Abstract: A transducer system comprising a housing, an electromechanical transducer within the housing, a wicking material adjacent to a portion of the electromechanical transducer, and a multi-phase coolant solution within the housing. The multi-phase coolant solution transitions from a first phase to a second phase in response to a temperature of the electromechanical transducer exceeding a threshold temperature. In some example cases, the multi-phase coolant solution has a boiling point of less than about 60° C., which effectively defines the threshold temperature. The multi-phase coolant solution may be chosen such that it remains a liquid during a first phase (cooling via conduction), and then evaporates during a second phase (cooling via conduction and convection) as the electromechanical transducer heats up.

Abstract: A transducer system comprising a housing, an electromechanical transducer within the housing, a wicking material adjacent to a portion of the electromechanical transducer, and a multi-phase coolant solution within the housing. The multi-phase coolant solution transitions from a first phase to a second phase in response to a temperature of the electromechanical transducer exceeding a threshold temperature. In some example cases, the multi-phase coolant solution has a boiling point of less than about 60° C., which effectively defines the threshold temperature. The multi-phase coolant solution may be chosen such that it remains a liquid during a first phase (cooling via conduction), and then evaporates during a second phase (cooling via conduction and convection) as the electromechanical transducer heats up.

Abstract: A transducer system includes a housing, an electromechanical transducer within the housing, a wicking material adjacent to a portion of the electromechanical transducer, and a coolant solution within the housing. The coolant solution transitions from a liquid phase to a gaseous phase in response to a temperature of the electromechanical transducer exceeding a threshold temperature. In some example cases, the coolant solution has a boiling point of less than about 60° C., which effectively defines the threshold temperature. The coolant solution may be chosen such that it remains a liquid during a first phase (cooling via conduction), and then evaporates during a second phase (cooling via conduction and convection) as the electromechanical transducer heats up.

Abstract: An inflatable mast couplable to an underwater vehicle includes a flexible material defining an interior volume, a head structure, and a spring coupled to at least one of the flexible material and the head structure. The flexible material is designed to be filled with air to form an inflated mast structure that extends away from the underwater vehicle. The head structure is disposed at a distal end of the inflated mast structure and in some cases has a rigid shape that forms a panel having an outer surface that is flush with an outer surface of the underwater vehicle, when the mast structure is deflated and stowed. The spring is designed to provide a tensile force on at least one of the flexible material and the head structure when the flexible material is inflated to form the mast structure. A system includes the inflatable mast and a pump.

Abstract: A rollable mast system couplable to an undersea vehicle includes a mast made of a bi-stable composite material configured to roll onto itself in a first state and to stiffen into an elongated stable shape in a second state, and a head structure coupled to a distal end of the mast. The rollable mast system further includes a spool configured to support at least a portion of the bi-stable composite material in its first state and a roller in contact with the bi-stable composite material and configured to pay out the bi-stable composite material from the spool in a direction away from a hull of the undersea vehicle. The bi-stable composite material is in the first state as it passes from the spool to the roller, and the bi-stable composite material is in the second state after it passes the roller.

Abstract: An inflatable mast couplable to an underwater vehicle includes a flexible material defining an interior volume, a head structure, and a spring coupled to at least one of the flexible material and the head structure. The flexible material is designed to be filled with air to form an inflated mast structure that extends away from the underwater vehicle. The head structure is disposed at a distal end of the inflated mast structure and in some cases has a rigid shape that forms a panel having an outer surface that is flush with an outer surface of the underwater vehicle, when the mast structure is deflated and stowed. The spring is designed to provide a tensile force on at least one of the flexible material and the head structure when the flexible material is inflated to form the mast structure. A system includes the inflatable mast and a pump.

Abstract: A transducer system includes a housing having an opening, an electromechanical transducer within the housing, and an elastomeric boot over the opening. At least a portion of the elastomeric boot includes copper-comprising particles. In some applications, the copper acts as an antifouling agent and/or enhances the thermal conductivity of the elastomeric boot.

Abstract: A transducer system includes a housing, an electromechanical transducer within the housing, a wicking material adjacent to a portion of the electromechanical transducer, and a coolant solution within the housing. The coolant solution transitions from a liquid phase to a gaseous phase in response to a temperature of the electromechanical transducer exceeding a threshold temperature. In some example cases, the coolant solution has a boiling point of less than about 60° C., which effectively defines the threshold temperature. The coolant solution may be chosen such that it remains a liquid during a first phase (cooling via conduction), and then evaporates during a second phase (cooling via conduction and convection) as the electromechanical transducer heats up.

Abstract: An acoustic projector testing system using an acoustically transparent portable vessel which encloses a test apparatus is disclosed. The vessel is connected to an adapter plate which allows the test apparatus to be submerged in water. The testing system is then submerged in shallow water. An external pump fills the vessel with water and the air inside the vessel is allowed to escape through an external, sealable vent, Once all the air is evacuated, the vent is sealed. The pressure inside the vessel can be altered by adjusting the amount of water pumped into the vessel to perform necessary testing.

Abstract: A system and method for converting pressure differentials to electricity is disclosed. Initially, a first chamber is empty and a second chamber holds compressed air/fluid. When the device is disposed in the large bodies of water, due to pressure difference inside the first chamber and the ambient pressure, water fills the first chamber. As the water passes through the first chamber, it turns the turbine or creates pressure difference in transducer to produce electricity. The device descends itself in the deeper water column due to added water in first chamber. When the device obtains equilibrium, the compressed air/fluid from second chamber is allowed to flow to the first chamber to evacuate the filled water. The evacuating water again turns the turbine or creates pressure difference in transducer to produce electricity. After evacuation of water, the device will ascend itself to a shallower depth and the process repeats.

Abstract: An acoustic projector testing system using an acoustically transparent portable vessel which encloses a test apparatus is disclosed. The vessel is connected to an adapter plate which allows the test apparatus to be submerged in water. The testing system is then submerged in shallow water. An external pump fills the vessel with water and the air inside the vessel is allowed to escape through an external, sealable vent, Once all the air is evacuated, the vent is sealed. The pressure inside the vessel can be altered by adjusting the amount of water pumped into the vessel to perform necessary testing.

Abstract: A honeycomb-like shell is provided for an acoustic projector used in sonar applications to increase the bandwidth of the projector, reduce its weight, and to provide increased power density and reduced shell costs. The shell has outer and inner layers, with the honeycomb structure therebetween. The honeycomb shells have application in slotted cylindrical projectors, flextensional projectors, inverse flex tensional projectors, and oval-shaped projectors in which the honeycomb structure replaces the solid shells, with the honeycomb providing the relatively high specific stiffness required for the acoustic properties of the projector. The honeycomb shell achieves the same bending stiffness of the solid shells with less weight through the utilization of radial stiffeners between the inner and outer layers.