Modifying and Adapting

This design is made to be hacked at and restructured to fit experimenters needs.  Kids come up with the strangest robots, so it's important the the EV3 pneumatic controller has a loose design that adapts to their needs.  The focus of the two adaption below is to address the weakness of the prototype design.

Multiple Pumps Per Motor

Attaching one pump per motor is inefficient.  Without a special multiplexer, EV3 robots are limited to 4 motor connections.  With one pump per motor, we're cutting our available motors in half to double air production speed, thereby limiting the possible functionality of the rigid side of the robot.

One possibility is to mirror the gear-pump connection from one side of the motor to the other, so that the motor has two 40 tooth gears, each with one pump attached. 

Another option is to used a piston setup with two motors to connector 4 pumps between 2 motors.  Here is a picture of the piston setup (again, no pumps because of limitations of LEGO Digital Designer).

Air Tank with Servo Control Valve

One way to get past the slow air pumping is to prepump the air into a tank and release it when the necessary pneumatic actuation is necessary.  LEGO conveniently makes an air tank for their pneumatic pieces, and Mind Sensors sells a servo control valve that works with EV3.  These two pieces could be combined to create a quick pressurizing action.

Instead of waiting till till pressure is necessary to trigger the actuators, the EV3 can fill up the air tank -- only stopping if the air tank is already at capacity.  Instead of triggering the pumps when pressure is needed, the EV3 would use the servo valve control to open the valve and quickly release air from the tank.  The pressure sensor would still be in use and could close the valve to the tank if the desired pressure is met.