Abstract: A pedal assembly and steering assembly are disclosed for converting an inflatable, drop stitch paddle watercraft into a pedal watercraft. The pedal assembly includes a mounting plate and mounting bracket for supporting a geared drive shaft in an opening extending through the floor of the watercraft. The steering assembly includes a rudder connected to a tiller through push pull cables.

Abstract: A biomimetic robotic manta ray includes a head cabin, a central cabin, a pair of pectoral fins and a caudal fin cabin. The pectoral fin includes a crank-rocker mechanism and a bevel gear mechanism. The biomimetic robotic manta ray achieves undulatory propulsion through a coordinated periodic motion of the crank-rocker mechanism. A complex closed motion trail of the tail end of the pectoral fin of the manta ray is traced through the coordination of the bevel gear mechanism and the crank-rocker mechanism. The biomimetic robotic manta ray achieves a combined motion of two vertical undulations superimposed on the pectoral fin of a natural manta ray. The motion trail, which has an important effect on the efficient motion of the manta ray, of the tail end of the pectoral fin is approximately simulated.

Abstract: The invention involves a paddleboard kit for converting any water sports board such as a surfboard into a paddleboard. An oar support assembly, typically secures oars with pivotal paddles to the board; facilitating rowing exercises that may be practiced while kneeling or standing. During use, the pivotable paddles pivot in such a way that the blade portion holds a steady position in relation to a shaft portion on the power stroke, whilst being free to fold in the opposite sense on the idle stroke when each stroke is executed as a substantially axial thrust of the shaft. The oar support assembly secures the pair of oars and is itself secured to the board by way of board couplers adjustably coupled to a portion of a strap that tightens to snuggly wrap around the board.

Abstract: The invention involves a paddleboard kit for converting any water sports board such as a surfboard into a paddleboard. An oar support assembly, typically secures oars with pivotal paddles to the board; facilitating rowing exercises that may be practiced while kneeling or standing. During use, the pivotable paddles pivot in such a way that the blade portion holds a steady position in relation to a shaft portion on the power stroke, whilst being free to fold in the opposite sense on the idle stroke when each stroke is executed as a substantially axial thrust of the shaft. The oar support assembly secures the pair of oars and is itself secured to the board by way of board couplers adjustably coupled to a portion of a strap that tightens to snuggly wrap around the board.

Abstract: In an oscillating fin propulsion apparatus operatively connected to a scuba diver moving on or through a body of water, a propulsive force may be produced by a pair of fins adapted to sweep back and forth in a generally transverse direction relative to the longitudinal axis of the scuba diver's body. The fins may be mounted on opposite sides of a frame detachably secured to a scuba tank. The fins may be rotatable in an oscillatory motion about respective axes coplanar to the center longitudinal axis of the frame. Drive members operable by the scuba diver may be operatively connected to the fins. The oscillating fins may provide a propulsive force to propel the scuba diver longitudinally forward during both oscillating directions of the fins as they sweep back and forth.

Abstract: A water propulsion assembly operatively connected to a watercraft moving on or through a body of water, may produce a propulsive force by sweeping fins in an oscillating motion in a generally transverse direction relative to a longitudinal axis of the watercraft. The fins may be rotatable about a first axis coplanar to the center longitudinal axis of the watercraft. Drive members rotatable about a second axis that is canted relative to the first axis may be operatively connected to the fins. The oscillatory motion of the fins may be controlled by torque applied at the canted second axis by reciprocating the drive members in a plane generally parallel to the center longitudinal axis of the watercraft. The oscillating fins may provide a propulsive force during both oscillating directions of the fins as they sweep back and forth.

Abstract: The invention involves a paddleboard kit for converting any water sports board such as a surfboard into a paddleboard. An oar support assembly, typically secures oars with pivotal paddles to the board; facilitating rowing exercises that may be practiced while kneeling or standing. During use, the pivotable paddles pivot in such a way that the blade portion holds a steady position in relation to a shaft portion on the power stroke, while being free to fold in the opposite sense on the idle stroke when each stroke is executed as a substantially axial thrust of the shaft. The oar support assembly secures the pair of oars and is itself secured to the board by way of board couplers adjustably coupled to a portion of a strap that tightens to snuggly wrap around the board.

