Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing comprising a disk, accelerating thrust fluid and propelling the robotic fish.

Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust. The system can be operated in reverse, to generate electric power when the system is in a flowing stream of thrust fluid.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust. The system can be operated in reverse, to generate electric power when the system is in a flowing stream of thrust fluid.

Abstract: A low profile brooder is provided, comprising a venturi, a burner base, a burner cap, and a baffle. The burner base and the burner cap reside adjacent to each other, with the burner cap disposed above the burner base and with a distribution chamber between them. A central axis is defined. A venturi resides below the burner base and is in fluid communication with the distribution chamber at the central axis. The venturi defines a fuel flow path between its upstream and downstream ends. The fuel flow path resides at least partially at one or more of an acute angle, a perpendicular angle, and an obtuse angle to the central axis. A baffle resides in the distribution chamber between the central axis and the periphery.

Abstract: A robotic eel may comprise a plurality of torque reaction engines, an inertial mass, and a fin. Each of the plurality of torque reaction engines oscillates an inertial mass about an axis, producing a torque reaction on and oscillation of an external shaft. Oscillation of the external shaft bends a beam of the robotic eel. Bending the beam of the robotic eel produces at least one of a traveling or a standing wave in the beam. The traveling wave may be communicated to a second torque reaction of the plurality of torque reaction engines and to the fin, producing thrust.

Abstract: A robotic fish comprises one or more torque reaction engines and a fin, wherein the one or more torque reaction engines cyclically oscillate and is to cause one or more waves to propagate through the fin, wherein the one or more waves accelerating thrust fluid and propel the robotic fish. The robotic fish may have a shape of a flagellum, a fish, a marine mammal, or a disc. The one or more of the one or more torque reaction engines may comprise a drive shaft or may comprise no drive shaft. When the one or more of the one or more torque reaction engines comprises no drive shaft, the one or more of the one or more torque reaction engines may comprise a bearing surface of a closed ball-and-socket joint.

Abstract: A low profile brooder is provided, comprising a venturi, a burner base, a burner cap, and a baffle. The burner base and the burner cap reside adjacent to each other, with the burner cap disposed above the burner base and with a distribution chamber between them. A central axis is defined. A venturi resides below the burner base and is in fluid communication with the distribution chamber at the central axis. The venturi defines a fuel flow path between its upstream and downstream ends. The fuel flow path resides at least partially at one or more of an acute angle, a perpendicular angle, and an obtuse angle to the central axis. A baffle resides in the distribution chamber between the central axis and the periphery.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust. The system can be operated in reverse, to generate electric power when the system is in a flowing stream of thrust fluid.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust.

Abstract: A low profile brooder is provided, comprising a venturi, a burner base, a burner cap, and a baffle. The burner base and the burner cap reside adjacent to each other, with the burner cap disposed above the burner base and with a distribution chamber between them. A central axis is defined. A venturi resides below the burner base and is in fluid communication with the distribution chamber at the central axis. The venturi defines a fuel flow path between its upstream and downstream ends. The fuel flow path resides at least partially at one or more of an acute angle, a perpendicular angle, and an obtuse angle to the central axis. A baffle resides in the distribution chamber between the central axis and the periphery.

Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A robotic eel may comprise a plurality of torque reaction engines, an inertial mass, and a fin. Each of the plurality of torque reaction engines oscillates an inertial mass about an axis, producing a torque reaction on and oscillation of an external shaft. Oscillation of the external shaft bends a beam of the robotic eel. Bending the beam of the robotic eel produces at least one of a traveling or a standing wave in the beam. The traveling wave may be communicated to a second torque reaction of the plurality of torque reaction engines and to the fin, producing thrust.

Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust.

Abstract: A robotic eel may comprise a plurality of torque reaction engines, an inertial mass, and a fin. Each of the plurality of torque reaction engines oscillates an inertial mass about an axis, producing a torque reaction on and oscillation of an external shaft. Oscillation of the external shaft bends a beam of the robotic eel. Bending the beam of the robotic eel produces at least one of a traveling or a standing wave in the beam. The traveling wave may be communicated to a second torque reaction of the plurality of torque reaction engines and to the fin, producing thrust.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust. A fluke, fin, or wing comprises an angle of attack mechanism, wherein the angle of attack mechanism may use power from the fluke, fin, or wing to adjust an angle of attack of the fluke, fin, or wing relative to a surrounding thrust fluid.

Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A robotic jellyfish comprises a torque reaction engine and a jellyfish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the jellyfish body, accelerating thrust fluid and propelling the robotic jellyfish.