Traffic Signal Controller Pulls Data Over WiFi

[Travis Brown] just published a post about the traffic light controller he built. His number one goal was to make the device wireless (except for AC power) and he achieved this by using a WiFi shield for his Arduino. But there is also a separate board that provides a way for the chip to switch the AC lights.

He works for a web hosting company, and the boss wanted a fun way to display the status of the servers among other things. He chose to use the WiServer library which controls the CoperHead WiFi Shield and gives him the ability to serve simple web pages from the Arduino. When power is applied the sketch automatically connects to the AP and starts polling the company’s API for status data. If you’re not within eyesight of the traffic lights you can log into the web server and check that way.

We think [Travis] did a great job of explaining his code, and we applaud him for making proper use of the watchdog timer (something we don’t see in very many projects). This joins the pile of traffic-light display devices we’ve seen around here. We still don’t know where people are getting their hands on the things.

7 thoughts on “Traffic Signal Controller Pulls Data Over WiFi

  1. As LED traffic signals continue their inexorable march across the country, municipalities have to do something with the “obsolete” ones. Often they’ll just give them away.

    Not very long ago, the one stop light town I live in finally said sayonara to pedestrian literacy and replaced the WALK / DON’T WALK lights with the Bladerunner ones. Y’know, the ones for illiterates with the hand and the stick figure. Fortunately they don’t speak, they’d have to say “Cross Now” in 50 languages to be politically correct.

    I happened to be driving past while the change was being made, parked and asked what they were going to do with the old ones. The guys told me I could have one and into my trunk it went.

    I hung onto it over the winter then sold it on Craigslist for $25. :)

    1. Wow, most places replaced the walk/don’t walk signs with stick figures in the ’80s! Around here they are now adding signs that explain the meaning of the stick figures! (in English only)

  2. Galane has the best way of getting one, Ahh social engineering at it’s best. But I check out the local government and state excess sales and you can find these jewels a plenty among a lot of other great stuff kinda cheap.

  3. Nice use. At our university a lot of projects have them to show the current status of their software-tests… so if someone commits faulty or uncomplete code it turns red for everyone to see.

  4. You don’t know where people are getting these? Really?? A 5 second google search yields listings on eBay as well as an outfit that’s manufacturing new signals made of plastic (light weight, no paint necessary). They even sell direct, but a red, yellow, green signal is going to run you $200. At first, I thought that was expensive but not any more. If you have to repaint an old signal, it’s going to cost both time and money in addition to what you’ve already paid.

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