Abstract: An apparatus for adjusting a human propelled watercraft having a pair of flexible fins extending into the water. The invention allows the user to easily adjust the propulsion device to match the user's leg length. The invention consists of a push button mechanism that converts a vertical motion into a horizontal motion allowing a locking pin to retract and the propulsion device to be adjusted. Once an adjustment position is selected, the user releases the button and a spring reverses the motion of the pin, locking the mechanism into position.

Abstract: The present invention is directed to an apparatus that allows a boat to be anchored, maneuvered, docking, and stabilized. The invention has a member that can rotate about a first axis from a stowed position to an anchored position. Or the member may be placed downwardly in the ground floor of the body of water, for maneuvering the vessel and to move the vessel in a desired direction. The hull of the vessel may have a channel for the rotation or movement of the member within the channel.

Abstract: A water propulsion apparatus operatively connected to a body moving on or through a body of water, may produce a propulsive force by sweeping fins in an oscillating motion in a generally transverse direction relative to a longitudinal axis of the body. The fins may be mounted on opposite sides of a frame and are rotatable about a first axis coplanar to the center longitudinal axis of the frame. Drive members rotatable about a second axis that is canted relative to the first axis may be operatively connected to the fins. The oscillatory motion of the fins may be controlled by torque applied at the canted second axis by reciprocating the drive members in a generally vertical plane parallel to the center longitudinal axis of the frame. The oscillating fins may provide a propulsive force during both oscillating directions of the fins as they sweep back and forth.

Abstract: A water propulsion assembly operatively connected to a watercraft moving on or through a body of water, may produce a propulsive force by sweeping fins in an oscillating motion in a generally transverse direction relative to a longitudinal axis of the watercraft. The fins may be rotatable about a first axis coplanar to the center longitudinal axis of the watercraft. Drive members rotatable about a second axis that is canted relative to the first axis may be operatively connected to the fins. The oscillatory motion of the fins may be controlled by torque applied at the canted second axis by reciprocating the drive members in a plane generally parallel to the center longitudinal axis of the watercraft. The oscillating fins may provide a propulsive force during both oscillating directions of the fins as they sweep back and forth.

Abstract: A device having a vibration based propulsion system includes at least one of an extendible and retractable diaphragm, a vibrating mechanism, and an expandable and collapsible body section for driving movement of the device. Some embodiments may also include one or more coverings configured to move to adjust the fluid resistance of the device to improve the efficiency of the device's movement. At least one processor may be connected to at least one of: a transceiver, sensors, a camera, and a drive system for controlling the operations of these mechanisms. A power source may also be attached to these elements of the device to power the device. A remote controller or other computer device may communicate with the device via the transceiver to provide input for steering the device or to receive data collected by the device.

Abstract: An anchoring system for a vessel comprising an anchoring rod, a first support member coupled to a vessel and selectively couplable to the anchoring rod, and a second support member coupled to the vessel and in a spaced relation to the first support member. The second support member retaining the anchoring rod in a slideable engagement and defining a rotation path of the anchoring rod.

Abstract: The present disclosure generally relates to the use of a self-propelled underwater vehicle for seismic data acquisition. The self-propelled underwater vehicle is adapted to gather seismic data from the seafloor and transmit such data to a control vessel. The self-propelled underwater vehicle may be redeployed to several seafloor locations during a seismic survey. Methods for real-time modeling of a target zone and redeployment of the self-propelled underwater vehicle based on the modeling are also described.

Abstract: A device for insertion in watercraft including propulsion means comprising a pair of flappers which oscillate through an arcuate path in a transverse direction with respect to the central longitudinal dimension of the watercraft. As input force is applied, the flappers twist to form an angle of attack for providing forward thrust. The means for applying propulsive force includes a pair of pedals, and further includes pedal cranks operatively associated with the propulsion means, the fore ends of the pedals being pivotally attached to a fixed point.

