Tag Archives: rgb led

RGB, RGBW, Digital RGB, Arduino, Z-Wave, XBee / ZigBee, Raspberry Pi, JeeNode…….decisions, decisions!

I dabbled with RGB LED strips three or four years ago and used some simple “warm white” ones for our kitchen under cupboard lighting (I still have a blog post planned for that!) and some “cool white” ones for my work bench in the garage (and another blog post for that!)

During those experiments I bought some JeeLabs LED Nodes and ended up buying four or five 5m rolls of RGB 5050 LED strips just to find some that were “common anode” where the LEDs are commoned together with the positive, as opposed to “common cathode” where the LEDs are commoned together with the negative.  Unfortunately at the time the cheapest RGB LED strips came via eBay but the mainly non-english speaking sellers were difficult to extract any information out of, so buying several rolls and taking a gamble was the only way forward!

A project sitting quite high on the to-do list is “stairway lighting” – I need to illuminate the stairs in some fashion at night.  Of course, we have hall lighting upstairs and downstairs, but when we go up to bed at night and turn the light off in the downstairs hall, it’s pretty dark getting up the stairs to our bedroom.  And turning the upstairs hall light on is not a wise idea with two children asleep in their rooms.  The current workaround has my Z-Wave controller, a MiCasaVerde Vera, turning on our bedroom light to around 10% when the alarm is set (via integration with our Visonic PowerMax+).  This just about casts enough light down the stairs to see by, but obviously if one of us needs to go downstairs in the night we can’t really be turning the light on in the bedroom just to light the way!

So, I’ve been giving some thought to potential solutions.  As mentioned, I already have a shed load of LED strip rolls going spare.  I have Arduinos, Raspberry Pis, JeeNodes and XBee / ZigBee boards also sat in the spares cupboard.  And I also know that Fibaro have recently released a cracking new RGBW Controller module.  What to choose!?!?

In any situation like this, I always heed my own advice and follow the 10 Home Automation Commandments, so let’s run this project through using that logic:

1) Thou shall clearly define the goal.

Pretty simple – light the stairway when it’s dark with some low level lighting that allows us to walk upstairs or downstairs in safety.  I don’t want the light on all the time though, so it needs to switch on automatically in response to somebody starting to walk up or down the stairs and then switch off again afterwards.  I want the light level to be adjustable both in intensity and in colour.  It also needs to be controllable remotely, not just a standalone solution – for example in the event of a fire or other such emergency I want to be able to light the way to the front door for us to follow.

2) Thou shall Google it, Bing it or Yahoo it.

Yup, been considering this project for nearly a year now, so plenty of research has been carried out along the way.  One of my favourite bloggers has recently completed a similar project too, so plenty of inspiration there.  Lots of notes and scraps of paper in the projects file.

3) Thou shall choose the most cost effective way to achieve the goal.

I’m off to a good start with this one, since I already have a lot of kit in the spares cupboard already.  One concern is that if I go with a mains powered solution, there’s no easy access to power on the stairs.  There’s a socket at the top, although I blanked that off a few years ago as it wasn’t used for anything.  I could re-instate it, but it would mean that a PSU or plug would be permanently on display.

There’s another socket at the bottom of the stairs, but that was blanked off a few years ago too when I discovered that the previous house owner had spurred it off the garage lighting ring.  To re-instate that would need some substantial electrical work to bring it onto a socket ring main in the house.

Fortunately the stairs run directly over the Consumer Unit, which is in a cupboard under them and there’s a radial circuit that goes from the CU through the wall to the toilet next door to supply a washing machine and then onwards to supply some outside lighting.  So I could probably whack a socket into that radial.  And I have plenty of hardware for doing that in the spares cupboard too!

 4) Thou shall choose a solution that can be retro-fitted.

Some sort of wireless control is definitely required, I’m not running Ethernet cables to the stairs, that would be overkill even for me!  Battery power would solve the power supply problem, but I don’t think batteries would last very long powering up to 5m of LED strip!  So aside from sorting out power, it should be a pretty simple retro-fit.

5) Thou shall choose a solution that will integrate with existing systems.

Should be pretty easy to ensure this.  14 years of Home Automation under my belt and I can pretty much interface anything to my HA system!  Ethernet, Wi-Fi, Bluetooth, RS232, RS485, 434MHz RF, 868MHz RF, 2.4GHz RF, no shortage of transport mediums available.  Higher level protocol wise I can do xAP, xPL, X10, HomeEasy (but why would I?), Visonic, Z-Wave, ZigBee.  Should be able to integrate easily enough BUT, my preference would probably be Z-Wave, since that’s the direction that most of my recent HA projects have been going in.

6) Thou shall use what you’ve already got.

Yep, spares cupboard full of stuff I can use as mentioned before.  Although if I were to go the Z-Wave route, I’m going to need to pick up one of the new Fibaro RGBW Controllers.  And if I go the Arduino route and want to use Wi-Fi, I’m going to need to acquire a Wi-Fi shield of some description.  Hmmm, so maybe my options are being limited somewhat already – with Christmas nearly upon us funds are pretty scarce so I really don’t want to spend too much money on this if I can help it!

7) Thou shall not attract the wrath of others.

Should be ok with this one.  Since there’s nothing workable in place currently and it’s a genuine problem that needs a resolution, anything that gets installed should receive favourable comments.  As long as I KISS and hit that 99.99% 🙂

8) Thou shall not run before you can walk.

Definitely could break this project up.  There’s several aspects here.  The first is detecting presence on the stairs – maybe I can install some PIRs, Infra-Red beam breaks or Pressure Sensitive Mats first to get the presence detection working.  I can track the success rate of that in my current HA system, assuming I use something that can integrate to it like Visonic or Z-Wave.

The second aspect is the lighting itself – a work bench mock-up of possible solutions is probably in order to aid the process.

The third aspect is the remote control side – maybe this could be an autonomous solution as the first stage, with the remote functionality added at a later stage.

9) Thou shall plan for the future.

Definitely, that’s what the remote control side is for really!  But wait, maybe that presence detection on the stairs could also be used as additional input to the alarm system?

Or, instead of just a flashing line of LEDs, maybe some “Christmas Tree” lighting pattern effects could be useful in the future?  In the event of a fire it would be great to indicate direction of egress.  So that would rule out the simple RGB LED strips and would mean using Digital RGB LED strips based on the WS2801 or WS2811 chips.  Or how about these new WS2812, an RGB LED with a WS2811 built into it!!  But going down that route would also rule out Z-Wave.

10) Thou shall not re-invent the wheel (unless you have to).

Might have to break this Commandment!  Yes, there’s thousands of pages of information on the Internet of people having carried out very similar projects.  But, unfortunately, none that appear to meet all the goals I’ve laid out above.  So it might just mean coming up with something from scratch.  Although I dare say that I’ll probably be re-using some of those ideas, hardware details and code……so maybe this Commandment will just be bent slightly and not broken after all 🙂

Plenty of food for thought then!!

And now things are beginning to progress somewhat.  I’ve dug through the spares cupboard and rescued the RGB LED strips, taken stock of what I’ve got Arduino, Pi and XBee wise and have started to make a plan.  I discovered that I had a roll of WS2801 RGB LEDs too which was a pleasant surprise! And tonight I have ordered one of the Fibaro RGBW Controller modules, so that should be here within a week or so.

So time permitting over the Christmas period, this project should finally get crossed off the to-do list 🙂

Thanks for reading,

Martyn Wendon