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[on:]

Hi all,

I am looking at the feasibility of a DIY home automation system using an arduino. Because I am renting the place, I want to avoid doing any wiring. Is there a way to transmit data over powerlines? I read about X10, infiniteon etc but these seem to come as preassembled devices that are not so flexible.
I'm not looking for a complete system but rather a modem to transmit the data of sensors and actuate outlets accordingly. Will I have to go wireless with a 433Mhz system and a micro controller in each of the items to be controlled?

[Reply #1 on:]

Hi,

Was it the X10 tutorial you read (http://arduino.cc/en/Tutorial/x10) ?  Regardless of what you use from your Arduino end, if you're sending data wirelessly or over the power you'll need some intelligence at the far end to determine how to react to your commands.  That could be a pre-built module or another Arduino at the receiving end.

Alternatively you could connect everything to your Arduino, and both sense and actuate directly.

Some of the wireless modules are quite intelligent and actually contain their own microcontroller, so there are a lot of options depending on how far your sensors and outlets to control are from where you're intending to put your Arduino to rule them all.

Cheers ! Geoff

[Reply #2 on:]

X10, while cheap, is notoriously unreliable. This, however, depends on your home's wiring so your mileage may vary. If you decide to go the wireless route, you can get some pretty cheap wireless modules and pair them with standalone Atmel chips. As an example, my sensors all have an ATTiny84's (programmed using an ISP programmer and the Arduino IDE) paired with RFM12B Transceivers. The result costs less than $10 per node. They all run off batteries and send out and poll for periodic data, to a standalone Arduino (328P chip) which keeps track of all the sensors' data. It's also connected over I2C to a regular Arduino with an Ethernet shield so I can communicate with the Android.

Since you're not going to deal with wiring, I would recommend some sort of remote power switches that you can hack and control with your Arduino. I haven't used any, but I think others have successfully used an Arduino in conjunction with these:

http://www.amazon.com/3-pack-Wireless-Remote-Control-Outlet/dp/B0064PKG3Q/ref=sr_1_3?ie=UTF8&qid=1338042555&sr=8-3

A good resource, if you do decide to go the wireless route is JeeLabs:

http://jeelabs.net/

His libraries for the HopeRF transceivers are very powerful and easy to use.

[Reply #3 on:]

The jeelab wireless node seems very interesting, coupled with a digital potentiometer and/or a relay. Thanks!
What is the real world range of these 433Mhz transceivers?

[Reply #4 on:]

The jeelab wireless node seems very interesting, coupled with a digital potentiometer and/or a relay. Thanks!
What is the real world range of these 433Mhz transceivers?

I'm running mine at 915 and have no issues going from the front porch to my upstairs office in the back of the house.

[Reply #5 on:]

Nice. Would you recommend them?

[Reply #6 on:]

Nice. Would you recommend them?

Yes. I haven't ran into any issues with them yet. The only complaint is that there is only 1 or 2 sources for them and the shipping is a bit pricey if you're only ordering 1 or 2.

The JeeLib library makes them very easy to program and sleep if you're trying to run off of batteries. I'd also recommend the ATTiny84s if you don't need more than 5-6 pins per node and don't need a complicated program. An example would be just a simple light/temp/humid sensor that just reads the data and sends it out through the transceiver.