When I was looking at big trawlers I did a lot of research
on the SeaKeeper Gyro. One of the interesting issues is where and how to mount it.
All the torque from resisting the roll is transferred from the gyro thu the frame member
the gyro is attached to. Even worse, the torque is a high frequency load that is constantly changing force and direction.
Several clever engineers on a couple of the trawler
and powerboat forums
calculated the loads and they were substantial. It sounded like many power boats did not have enough structure in the frame to absorb the energy from the Seakeeper.
And, no one could figure out if constant, repetitive twisting of a frame would eventually lead to stress fractures.
They are an interesting idea.