSM shield to send a sms (http://arduino.cc/en/Main/ArduinoGSMShield). This requires you to use a cell phone plan that uses GSM, and that can send SMS messages. And in case it wasn’t obvious, you need to be in range of the cell phone provider’s radio towers. I suspect this is what you were looking for.
  • If you are wanting to connect to a specific nearby phone, it may be simpler to use bluetooth, and not bother sending SMS messages.

the gsm is the option I would go for, I have seen a set up for the laser trip wire with only sounding an alarm and unsure what part of the code I would have to change