In this project the ultrasonic sensor is used to detect the distance of an object from the point. As the object is closer to the sensor the LED brightness gets low similarly as the distance increases the LED brightness also increases.
You can check out the video of Distance measurement with arduino and ultrasonic sensor and download the same arduino program which we have used in order to measure distance in arduino.
So share your thoughts about the project or what more ideas you have in below ! :) Any suggestions are appreciated :)