DIY Home AutomationChris Barrett

Disclaimer

• I am a hobbyist• I have no attachments to any of the companies that

I will mention other than that I have bought some of their products.

• References to the companies and their products do not constitute endorsements.

What is Home Automation?

• “home automation”

• “smart homes”

• “intelligent houses”

• Automating aspects of your home to make things more efficient and/or enjoyable.

My Introduction to HA

The Technologies in my House

• X10

• 1-wire

• Infrared

• Text to speech

• Caller ID

• Digital IO

X10

• Powerline Carrier (PLC)

• Control signals are sent over the house’s existing electrical wiring• no extra wiring is required!

• The signals are not noticed by and don’t affect the operation of non-X10 equipment.

• Developed and patented in 1978

Examples of X10 Equipment

CM12AUComputer Interface

AM12Appliance Module

LM15EB“Socket Rocket”

X10 Addressing Scheme

• Each device (eg a light) is assigned an address• made up of a House code and Unit code

• House Code – A,B,C,…,P

• Unit Code – 1,2,3,…,16

• So a light in the kitchen might be K3

• 256 (16*16) combinations• Multiple devices can have the same code but will be

controlled as one.

Examples of X10 Commands

• K3 ON• Turns the kitchen light on

• K3 OFF• Turns the light off

• K3 DIM25• Turns the light on but at 25% of it’s normal power

X10 – “Gotcha #1”

• X10 wont work with devices that need a human to press a button for it to do something.

• The device needs to be capable of doing its job as soon as it gets power.

• For example, X10• Wont work with a VCR, but• Will generally work with a kettle or a pedestal fan.

X10 - “Gotcha #2”

• X10 signals can occasionally get lost or corrupted.

• Most X10 modules are not bi-directional.• No feedback to confirm if the command was

received.

1-wire

• Firstly, it actually uses two wires …• 1 wire for ground• 1 wire for power and data

• this is where the name comes from

• The 1-wire devices in my house use the existing Cat-5E cabling.

• Each device has a unique ID (like a MAC address)

iButton

• One physical implementation of 1-wire devices.

• Looks like a watch battery.

• Two main types used for HA:• Thermostat• Serial number

• Can be used to identify regular occupants

Infrared

• IR transceiver connected to the PC• www.usbuirt.com

• Allows the control of:• devices (eg TV, stereo, VCR) from the PC, and• the PC using a surplus IR remote.

• An IR->RF->IR repeater allows me to keep the PC and USB-UIRT in a closet.

Text To Speech

• Reads out information, reminders and warnings:• Reads out the weather forecast each morning.• Reminds me the night before and the morning of

rubbish day.• Tells me when the news is on.

Digital I/O

• Serial interface board• www.weedtech.com

• Each of the 14 lines can be configured as inputs or outputs.• Switches, LEDs, push buttons, etc

Misterhouse

• The ring master or brain of the the system.

• Open source.

• Written entirely in Perl• Multi platform – Win32, Linux, Mac, etc

• All of the automation within my house was created using Perl.

• www.misterhouse.net

Heating

• Wireless thermostat.

• PC based RF receiver (W800RF32)• www.wgldesigns.com

• The system looks at the temperature provided by the thermostat …

• Compares it to my desired temperature for the time of day …

• If necessary sends commands to an X10 controllable relay which in turn controls the ducted gas heater.

Motion Detectors

• Generally one in each room.

• In some rooms, the lights are turned on automatically if motion is detected and it’s dark.

• In all rooms, the lights are turned off if no motion is detected for a user-defined period of time.

Motion Detectors

• Can double as sensors for an security system.

• A work in progress at this stage.

Doors

• The front and back doors are fitted with devices that send a signal whenever the doors are opened or closed.

• The system advises when a door has been left open too long.

• A device has also been fitted to a closet and a light is turned when on the door is opened.• just like the fridge.

Doorbell

• Plays a WAV file when someone presses the button.

• If the front door is not opened within 45 seconds then an email is sent to me indicating that we missed a visitor.

• Future plan is to install a camera (eg web cam) to take a photo and include it in the email.

The code that manages the doorbell$Doorbell_timer = new Timer(); $Doorbell_Answer_timer = new Timer();

if (state_now $Doorbell =~ /normal/) { play(volume=>100, file=>'Trumpet1.wav'); flash $LoungeRoom_light; if (inactive $Doorbell_timer) {

set $Doorbell_Answer_timer (45); set $Doorbell_timer (120);

} } if (expired $Doorbell_Answer_timer) {

Send_Email(undef,"Doorbell"," No-one answered the door",undef); } if ((state_now $FrontDoor eq "open") && (active $Doorbell_Answer_timer)) {

unset $Doorbell_Answer_timer; print_log "Door has been answered - email will not be sent";

}

Caller ID

• Modem detects the phone ringing.

• The system:• reads the phone number from the modem,• looks up a database of phone numbers and reads

out the name if it’s known or the phone number, and• sends an IR signal to the stereo to turn down the

volume.

Weather Data

• The system downloads:• Weather conditions (current temp, wind speed, etc)

from the Bureau of Meteorology every 20 minutes.• Forecast information once an hour.

• Conditions are plotted on a number of graphs.

• Forecast is read out each morning, and when requested.

Irrigation

• Project is on hold because of the water restrictions.

• Plan is to have a system that will adjust watering parameters depending on:• the forecast for today and the next couple of days, • the current conditions, • the recent past conditions, and• any government imposed watering restrictions.

Example #1- My computer room

Each morning when I walk into the room for the first time, the system:

1. Turns on the light if it’s dark,

2. Reads out the forecast for the day,

3. Reminds me if our dog needs its monthly pills, and

4. Turns on the radio in the lounge room and sets it to Triple J.

Example #2 - Rubbish Day

• We have our rubbish collected on Thursdays.

• On Wednesdays at 18:15, 19:15 and 20:15 the system announces that “It is rubbish day tomorrow.”

• On Thursday morning the system announces at 07:15 and 07:45 that “It is rubbish day today.”

Example #3 - Front door

• Motion sensor outside near the front door detects motion and turns on:• the exterior light if it’s dark outside and• the light immediately inside the front door if it’s dark

inside the house.

Example #4 - News Time

• At 17:57 the system announces that “The news is on soon”.

• At 17:59 the system transmits IR signals to:• Turn the TV on,• Set the channel on the TransACT STB to 9, and• Set the stereo to accept the audio feed from the TV.

Demonstration

• A live demonstration of the system via the Internet.