…and balls, and squares, and hearts, and stars! If you want to build your own amazing MQTT enabled duck, I spotted these LED lights in Homebase at the weekend which might be worth a try at £2.50 each:
No good if you want the full team of ducks but they look like they’d make decent ambient objects. I seem to have a collection of half finished projects already so I didn’t buy one… this time!
The hardware side of my ambient orb project is almost finished, so I’ve been making a start at the other end: getting some data to display. Top of my wish list is to display a basic weather forecast on the orbs, which looks like it could be nice and simple thanks to the very handy Weather Underground service. There’s a decent weather station nearby for current readings, and the forecast for Southampton has been pretty accurate so far, both of which are available through the Weather Underground API.
I could process the resulting XML on my home server but, having been doing some work with mashups recently, I thought I’d create a feed mashup instead. I’ve played with Yahoo Pipes in the past but this time I created a feed using Mashup Hub on Lotus Greenhouse:
So that screen shot is probably not all that helpful in understanding what’s going on; this style of graphical programming is fairly common these days but I would personally like to see more advanced ways to document and share diagrams like this. Still, this one is pretty simple, so here’s a quick overview:
Which all ends up being published as a much simpler piece of XML. I could just grab this XML directly and process it on the Arduino, or I could save some effort and convert the mashed up XML to an even simpler comma separated list using an XML to CSV converter written for the Pachube community. Well, now it would be trivial to create a Pachube feed for the weather forecast as well… so here it is…
Perhaps not the most direct route for getting a weather forecast but I think it’s a nice example of how anyone can pull together data they are interested in without any programming, or a server of their own. I’m also quite please with the results of the forecasts so far; 13 C and clear tomorrow in theory!
Well, the polar bears have begun their migration back north to the loft. It was my first experiment with an ambient device and the Christmas tree was certainly hard to ignore, especially when Jo complained the bears had gone off again! As a result, I updated the arduino sketch a bit to just briefly flash the bears off every three minutes when our energy use was high instead of turning them off completely. Still annoying apparently (kind of the point!) but the bears did manage to stay under arduino control all Christmas with only a few breaks on manual! A few observations now that the experiment is over:
It’s not quite the sort of do it yourself which B&Q is traditionally known for but ‘Lights by B&Q‘ is looking like a perfect ambient orb kit. I almost managed to resist getting one while buying paint for the bathroom, but it just looked too tempting…
Getting inside was easy, with just a few screws holding the back in place. Once in, there’s a simple string of little circuit boards glued to plastic balls. A bit of levering popped the first one off to reveal a set of three LEDs, and it looks like they’re soldered on in a common anode arrangement…
You could just ditch the RGB circuits completely and pop in a few blinkms but I’d like to reuse what’s already in B&Q’s handy kit. I think it should be possible to cut the tracks to the colour changing circuit and wire the LEDs up to an Arduino instead. The problem is that there aren’t enough PWM outputs on a single Arduino to drive three RGB orbs. Fortunately a combination of a TLC5940 LED driver chip, and the Arduino library to go with it, should solve that problem.
Here are a few other links which look like they could be useful for this little project:
If I get the simple version working, I’d eventually like to get it working wirelessly. It would be much more useful if the orbs could be plugged in anywhere in the house rather than being connected to my home server via USB the whole time.
Update: not to be outdone, it looks like Homebase have a selection of (far cheaper) ambient orb kits as well now! (23 August 2010)
I was only in B&Q to buy some paint, but spotted this on a slightly scenic route to the paint aisle…
I almost had enough will power not to buy it but it was too tempting. It’s just too perfect for some hacking; 1 arduino + 1 B&Q LED disco lamp = 3 ambient orbs I’m thinking. The back even has four screws for easy access… which I’m not going to touch until after painting the bathroom, getting married and having a honeymoon!
Notes from a small field 