I've always thought it would be nice to have a car with a parking sensor. I don't want to spend that kind of money until I pay off my student loans. However I do have the materials to make one myself thanks to a class I took on microcontrollers. Part of my motivation is that my car doesn't make parking particularly easy. The back end is tall and it doesn't extend out very far so I'm usually too far or too close.
This project will show you how to build your own parking obstacle sensor for your car.
This obstacle sensor shows the distance in inches, cm, or mm depending on the "units" variable you can change in the code. It also displays between 0 to 16 bars in the bottom indicating 0 to 255 inches. The sonar module can only detect between 6 and 255 inches. Any less than 6 will show as 6 and any more than 255 will display as 255.
What do you need?