Parking can be a challenge in big cities like San Francisco. Spots are scarce,regulations are confusing, and the cost is often too darn high. At the TechCrunchDisrupt hackathon recently, John Naulty reached for a Raspberry Pi to help solvesome of his parking problems.

John explained that the parking spots near his home only allow two hour parking.But he had figured out that you only get caught exceeding that if the parkingenforcement officers see your car in the same spot for more than two hours. If hecould somehow know when a meter maid’s Interceptor drives by, he would have atwo hour heads-up before he had to move his vehicle.

Here’s how the Raspberry Pi comes into play:

“I used a Raspberry Pi with the Camera Module and OpenCV as amotion detector,” Naulty explains, rattling off the long list of tech thatwent into creating Meter Maid Monitor. “The camera monitors trafficand takes photos. The pictures are uploaded to AWS, where an EC2instance running the TensorFlow supervised learning platform doesthe image recognition. I’ve trained it to recognise meter maid cars.Finally, if there’s more than a 75 percent chance of the car being ameter maid, it sends me a text message using Twilio, so I can movemy car before I get a ticket”

If this all feels a bit nefarious and subversive to you, hopefully you can at the veryleast appreciate John’s clever use of technology. Either way, if you want to see hiscode for the Raspberry Pi and for the AWS instance, head on over to his GitHubrepo for this project. If you have any other smart ideas for using Raspberry Pi tomake city parking more bearable, let’s hear ’em!