My family and I were going outside to shop in Costco only to be stumped by the unavailability of the parking slots. We roamed around for a half an hour before we got to park. Becuase this happened often, I was motivated to create a solution to this problem with the expertise that I had gained in the past months learning Arduino.
The solution that I developed would sense the spots that are occupied and unoccupied and upadate them on a website for users to view. I used ultrasonic distance sensors with the Arduino Mega to sense the distance between the car and the ultrasonic sensor. For the sake of the concept, I built a model car parking area with six slots. Then, with a breadboard between the car parking slots, I attached the sensors. Then, I would test if there was an object in front of the sensor, and if it was I would update in the cloud SQL database with PHP. So, in the end, the user will be able to monitor a table with values of green checks or red crosses, letting the user know if there is a car parked in that slot or not. In this way, you will know where to park without having to roam around for a really long time!