The traditional light switch works well but it's functionality is seriously limited and with increased usage of different lamps and more lighting places in room as well as home automation it's days are numbered for anything other than the basics.
Another issue affecting the traditional lightswitch is it's connection to the mains supply and the ability of the home owner to legally work on mains equipment to be able to change the light switch, or add additional light switches for other lighing.
Typically most switches have a live and return wire, this is usable where a normal lamp is installed to get power from for more intelligent switches such as the currently available home automation light switches, but now that were all changing to low power lamps the existing range of home automation light switches will struggle to be powered and switch the load correctly, and may try to dim lamps that it shouldn't
Swap the mains switch cable for a cat5 cable and you've got a versatile switch, one that the home owner can easily swap out by unplugging the RJ45 connector and plugging it into the new switch.
The other issue with the existing light switch is that it doesn't do much. On and Off, that's it. You can get dimmers but they won't work with the new lights and if you need to control more than one light, the switches multiply and as does the wiring, making it ugly.
So here's the idea:
A light switch replacement, powered by POE over a cat 5 network cable that naturally also provides all the networking connectivity. Lights are controlled using the previous high power LED lighting project (or a version of for simple switching), or other already available home automation devices.
The light switches should be able to work standalone but also communicate with a central server for more advanced functionality (i.e. controlling lights in other rooms)
The switch has at it's centre a touch screen LCD screen. This provides one touch on/off control of the light to replicate the simplicity of the existing light switch so that my nan can still work it, but with the correct “key” combination can bring up more screens to allow for better control of lighting, or other home automation control.
Where I see this getting really interesting is in the bezel area of the switch, which is packed with LEDs and sensors.
1)2x White LED Uplights for low level ambient light
2)2x White LED downlights for floor coverage
3)2x Left White LED Lights for door lighting
4)2x Right White LED lights for door lighting
5)4x IR LEDs for remote remote control (1 left and 1 right facing and 2 forward facing)
6)1x IR Sensor
7)1x Light level sensor
8)1x Temperature and Humidity Sensor (SHT15 ($28.95!)) (Maybe HIH-4030 Humidity)
9)1x ADMP401 MEMS microphone (steaming audio...)
10)1x PIR sensor
11)1x ID-12 RFID for card swipe location/pre-defined settings
12)1x Audio output (Pizo) to beep if needed
13)1x mains Relay to hook up existing switching
More details on the bezel LED's and sensors
(1)The up lights can be set for 30seconds of light when main lighting is switched off to provide enough light to get into bed, or exit the room.
(2)Combined with the up lights these could be used when the PIR senses someone in the room so to provide lighting for them to be able to navigate safely to the light switch (although the screen brightness might be enough anyway).
(3)In the even of a power failure the side lights can be used to light up the door area (assuming that like most typical installations the switch is by the door). The up and down lighters can also be used to provide low level lighting rather than having total darkness due to the power outage.
(4)See (3)
(5)By incorporating IR LEDs the switch can signal other devices in the room through the home automation network, switching off the TV or hifi, changing channel etc.
(6)When combining an IR Sensor with the IR LEDs a remote control used in one room can be channelled into another. Want to change channel on the satellite box? Fire the controller at the light switch and let the light switch in the same room as the satellite box send the signal onward. This also provides for the ability to control the light switch functionality (on/off/dim etc) using a remote contol.
(7)A simple light level sensor, useful to monitor and used to decide if to switch on lighting, such as automatic light on PIR motion detector, or timed lighting, delay lights on until dark.
(8)By monitoring the temperature and humidity in each rooms HVAC system control can be better utilised, heating only where needed, or cooling only where needed. By recording the levels a more informed choice of heating/cooling can be implemented. Always got a cold room? Or a damp room?
(9)Not really sure if this would work, but have the ability to record audio, stream off to a PC somewhere for voice decoding and have voice control for the home automation, or just inter-room paging (I.e. broadcast “Dinners ready” from the kitchen to all the other rooms, or audio devices). All very star-trek like.
(10)Detect persons in room. Switch on LCD back light and surround LEDs. Perhaps switch on room lights automatically, or more usefully switch off room lights when no movement in the room. Also able to hook into a basic alarm system to notify owner by email/sms if persons detected, get a profile of where they entered the building, where they moved around, maybe if their still in the building.
(11) Easy personalisation of settings by swiping a pre-set RFID card or token in front of the switch. Maybe the light switches by the entrance/exit can have special functions so when I swipe I can register as leaving the house or entering, and then have it arm/disarm the bugler alarm, switch off all the house lights or switch on appropriate lights so I can see my way in. Another card to switch off all house lights, or switch on all garden lights and the pond fountain etc.
(12)If room is available in the box a mains relay could be added to providing the switching available from the original light switch, minimising the changes needed to implement the home automation.
Meridian/P or Netduino backed, due to the size it would probably require a different board to the Netduino but use the same CPU etc, or dependent on the choice of screens the Meridian/P has screen controllers so might be better. The Netduino Mini looks perfect size wise but networking is not available on that device.
Fit into standard double box, or maybe single if possible. A
PICASO-GFX2 which has audio out, lots of IO so ideal for LED drive, SD card, timers, serial ports looks like a perfect display option. Screen size: 240X320xRGB 65k. 55.1x77.0x13.8 (viewing 48.6x64.8)
By using POE networking all light switches can be powered by a central UPS on the network switch so not needing any external power, and in the even of a power failure if the room is dark the bezel LEDs can be switched on providing low level lighting (about the same as a torch) so reducing the risk of trips and falls during a power fail.