Pneumatic Programming

I am the programmer of the Unionville High School Robotics Team, Team 849…

My engeneering leader wants me to program the pneumatics with relays…the pneumatic will have to go up, down, and be stationary…according to my knowledge, relays can only send a ‘1’ and a ‘0’…given that the relay can only send two options and i need to to send three, I believe it is impossible to program the pneumatic…

Am I tooo dumb to find a solution to this? or is it really impossible? what should I do? should I use the speed controllers instead???


This is true, a relay can either be 1 or 0, but you have 2 directions. relayX_fwd and relayX_rev (or something like that in the default code) So, you actually have 4 states. 00,01,10,11. Assuming you are connected to a double solenoid you are going to have to wire up like is shown in section 3.2.3 of the robot manual, p11. Therefore the relay in forward
will trip one of the double solenoids and
the relay in reverse will trip the other. Alternately, you can connect the black wires from the double solenoids directly to ground on the terminal block. And connect the two red wires to the spike directly, one to M+, the other to M-, which avoids the use of diodes. The code is the same in either case. Just don’t turn both forward and reverse on.

thx for the info