Is it possible , or worth the effort to run two controller boards together with one BBB ? For the purpose of using 6 thrusters and additional lights ?
I suppose it’s possible, but if all you want is additional thrusters and lights, there are probably easier ways of accomplishing this. Here is a forum post I did a year ago after making a modified controller board for Kevin Klemens to run 6 thrusters. You could do something similar, or you could build an auxiliary board that holds extra ESCs, and run the servo commands from the main controller board to the auxiliary board. For the lights, you could make a driver board, or find something already designed at Sparkfun or Adafruit, and wire it into some of the spare controller I/O lines. The ATMega 2560 on the controller board has plenty of spare I/O.
Please keep us informed on what you’re working on- we always like hearing about new ROV designs!
This is an interesting subject and I can see pros and cons for the alternatives. We are also evaluating 6 thrusters in addition to multiple cameras. The limited power supply to the thrusters is an issue if you want to go for the bluerobotics option.
what do you mean by limited power supply?
Depending on what type of thrusters you choose. PLease check: Blue Robotics/OpenROV 2.8 Hybrid ROV
What he means is that the OROV brushless motors consume around 7 amps each maximum while a BR T100 Thruster consumes 13 amps maximum.
The OROV power system is designed to supply around 20 amps continuous and around 32 amps peak. Therefore attempting to use the OROV power system directly to power six T100s will not be possible and six OROV brushless motors will consume 10 amps more than the power system can supply.
A solution to this problem is to use the OROV power system to power three of the thrusters and draw power directly from the batteries to power the other three thrusters bypassing the OROV power system. However doing this negates the power supply safeguards built into the OROV power system.