Hi David. Thanks. I will see if I can pick up some small cylinders and build a bench model to see what it takes to make it work. I would like to use this on the dive planes as well. That would probably mean using double acting cylinders. Jim K. brought this up a while back.
With reversible motors ( thrusters ) it shouldn't be a problem with dive plane angle. If the dive plane got stuck in the dive position because of seaweed or something, I can reverse the motors. In the event of a rupture or blown seal ( not likely due to the low pressure of the system ) where I lose the ability to push the dive plane, it has a fail safe so the dive plane goes to vertical. The motor mount is heavy on the back end and will also have a spring return. Once the motor/dive plane fails in vertical, a little juice to the motor, and up we go.
I don't show it on the sketch, but all the thru-hulls ( electric, hydraulic, or air ) have an isolation valve directly on the welded nipple going through the hull. In this way, I can set the dive plane angle and close the isolation valve to hold the dive plane in that position. If there's a little leakage and the dive plane starts to go back to vertical, a little stroke on the pedal will push it back down. Like I said, I'll have to build a bench system and see what valves etc. it takes to make it work.
It would be possible to set this all up on a lever where you could push it forward or back to operate the dive planes, and left or right to operate the rudders, all with just one stick. Kind of like the control stick on a helicopter or maybe closer to the wheel on an air plane.
I can still steer the sub on the surface while standing up with my head sticking out of the hatch by using the joysticks for the side thrusters which will be located in a movable control box connected via cables to the motor bus bar.. I have a sketch of that set-up that was on my frappr page a while back. It's very simple and the parts are easy to replace with off-the-shelf stuff, and inexpensive enough to carry spare parts so a dive day needn't be lost due to some small part failure.
I'll keep you guys posted on any progress I make. Frank D.