I am new to Arduino, and needed some help. I am using an Uno.
What I want to do is try and find out whether an object has crossed into a particular zone using ultrasonic sensors. Basically, we have a model of a car that we want to push past a model of a hospital, showing that the car is in a no-honking zone. I want to place an ultrasonic sensor in front of the hospital such that when the car crosses the sensor, the board recognises that it is in a silence zone.
How do I program the sensor to detect that the car has crossed it?