Ultrasonic sensors

Hi, How many ultrasonic sensors can I connect to Arduino Mega 2560 ? I am making an R2D2 unit and I would like to put on it all around 15 ultrasonic sensors. Do I have enough pin connection on Arduino Mega 2560 ? If not How should I wire them to Arduino Mega 2560 ? (maybe in serie) On the ultrasonic sensors description it said max 15 degree, which direction in meant (X,Y,Z)? Thanks

How many? Should be no problem with just 15. A Mega has plenty of input pins to handle just about any type of ultrasonic sensor. If you actually hit a limit you can always extend your number of input pins with something like a CD4051 multiplexer.

The 15 degree angle is the XY angle. Think of it like a cone (with a 15 degree tip) pointing at the sensor.

Thanks very clear