Arduino Burglar Alarm Sends SMS | Hacker News Reader

Arduino Burglar Alarm Sends SMS

github.com

61 pointsaimatt34 comments

This is really cool. I've actually been working on something really similar.

Early last year, we built a a breadboard with a Teensy microcontroller (instead of an Arduino) to decode signals from off-the-shelf door and window sensors. At the time, we had to reverse engineer the protocol using a oscilloscope. :) The breadboard was tethered to an Android device, which was the brain of the system (and this let us do other cool stuff, like video, networking etc).

We're much further along now (with working prototype units). If you're interesting in this kind of thing, we ARE hiring. :) (http://elarm.com)

Both an Elk M1: http://www.elkproducts.com/product-catalog/m1-gold-cross-pla... and a HAI Omni:http://www.homeauto.com/Products/HAISystems/OmniPro2/omnipro... can do this via email and can call your cell phone and speak the alarm to you and are UL listed fire/burglar system as well as fully programmable automation controllers.

They cost significantly more (about as much as a decent PC) but I would not trust my property or life to anything less honestly. My Omni has been running without reboot for years and does security/fire/hvac/irrigation/lighting/garage door control and has an iPhone app for control.

I know it's "just" an arduino talking to another PC .. but after doing some drilling, soldering, glueing, screwing and general arduino-ing myself ( http://www.youtube.com/watch?v=N9Rj-NegE6E ) well done on actually getting something designed, done and "ready". If you inspire one person to pick up an arduino then that's compliment enough !

I have been told that Burglar alarms that send SMS alerts are vulnerable to blocking devices. These are allegedly available on ebay and are already being used for this purpose.

This isn't sending SMS over the radio network, it's hitting TelAPI over (presumably) the land line. A jammer would prevent the reception of the SMS at the site, which wouldn't harm this application because the whole point is that the owner is not present and needs an alarm.

It is, however, vulnerable to the outrageous latency problems (minutes, often) the unofficial messaging gateways have. I send my wife texts to her company blackberry because it's convenient, but ultimately had to duplicate them to her gmail address to ensure that she got them fast enough.

You're right there about the jammer. But in testing, it hasn't taken more than 20 seconds so far.

This wouldn't be vulnerable to that, as the SMS is sent via a web-based API. You'd have to block the Arduino's wifi/ethernet connection.

I don't think the meth addicts burglarizing my neighborhood are that sophisticated. ;-)

I know a lot of people like the Arduino Uno but IMHO the Nano has a better layout. Bread board friendly with the same ATMega328 as the Uno.

Nice job aimatt. Good learning project.

Really cool. It reminds me of a project my brother-in-law did to receive an SMS when the Ph levels in his salt water aquarium change.

I built something similar. I used a PCEngines Alix (x86, 5w, $100ish) and the serial port on my home security system. Fun stuff!

This seems to need a computer to actually send the SMS. Would've been far more flexible to buy a cheap AT GSM modem.

This project's pretty awesome.

The cheapest way to solve the issue would be to hook it up to something like a nokia pay as you go phone over serial/bluetooth.

But a lot more expensive

Does anyone know of a cheap and simple SMS only GSM modem?

All the ones I have used were expensive industrial spec units with complex data channels.

Huawei GTM900

Has serial port which takes AT commands. Easy enough to drive it.

Costs $20 a shot.

Have you tried one of these out? Where can you buy one?

http://www.rfsolutions.co.uk/acatalog/RFS_GSM_Modules.html

I have tried out. Well documented and you can get the breakout boards for $5 but I forget precisely where. Managed to get it working in UK on O2 pay as you go. Now in junk box :(

Watch out - you need a level shifter if you're using an Arduino or something as it has 3v3 operation. I used an old(er than me) HP lab PSU and a crudely hacked up set of BC548 switches as a level shifter. You need an antenna and a sim socket (my sim was cruely soldered onto 1/0.2 solid wire and plugged into the breakout board header).

oh god, thank you so so so so much for this.

You can hack this module: http://finch.am/projects/arduinogsm/ $25

OR you can buy this arduino shield: http://www.sparkfun.com/products/9607 $100

If it doesn't have to be SMS only, there are various mass market "surf sticks" offered by providers on the cheap, marketed at laptop owners and the like. Many of them are just AT modems with serial ports tunneled through USB and then controlled by an application on the computer.

Thanks, I assumed those would need a whole series of windows drivers to initialise them. But it looks like you can just jumper straight to the RS232 interface on this chip

Anyone know a good source to get Arduino stuff (sensors, boards, etc.) in the USA?

Adafruit, Sparkfun, Pololu, Seeed Studios, Leaf Labs Also see Mouser, Digikey, Allied, et al http://leaflabs.com/distributors/ Radio Shack carries Arduino now, some do anyway. My personal favorite is Adafruit because this one time, I whined to her about her webform not accepting my name+spamtagger@emailaddress.com and she fixed it and wrote me back in like five minutes, no joke. I do not know her personally and that was the first time I had ordered anything from her.

tl;dr Limor Fried is a bad ass, buy things from her store.

You can get stuff dirt cheap straight from Hong Kong on eBay with free shipping.

I pay about half the price of what I see in most web stores.

If you are new to electronics I would suggest the arduino inventor kit. Comes with everything you need to get your feet wet.

Sparkfun.

So what's the total cost?

- What's the cheapest Arduino board that would work with this sensor? Wouldn't it be cheaper to get a Raspberry Pi?

- How much is the power supply?

- It would also be cool if there was a way to send SMS over the regular wireless, like with one of those cheap emergency cell phone plans. That would make it a really nice alarm, no need for the internet, and it can work off a PSU even if burglars shut down the power/internet.

1. You can get your hands on a Raspberry Pi?

2. Do you really want to try and optimize for cost on sub 30 dollar items in quantities of approximately 1?

3. ADH8066 GSM Modules are approximately fifty bucks. Serial port, AT commands, etc. Who knows where you can get a data carrier for reasonable cost in this country.

He shows it on a teensy, which if you're decent with a soldering iron can be done for as little as $16 + shipping. power supply is usb so no extra cost there. not sure how well talking to a phone would do directly but worth checking into.

That's right on the money, but technically I'm using a nano. Any Arduino will work though. There are knockoff Arduinos out there too, but I like to give back to the Arduino organization by buying an official board.

$16 for the whole thing? The board, the sensor, the connectors, the power supply? I don't think it's even close to that.

You can get the cheapest Arduino you can find. About $50 total probably.

I would love to see this on a Raspberry Pi, but you will likely have to do some 3v3 to 5v translation or use the upcoming Gertboard.

Are there any functional benefits to doing this with a Pi instead of an Arduino?

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