Building a new model rocket launch control system for the Cub Scouts. Seeking to have an RSO control opening and closing a time window where 1 - 16 Scouts can launch their own rockets semi-simultaneously.
The RSO Box's Arduino will be connected to 16 individual Continuity / Ready lights and 16 individual Launch buttons in front of those children. We countdown together....yet sometimes a Scout tries to launch early or late--to prove they have their individual control. We don't want to discourage "owning the experience," just to keep it within a known window of say 1/2 second early to 3 seconds late. So unless they press within the RSO's window, the launch commands don't get forwarded on to the Pad Boxes and ultimately to the rockets.
At the launch pads, a couple of other Arduinos each connect to eight rockets. The Pad Boxes collect the igniter wiring Continuity / Ready status read from one side of a relay. The Pad Boxes forward the Continuity / Ready status to the RSO Box. When the Pad Boxes receive individual Launch commands forwarded from the RSO Box, the Pad Box flips the relay to a high voltage side which dumps 12V 2-10A to the rocket for launch.
Now the big question: How to synchronize three Arduinos on a "longer" bus?
RSO Box <---- 15 to 35 feet ----> Pad Box #1 <---- 12 feet ----> Pad Box #2
Would prefer to keep it "built-in simple," but have seen different distance limits given for the I2C bus! What other options should I consider?
Thanks in advance.
