On my control side I am going to have 3 DPDT switches, a potentiometer to control speed(is there a more efficient way to do this), lcd screen, and a 12v battery which will be converted down to 5v. The rov is going to be controlled using a Raspberry Pi with a USB camera and three Blue Robotics thrusters. How can I transfer all the different inputs over a cat5 cable to the ROV? Is there anything I can do to make my setup more efficient? How/where do I put the HDMI?
How do I wire the multiple inputs of the control box down a signle cat 5 cable and then have an hdmi cable go back up?
I see that no one has replied to your question so I will give it a try. Please note that I an not a computer or electronics person so my answers could be way off. It sounds like you are trying to use a mechanical DC solution to an electronics problem. Throw switch 1 up and send +dc on wire A and -dc on wire B to run motor 1 forward then throw switch 1 down to send -dc on wire A and +dc on wire B to run motor 1 backward. This will work if you have enough wires to run 1 pair to each motor. It is a straight mechanical solution.
Where you run into problems is with the number of wires you will need and the voltage loss of resistance in the wire. What most people do is put the power supply and all the “switches” in the ROV and use a remote control. The OpenROV design uses 2 wires and a homplug adapter to “digitize” the control signals from the controller and send them down the wires to the ROV. OpenROV offers a developer kit that provides the electronics you will need to do this.