[Klaus] wanted some sort of aid for parking his car, and after running across a $4 ultrasonic sensor, decided to build his own speaking distance sensor (.de, Google Translation). Inside [Klaus ...

Inside the light is an Arduino Nano, which reads from the ultrasonic sensor mounted underneath the enclosure and lights up the appropriate LED depending on the car’s distance.

In addition to the Arduino, you’ll need the four wheels, batteries, infrared and ultrasonic sensors, jumper wires, a DC power switch, and several motor parts.

Seeing as Arduino is good for controlling motors and sensors, Randy added a PING ultrasonic sensor to the front of the vehicle too.