Brads Blog
I thought it was time for me to document some of my current projects, which I like to work on when I have some free time. Currently I'm working my own Home Automation System, and computer controlled music syncronised Christmas Lights.Computer Controlled Christmas 2009
Well it’s that time again already, Christmas is on our doorstep. During the month of November we begin putting up all our lights as it is no small task. Unpacking lights from last year can sometimes be a tangled mess, once that’s sorted all lights move onto the testing stage. Last few years I have been using mostly incandescent globes, and a few LED strings. Only problem with globes is their tendency to stop working, and are easily broken. Its a tedious task at best trying to find a bad bulb in a section, to add to that try being in the roof at dusk. Time to wheel in the wheelie-bin! In go all the incandescent light strings, it's time to upgrade to LED. I had been holding off switching to LED's as in past years they had been quite expensive, this year they were much more affordable, every dollar saved matters when you're buying 20+ sets of strings :P
LED's can be controlled by using my 240AC switching logic, but that means lots of unnecessary transformers. So this year I’m using a lower voltage switching board, which can operate up to 60VDC. The board has 16 outputs and is powered by a 350w 36vDC power supply, this supply powers ALL the LED's. Downside to this is some LED strings come with a multi function controller that take 240VAC input and provide a crude ~24VDC output. As I’m using a DC power supply I have to remove this controller and feed the DC directly into the light strings. Problem two is that depending on the combination of colours of the LED's, the requited power could be anywhere between 24v ~ 30v, hence the reason I’m using a 36v power supply.
While the LED's will operate on a full 36v, they will quickly die. So the solution is to add a resistor/s into the string to limit the voltage to the required amount. The current through each LED is circa 10mA, some colours can require up to 15mA, I've checked all my strings and Im quite happy with the brightness at 10mA. So once I've calculated the resistor size its time to solider and heat shrink it onto the string.
All ready to go! I've completed modifying all my strings and have hooked them up to the controller. I'll be putting the controller in a better enclosure next year, it will do for now :)
I've only got a few more things left to do before the Dec 1st switch on date, ill do my best to post a video up shortly.
Wishing everyone a very happy and safe Christmas!
Update: 17th Jan 2010
Christmas is well and truly over for yet another year, for some strange reason I decided it was a good idea to take down and pack up all the lights on a 35 degree day, ahhh... note to self, *bad idea!* Anyhow here are a few pics of the display and a bunch of new lights for next years display, it's always important to plan ahead :P
Home Automation Project - Update
Its an onjoing project, will it end? Probably not :P Anyhow I thought it was time for an update. The current version has been re-written in VB .Net. New features include triggering events at sunrise/sunset, current weather reports, Text to Speech and Intelligent Speech Recognition so people can interact with the system using only voice commands.
The Client application is still in its early stages, there are various parts of the interface including Irrigation, Weather Reports, CCTV, Lighting control, Audio Control & Security. They are pretty self explanatory about what each part will do so I won't go into detail.
Still on the To-Do list are building a 15" touch screen into a wooden frame which will be mounted on he wall and having the application show the front door CCTV feed when a motion sensor is triggered, or door bell pressed.
Home Automation Project
I've always been fascinated with using the computer to control real world devices. So I embarked upon this little project to teach myself more about this topic. I started out some time ago and wrote a application in VB6 to automate my irrigation system. Simple enough task, I went and purchased some inline solenoids to add to my existing irrigation system. These will open, letting the water flow through when 24v is applied. Here are a few pics of the application and the irrigation system.
I wanted to be able to control the system remotely so I developed a web interface, Its written in PHP and utilises AJAX to keep the dynamic content up to date, without having to force full page to refresh.
The original version was written in VB6, which is now quite dated. So I've moved to developing my next version in .Net. At the moment I've duplicated the exiting functionality of the old version and working on adding more features. Some of which include a standalone client which can run on another pc/pda and communicate with the server via TCP/IP. The client will be a very simple interface showing the current status of the system, and allow things to be turned on or off. I've also added options for events to trigger on sunrise/sunset and optional offset, eg sunset + 2 hrs. I also plan to incorporate my CCTV images into the application so they can be viewed by the client application, as well as any TV in the house.
Computer Controlled Christmas 2007/2008
Who doesn't love Christmas? I know my family does and we especially enjoy driving around looking at all the houses and their light displays. I grew up helping dad put up his display each year, it was the best in the street. When I moved into my own place we had a little rivalry each year about who's display was best. He'd sneakily drive past at night and see where I was at, if he thought I had a slight edge, he'd be off to bunnings the next day to purchase another 10 boxes of lights. I let him win that year, as I had big plans for the following year. Game OVER! It's time to computerise my display!
Around July 2007 I started planning my display for December. I bought quite a few new sets of lights, I'm trying to switch them all over to LED's, but they are more expensive so it will be a gradual upgrade. I've had to modify almost every set of lights I have, the reason for this is most light strings come with multifunction controllers that fade/shimmer/twinkle etc... I need to disable this functionality as the computer will be controlling this. Its time consuming work, carefully opening up each controller, soldering, testing, then resealing it.
I also had to extend the tail lead on every set of lights, as each set has to be plugged into its own circuit back at the pc. I think I used close to 400m+ of cable to achieve this, lots of solider and heat shrink were used!
The controller boards were built and housed in their own box. Luckily bunnings has power boards on special :) Lastly they were mounted on the wall in the garage and testing began. Speakers were also placed in the garden so passers by could hear the music, next Christmas I'll be using an FM tuner so people can tune in on the show in the comfort of their own car.
Overall the whole process was great fun, and dad accepted defeat :P
We were lucky enough to be a runner up in channel 7's Christmas light competition, not bad for our first attempt! Although the real pleasure comes from watching the faces of people both young and old enjoying the show. Speaking to one lady, she brought her kids every other night to see the display.