Ultrasonic Garage Parking Assistant With Arduino and an ATtiny85

Hello fellow makers, I want to share with you a simple project that I have put together. I am new to prototyping/circuits and only took two semester of Java courses, so when I went looking for simple projects to build my skills, I was disappointed at how complex some of the code I saw was. While there are many other projects out there, with almost exactly the same in functionality, they were just too complex for the simplicity of the project. I believe I have put together a version that is much simpler and one that anyone can follow. In doing so, there may be some sacrifices in robustness(delay haters) but It works great so who really cares. Let’s talk about the exact functionality. We are sensing distance all the time and have an rgb LED to indicate whether to keep coming, slow down, stop, or go back. A button is used to store the current distance as the desired parking distance. Even though the LED is super low power consumption, I am an environmentalist, so lets program in a power save mode to turn off the LED when there is no car in the garage and around 30 seconds after the car has parked in the right spot. Also, we cannot expect that the car will be parked at the exact, down to the inch, distance it was set at, so we will include a range of about 6 inches. You don’t want to end up moving back and forth a dozen times before you get in right*. This is a big improvement over ones you can buy at Home Depot that only have 1, 2, and 3 foot distance settings and only 3 indicator stages. Plus, all the big box store ones look cheap and all have this ugly two part design where the LED or sensor are on a pull string. Not what I want in a classy garage. If you then want to make it smaller, cheaper and more permanent, plus, not have to leave your Arduino in it, flash the software over to an ATtiny85-20PU. We will go over all the required steps to use the Arduino as the ISP to load the software to the ATtiny.”

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