Buoyancy and Depth Control
The weight of the vehicle in water is offset by the air inside the hull and the float block on the top of the ROV. Ballast weights can be added or removed to achieve the desired buoyancy. Buoyancy can be affected by fresh or salt water and the buoyancy of any accessories that might be mounted on the ROV.
The depth of the Pro 4 is controlled by a vertical thruster. For the thruster to operate efficiently, the buoyancy of the ROV should be near neutral. This can be accomplished by adding or removing ballast weights that are stored in the skid pods on the bottom of the ROV. The skid pods are hinged at the rear and can be opened by unhooking the O-ring at the front. Turn the ROV over on its top to add or remove ballast. The ballast weights can be positioned within the skid pods to trim the ROV level, or pitched slightly up or down.
The procedures to adjust the buoyancy are described in the Dive Operations section of the Quick Start Instructions.