According to one or more embodiments disclosed herein is a method of transporting equipment between sea-surface and seafloor by providing a structure with a subsea equipment package mounted thereon. The structure is used for installation and recovery in a subsea environment by changing the buoyancy of the structure or ballasting the structure to effect a controlled sinking motion.

According to one or more embodiments disclosed herein is a method of transporting equipment between sea-surface and seafloor by providing a structure with a subsea equipment package mounted thereon. The structure is used for installation and recovery in a subsea environment by changing the buoyancy of the structure or ballasting the structure to effect a controlled sinking motion.

A waterborne vessel includes a hull structure, longitudinal and transverse drive tunnels, and one or more thrusters. The hull structure has a base and side walls forming a U-shaped cross-section, open forward and aft ends, and an open top. The drive tunnels extend through the base portion of the hull structure. Each thruster is located at a corresponding intersection of longitudinal and transverse drive tunnels. Each thruster drives water flow through the corresponding drive tunnels and is rotatable about a vertical axis among multiple different thruster orientations in which the thruster drives water flow in one direction or the other through the corresponding longitudinal or transverse drive tunnel. A method includes: lowering the vessel through water to a submerged target payload; maneuvering the vessel and/or payload to position the payload on the hull structure between the side walls; and raising the vessel and payload toward the water surface.

A waterborne vessel includes a hull structure, longitudinal and transverse drive tunnels, and one or more thrusters. The hull structure has a base and side walls forming a U-shaped cross-section, open forward and aft ends, and an open top. The drive tunnels extend through the base portion of the hull structure. Each thruster is located at a corresponding intersection of longitudinal and transverse drive tunnels. Each thruster drives water flow through the corresponding drive tunnels and is rotatable about a vertical axis among multiple different thruster orientations in which the thruster drives water flow in one direction or the other through the corresponding longitudinal or transverse drive tunnel. A method includes: lowering the vessel through water to a submerged target payload; maneuvering the vessel and/or payload to position the payload on the hull structure between the side walls; and raising the vessel and payload toward the water surface.

An autonomous tethered vehicle for recovering autonomous underwater vehicles (AUVs) is provided. The autonomous tethered vehicle includes an open-structure frame with vertical and horizontal frame members and a top surface attached to a top portion of the open-structure frame. The autonomous tethered vehicle further includes at least four horizontal thrusters operable to provide lateral maneuvering and at least two vertical thrusters operable to provide vertical thrust. Additionally, the autonomous tethered vehicle includes a plurality of onboard sensors operable to provide positional information of the autonomous tethered vehicle in reference to a nearby AUV, and an electronics housing unit having a control system operable to collect data from the plurality of the onboard sensors and make real-time operational decisions based on the collected data.

An autonomous tethered vehicle for recovering autonomous underwater vehicles (AUVs) is provided. The autonomous tethered vehicle includes an open-structure frame with vertical and horizontal frame members and a top surface attached to a top portion of the open-structure frame. The autonomous tethered vehicle further includes at least four horizontal thrusters operable to provide lateral maneuvering and at least two vertical thrusters operable to provide vertical thrust. Additionally, the autonomous tethered vehicle includes a plurality of onboard sensors operable to provide positional information of the autonomous tethered vehicle in reference to a nearby AUV, and an electronics housing unit having a control system operable to collect data from the plurality of the onboard sensors and make real-time operational decisions based on the collected data.