Abstract: A boat gate system for controlling vessel access to a port or similar waterbody has a number of connected, floating Port Security Barrier (“PSB”) segments. A remote latching and unlatching mechanism, combined with a powered mover mounted on one or more PSB segments, permits remote unlatching of the PSB segments; moving the PSB segments to a desired location (whether rotating same about a point, or moving a longer section laterally) so as to open the PSB, then moving the PSBs back to a closed position and latching same. Both the unlatching, movement, and latching are remotely controlled. Positional indicators, for example Global Positioning Systems or similar systems, are provided to monitor and assist in controlling PSB segment movement and unlatching, and movement of the PSB segments in a desired direction to a desired location.

Abstract: A vessel barrier system to prevent vessel movement through a passageway includes a flexible vessel barrier element coupled to one or more energy dissipating units. The vessel barrier element may be a single, typically large diameter element, for example a large diameter, high strength synthetic rope, or alternatively may be a barrier net suspended on a number of floats. The vessel barrier element is coupled by a cable to the energy dissipating unit(s), which may be large weights suspended from a frame. When a vessel contacts and moves the vessel barrier element, placing it in tension, the weights are moved from a first, lower position, to a second, elevated position. The kinetic energy of the vessel is transferred to an increase in the potential energy of the weights, and the vessel is brought to a stop. The system is particularly suitable for Large Displacement Vessels or LDVs.