...
The testing ended during a gradual pressure increase during a dive at 70+ meters, where some
of the components lost power. Many critical components lost power, including the communication board, which instantly made it possible to get any data or control the ROV further. We instantly turned off power, to prevent as much damage as possible if there was a leak. After hoisting the ROV up to the boat again, we began troubleshooting the ROV. We could not regain
control of the ROV at this point and decided to end test 3.
Further troubleshooting took place back at the lab at NTNU. During the troubleshooting all the
components inside the enclosure were checked and none of them were broken. The problem
was traced to the external box and specifically to the 16.5V converter. But, since all the components inside were encased in epoxy it was not feasible to find and fix the exact problem, and recast the external box with epoxy. The problem seems to be with either the converter itself or
the cables going from the converter to the ROV. It seems that the pressure at the 70+ meters may
have caused this, but without digging the components out of the epoxy its hard to conclude exactly.
...