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Intruder Alarm with Text Message Notification

Small robot that can send texts to your phone based on range sensor ping interruptions

This is very easy to do and requires no soldering or advanced skills.

Heres how it works:

Range sensor detects interruption in pings --->

Calls to Temboo via WIFI --->

Tells Twilio API to send text!

This tutorial shows you how to create an intruder alarm that sends you text message alerts when motion is detected. This may sound complicated but I am pretty confident any beginner with electronics should be able to do this just fine. The range sensor senses motion and tells your Arduino board to send the text . So you can leave the intruder detector at home, connected to your network, and still receive the SMS alerts, no matter where you are, as long as you have cell phone service.

This is a pretty quick and easy project, it takes maybe 45 minutes to complete and the parts can be had for $60-$70. The main cost is an Arduino board with WIFI capabilities, however once you have that it can be used in tons of other projects and much more fun can be had...

Parts you will NEED:

-HC-SRO4 Range sensor

-Arduino Yun board or Leonardo with a WIFI shield

-4 jumper wires

-A mini breadboard (if you want)

-A 9V battery

-A 9V battery box with barrel plug and on/off switch

Links to parts and code can be found here:

Graphical instructions can be found here: 

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Your list of parts says you need an Arduino Yun or Leonardo with wifi shield.  I went to the Temboo site and it talks about all you need is the newest Arduino IDE to install


It states, "We'll show you how to get your Arduino to send SMS with Twilio" which seems to me to indicate that it will work with a regular Arduino.  Or am I misreading the documentation?

This seems pretty straightforward and might be fun to play with...



 7Turn on IoT Mode and make sure that you've added details about the shield that your Arduino board is using to connect to the internet.

So you need to be able to have your Arduino access the internet in order to communicate with Temboo and Twilio. So, an Arduino Uno will work but you still need a wifi shield or module to get it online. This link should help you get an Uno working with a WIFI shield. There are just a few extra steps. 


Scroll down to the part where it talks about what board you can use with the shield. 

Thanks for the links and the information. 

I have some ESP8266s that I bought which can be used to access the internet through a wifi network.  I am playing with them for another project, but will have to give this a try with that once I figure out the other issue.  I have seen these chips for $3 although I bought mine from Adafruit.com with a voltage regulator, diodes so you don't fry it etc for $10 versus $30 or so for the shield.  If I get this working on an Arduino Uno I will be sure to put together a how to on that. 

Thanks for publishing the how to here and on instructables.com.



I would be super interested to hear if you can get this to work with the ESP8266. Keep me posted. I found out today that I need to get some of those. 

They are amazing little devices and can be used as a controller if you want to since they have built in I/O.  I recommend the Adafruit version with the diodes, the power supply, breakout board etc. since it makes it easy to work with.  It comes with a Lua interpreter and a bunch of goodies.

Both adafruit and sparkfun have some great tutorials that are worth looking at to help you along with the setup.





How do I power these things without being bound by a USB cord? From what I understand they take 3.3v how could I do that with a rechargeable LIPO or something becuase most of them are 3.7V so i guess I use a voltage regulator? 

Good One ,,Congrats