A release device for releasing another device in an environment includes a housing containing a material matrix. A member is restrained by the material matrix and extends outside the housing. The matrix is a solid in conditions of the environment to hold the member stationary in opposition to predetermined force. The matrix softens at a predetermined softening temperature to permit relative movement between the member and the material matrix. A heating element is disposed to heat the material matrix to the predetermined softening temperature. A method for releasing a device includes attaching the device to a member extending out of the release device. The device remains attached against the predetermined force. The matrix is heated to the softening temperature in response to a communication to permit movement of the member to fully or partially release the device.

According to exemplary inventive practice, a deployment line connects a vessel to an anchor, and a tether connects a buoyant electronic unit to the same anchor. The buoyant electronic unit includes a syntactic foam sphere, and a computer and sensors that are housed in the sphere. The anchor and the buoyant electronic unit are discharged from the vessel and sink in the water. The deployment line mechanically detaches from the anchor when the anchor reaches bottom. The buoyant electronic unit stabilizes into an equilibrium position, tethered vertically and tautly to the anchor. Measurements pertaining to phenomena such as underwater electric potential, pressure, magnetic field, and acceleration are taken by the corresponding sensors and are processed by the computer. An electrical (e.g., acoustical) signal is transmitted to detach the tether from the anchor, whereupon the buoyant electronic unit rises to a retrievable position on the surface of the water.

According to exemplary inventive practice, a deployment line connects a vessel to an anchor, and a tether connects a buoyant electronic unit to the same anchor. The buoyant electronic unit includes a syntactic foam sphere, and a computer and sensors that are housed in the sphere. The anchor and the buoyant electronic unit are discharged from the vessel and sink in the water. The deployment line mechanically detaches from the anchor when the anchor reaches bottom. The buoyant electronic unit stabilizes into an equilibrium position, tethered vertically and tautly to the anchor. Measurements pertaining to phenomena such as underwater electric potential, pressure, magnetic field, and acceleration are taken by the corresponding sensors and are processed by the computer. An electrical (e.g., acoustical) signal is transmitted to detach the tether from the anchor, whereupon the buoyant electronic unit rises to a retrievable position on the surface of the water.

A magnetic release assembly includes a housing defining a cavity, a permanent electromagnet positioned within the cavity, and a microcontroller electronically coupled with the permanent electromagnet. The microcontroller is configured to selectively provide power to the permanent electromagnet. A timer board is in communication with the microcontroller. A power source is electronically coupled with the microcontroller, the permanent electromagnet, and the timer board. The microcontroller is configured to provide power to the permanent electromagnet in response to an alarm from the timer board.

A magnetic release assembly includes a housing defining a cavity, a permanent electromagnet positioned within the cavity, and a microcontroller electronically coupled with the permanent electromagnet. The microcontroller is configured to selectively provide power to the permanent electromagnet. A timer board is in communication with the microcontroller. A power source is electronically coupled with the microcontroller, the permanent electromagnet, and the timer board. The microcontroller is configured to provide power to the permanent electromagnet in response to an alarm from the timer board.

A system includes: an anchor placed on a sea bottom; a submersible mooring cable having a first end connected to the anchor; an intermediate buoy connected to a second end of the submersible mooring cable and floating in the sea; an intermediate mooring cable having a first end connected to the intermediate buoy; an observation buoy connected to a second end of the intermediate mooring cable, and measuring ocean data of an upper layer from a sea surface to the intermediate buoy while floating and sinking between the intermediate buoy and the sea surface; and a lower layer-observation unit placed along the submersible mooring cable, and measuring ocean data of a lower layer in a location deeper than the intermediate buoy. Ocean data of a wide area between the sea surface and the sea bottom can be acquired easily.

A magnetic release assembly includes a housing defining a cavity, a permanent electromagnet positioned within the cavity, and a microcontroller electronically coupled with the permanent electromagnet. The microcontroller is configured to selectively provide power to the permanent electromagnet. A timer board is in communication with the microcontroller. A power source is electronically coupled with the microcontroller, the permanent electromagnet, and the timer board. The microcontroller is configured to provide power to the permanent electromagnet in response to an alarm from the timer board.

A magnetic release assembly includes a housing defining a cavity, a permanent electromagnet positioned within the cavity, and a microcontroller electronically coupled with the permanent electromagnet. The microcontroller is configured to selectively provide power to the permanent electromagnet. A timer board is in communication with the microcontroller. A power source is electronically coupled with the microcontroller, the permanent electromagnet, and the timer board. The microcontroller is configured to provide power to the permanent electromagnet in response to an alarm from the timer board.

Disclosed herein are systems and methods for ropeless fishing. The ropeless fishing system includes a surface subsystem installed on a vessel and at least one submerged subsystem submerged in a body of water. The surface subsystem includes acoustic transceiver and acoustic transducer units, which are configured to generate and omnidirectionally transmit an acoustic interrogation signal into the body of water surrounding the vessel and to directionally receive acoustic reply signals. The submerged subsystems include a compressed gas source and an enclosed flotation bag in fluid communication and an underwater acoustic actuator-transponder unit configured to receive the acoustic interrogation signal transmitted by the surface subsystem and to transmit an acoustic reply signal into the body of water. In addition, the submerged subsystem is further configured to control the flow of gas between the compressed gas source and the enclosed floatation bag to facilitate recovery of the submerged subsystem.

Disclosed herein are systems and methods for ropeless fishing. The ropeless fishing system includes a surface subsystem installed on a vessel and at least one submerged subsystem submerged in a body of water. The surface subsystem includes acoustic transceiver and acoustic transducer units, which are configured to generate and omnidirectionally transmit an acoustic interrogation signal into the body of water surrounding the vessel and to directionally receive acoustic reply signals. The submerged subsystems include a compressed gas source and an enclosed flotation bag in fluid communication and an underwater acoustic actuator-transponder unit configured to receive the acoustic interrogation signal transmitted by the surface subsystem and to transmit an acoustic reply signal into the body of water. In addition, the submerged subsystem is further configured to control the flow of gas between the compressed gas source and the enclosed floatation bag to facilitate recovery of the submerged subsystem.