A system configured for controlling a trim position of a trimmable drive unit with respect to a marine vessel. The system includes a trim actuator coupled to the trimmable drive unit and configured to rotate the trimmable drive unit about a horizontal trim axis, at least one obstruction sensor configured to sense obstructions proximate the trimmable drive unit, and a controller operably coupled to the trim actuator and the at least one obstruction sensor. The controller is configured to operate the trim actuator to rotate the trimmable drive unit about the horizontal trim axis, receive a signal from the at least one obstruction sensor indicating an obstruction within a predetermined threshold distance of the trimmable drive unit, and perform a mitigation operation to prevent the trimmable drive unit from impacting the obstruction.

A subsea structure monitoring system can include a base device configured to be secured to a subsea structure. The subsea structure monitoring system can also include a release mechanism disposed within the base device, where the release mechanism has a default state and a released state. The subsea structure monitoring system can further include a buoy detachably coupled to the release mechanism, where the buoy includes a housing that houses a communication module and a switch. The subsea structure monitoring system can also include a trigger that is configured to convert the release mechanism from the default state to the released state. The release mechanism can be converted from the default state to the released state when the trigger exerts a minimum force on the release mechanism.

An advisory system of a vessel that monitors variables of a vessel system inclusive of systems and subsystems that are used to operate the vessel. The advisory system may use machine-learning to learn from an operator (i) whether or not two variables are related to one another, and (ii) likelihood that a variable will reach a threshold, and, optionally, time until reaching the threshold. The system may receive operator feedback (i) to indicate whether the two variables are related to one another, and (ii) whether a behavior of the variable is normal or not normal. Thereafter, if a determination that the same two variables are related to one another and behaving in a similar manner, provide notification to the operator of the behavior. In response to determining that the variable is behaving (e.g., trending) in a similar manner that is not normal, providing a notification to the operator.