Over the weekend as a small project I built myself a tweeting motion detector. If someone moves inside the house an Arduino UNO is triggered to send an alarm message to my @mrgarduino twitter account. What would be even better would be to get a Raspberry Pi to send a photo as well from a webcam- will try to do this in the future. To make this project you need an Arduino, Ethernet shield and a motion sensor connected to PIN 4 of the Arduino. I also used an LED (set on PIN 6) to check when the motion sensor was triggered – it flashes every two seconds for 200ms but when an event triggers the sensor it stays on longer.You will also need the PString Library (Google is your friend) and check the network settings.
I run an extra-mural electronics club and we were lucky enough to get hold of some Arduinos – credit card sized computers that can be programmed from a PC and used in just about any project you can think of. The Students and myself basically get to tinker away with electronics which is awesome – watch this space for project updates. I also work with Sumbandila, a non-profit organisation in the field of secondary education which provides an educational outreach programme to impoverished rural children in Limpopo. Sumbandila ran a holiday school a few weeks ago and we got the students programing the Arduinos too! It was fantastic. We built a little traffic light LED shield (a circuit that mounts on top of the Arduino) and the students could program it themselves. It was very impressive to see these kids going from having a very limited knowledge of programming to getting all the LED traffic lights flashing in order – with minimal input from myself. Arduino is an open source system I would recommend to any ICT or Science department. Give it a go!
I’ve been running an electronics club as an extra mural activity for students at my school for several years now. We started off building simple kits such as Velleman, Kemo and RSE who are based in JHB (rse.apexmedia.co.za) but we have now started to branch out and build our own circuits. Students have built LED signs, radios and recently started to use Arduinos (www.robotics.org.za) to build more complex projects such as a tweeting weather station (www.twitter.com/ridgewayweather). One circuit I really want to get the new students to build is the joule thief. I’d never heard of it before I came across it on hackaday.com. The joule thief works in a very simple way. Basically take a used battery and the joule thief will build up a store of electrical energy in its toroid and release it as a pulse at a much higher voltage than the dead battery could – perfect for lighting up LEDs. At 40,000 times a second your eye can’t see the pulses, you simply see a working LED. I built a messy working version to test it out and have ordered all the parts of ebay. Let’s see if the students can build it – watch this space…