Remember that episode of Leverage (season 5, episode 3), where Alec uses Marvin to wirelessly change all the street lights green so they can catch up to an SUV? And you scoffed and said “that’s so not real!”… well actually they got it right. A new study out of the University of Michigan (PDF warning), shows just how easy it is to make your morning commute green lights all the way.
The study points out that a large portion of traffic lights in the United States communicate with each other wirelessly over the 900Mhz and 5.8Ghz ISM band with absolutely no encryption. In order to connect to the 5.8Ghz traffic signals, you simply need the SSID (which is set to broadcast) and the proper protocol. In the study the researchers used a wireless card that is not available to the public, but they do point out that with a bit of social engineering you could probably get one. Another route is the HackRF SDR, which could be used to both sniff and transmit the required protocol. Once connected to the network you will need the default username and password, which can be found on the traffic light manufacturer’s website. To gain access to the 900Mhz networks you need all of the above and a 16-bit slave ID. This can be brute forced, and as the study shows, no ID was greater than 100. Now you have full access, not to just one traffic signal, but EVERY signal connected to the network.
Once on the network you have two options. The completely open debug port in the VxWorks OS which allows you to read-modify-write any memory register. Or by sending a(n) UDP packet where the last byte encodes the button pressed on the controller’s keypad. Using the remote keypad you can freeze the current intersection state, modify the signal timing, or change the state of any light. However the hardware Malfunction Management Unit (MMU) will still detect any illegal states (conflicting green or yellow lights), and take over with the familiar 4-way red flashing. Since a technician will have to come out and manually reset the traffic signal to recover from an illegal state, you could turn every intersection on the network into a 4-way stop.
So the next time you stop at a red light, and it seems to take forever to change, keep an eye out for the hacker who just green lit their commute.
Thanks for the tip [Matt]
Free-formed VFD clock
[James] doesn’t need a circuit board or even some protoboard to get the job done. He free-formed all the circuits for his VFD clock. Right now this is the only project hosted on his blog so click around to see how he got to this point.
DIY LED traffic light
Here’s a scratch-build traffic light which [Jarle] uses to display information about his server. If you’re unable to find your own storm damaged original this is a pretty easy way to build one.
FPGA space attack game
This game is running on an FPGA, but it’s not written in HDL. Instead, [Johan] wrote the game in C to run on a soft processor loaded on the gate array.
This is a fascinating idea for generating random numbers. [Gijs] is shining a laser onto a light dependent transistor. The beam of the laser is broken by the falling sand of an hourglass. This technique could be use as an entropy source for random number generation.
GPS clock source for a digital timepiece
It seems like massive overkill, but you can’t beat the time accuracy of using a GPS module as a clock source. We don’t expect that [Jay] kept the clock in one piece after finishing the project. It’s just a good way to practice decoding the GPS data.
[Brendan Sleight] has been hard at work on this wearable piece of tech. He doesn’t wear much jewelry, but a wedding ring and some cufflinks are part of his look. To add some geek he designed a set of cufflinks that function like traffic lights. Since he still had some program space left he also rolled in extra features to compliment the traffic light display.
That link goes to his working prototype post, but you’ll want to look around a bit as his posts are peppered with info from every part of the development process. The coin-sized PCB hiding inside the case plays host to a red, amber, and green surface mount LED. To either side of them you’ll find an ATtiny45 and a RV-8564-C2. The latter is a surface mount RTC with integrated crystal oscillator, perfect for a project where space is very tight.
The design uses the case as a touch sensor. Every few seconds the ATtiny wakes up to see if the link is being touched. This ensures that the coin cell isn’t drained by constantly driving the LEDs. The touch-based menu system lets you run the links like a stop light, or display the time, date, or current temperature. See a quick demo clip after the break.
Continue reading “Traffic light cufflinks”
It sounds like [Andrew] is trying to build a Pavlovian response into his behavior when it comes to online gaming. He wants to make sure he doesn’t miss out when all his friends are online, so he built this traffic signal to monitor Xbox Live activity. It will illuminate the lights, and drive the meters differently based on which of his friends are currently online. When the light’s green, he drops everything a grabs a controller.
The base of the light is a black project box. Inside you’ll find the Arduino compatible chip which drives the device mounted on a piece of protoboard. A WIZnet W5100 adds network connectivity at the low price of around $25. There is one problem with the setup. The API which [Andrew] found doesn’t use any authentication. This means that he can only see the public status of his friends; anyone who has set their online status set to private will always register as ‘online’. If you know of an existing Xbox Live API that would solve this issue we’d love to hear from you in the comments.
If you’ve ever dealt with a buggy Internet connection, you know how frustrating it can be. This project takes the guesswork out of mashing F5 over and over, or simply walking over to your router and ‘turning it on and off again.’
Necessity is the mother of invention, and when the folks at the Bitlair hackerspace in Amersfoort, Netherlands got tired of opening up a terminal to see if their network connection was down at this weekend’s Haxogreen camp they did what any self-respecting hackerspace would do: make a traffic light monitor the Internet.
The traffic light is controlled by a Raspberry Pi the Bitlair folks had lying around attached to a spare traffic light they somehow obtained with a relay. Green means the Raspi can reach 22.214.171.124, red means there is no connection, and flashing lights means there is packet loss.
Not bad for a project put together in a few hours. Now if we only knew how they obtained a traffic light, ‘just lying around.’
Video after the break.
Continue reading “Checking network status with a traffic light”
[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.
Continue reading “Traffic signal controller pulls data over WiFi”
[JD] at isotope11 was looking for a way to get instant feedback whenever a developer broke a piece of software they were working on. After finding a 48 inch tall traffic light, he knew what he had to do. Now, the entire development team knows the status of their code from a traffic light hanging in the corner.
isotope11 runs a continuous integration server to do the quality assurance on their software projects. It’s a lot more flexible than the ‘compile and pray’ setup we’re used to, but then again C isn’t very well suited to test-driven development. When one of [JD]’s developers breaks a piece of code, the CI server will send a warning to an Arduino where all the electronic magic happens.
To light the traffic light, [JD] used a few relays to drive the 120 volt bulbs in the traffic light. The traffic light is very easy to read – red means something is broken, green means everything is alright, and yellow means a test suite is being run.
Check out the video of [JD]’s TDD visualization after the break.
Continue reading “Monitoring software builds with a traffic light”