Abstract: A vibration-powered device adapted for flotation and propulsion on an upper surface in a liquid. The device having a body with a top side adapted to be at least partially disposed above the surface of the liquid, and a bottom side adapted to be at least partially submerged below the surface of the liquid. A vibration mechanism is disposed in the body. A propulsion fin is connected to the body. The fin includes a top side adapted to be disposed at least partially above the liquid surface, a bottom side adapted to be disposed at least partially below the surface. The vibration mechanism is adapted to oscillate the free distal end of the propulsion fin upward and downward.

Abstract: In one embodiment, a propulsion device for use in a fluid may include a crank-slider mechanism having one or more cranks, one or more connecting rods, a mast, and one or more slide structures. These structures may be arranged so that rotational motion of the shaft is translated to a combination of substantially linear motion of the mast, between an inner extent and an outer extent, and rotational motion of the mast, within an angular range between a first limit and a second limit. A flexible foil may be rigidly coupled to the mast of the crank-slider mechanism. The flexible foil may include a flexible nose portion and a flexible tail portion. The flexible tail portion may have a differing amount of flexibility than the flexible nose portion.

Abstract: A hydro-propulsion system operably coupled to a watercraft wherein the hydro-propulsion system functions to propel the watercraft. The hydro-propulsion system further includes a fluid chamber being modified-triangular in shape having walls, a bottom and a top forming an interior volume. A plurality of inlets are formed within the walls of the fluid chamber and function to allow water to flow into the interior volume thereof. An aft opening is present and is configured to allow water to flow outward from the interior volume of the fluid chamber. Disposed within the interior volume is a propulsion member that is generally rectangular in shape having a first end and a second end. The propulsion member is movably mounted within the interior volume so as to laterally oscillate proximate the second end. The hydro-propulsion system includes a leverage apparatus operably coupled to the propulsion member so as to control the movement thereof.

Abstract: The present invention is a device affording foot-powered propulsion of a watercraft by an occupant. The device consists of two levers, each with a shaft, serving as a fulcrum. When mounted on a host craft the force arms extend above the deck or floor of the vessel and each has a pedal attached to their end. The resistance arms extend beneath the hull of the craft and each has a folding paddle attached. The levers are linked so that pushing one pedal away from the operator forces the other pedal towards the operator. A back-and-forth pedaling motion moves the folding paddle blades, propelling the vessel. Direction of propulsion can be reversed by rotating the paddles 180 degrees. The invention is intended to be mounted to a watercraft, such as, a kayak that has been specifically designed for or altered to accept the device.

Abstract: Disclosed is an underwater robot based on flapping comprising: an actuator including a smart material and directional material, wherein the smart material is changed in its shape according to an external signal, and the directional material restricts a deformation in a specific direction; a body connected with the actuator; and a controller which makes the actuator perform a first stroke in a direction, and a second stroke in another direction being different from that of the first stroke; wherein the actuator performs at least one deformation of bending and twisting according to position of the smart material and directionality of the directional material, and furthermore enables to simultaneously perform the smooth bending and twisting motion with the simple structure by adjusting the position of the smart material functioning as the active component, and the directionality of the directional material functioning as the passive component.

Abstract: An internally mounted rowboat rowing fin system that includes two rotating fin assemblies mounted on the inside surface of the watercraft's opposite sidewalls. Each fin assembly includes a rotating vertical post held on the inside surface of the sidewall by a mounting tube selectively mounted or integrally formed on the sidewall. Longitudinally aligned and disposed inside each mounting tube is a hollow, elongated sleeve. Disposed inside each elongated sleeve is a rotating post that extends upward above the gunwale and into the water below the elongated sleeve. A pivoting fin arm with a flexible fin attached thereto is pivotally attached to the lower end of each rotating post. Attached to the upper end of each rotating post is a perpendicularly aligned handle bracket. A rowing handle is pivotally attached at one end to the handle hinge. During use, the two handles extend inward from the sidewall and are grasped by the rower.

Abstract: A submersible vehicle for use in water includes a vehicle body and a hybrid vehicle propulsion system to propel the vehicle body through the water. The hybrid vehicle propulsion system includes a passive thrust system and an active thrust system. The passive thrust system includes a force redirector and a buoyancy control system. The buoyancy control system is operable to selectively generate vertical thrust by varying a buoyancy of the submersible vehicle and the force redirector is configured to generate a glide thrust responsive to changes in the elevation of the submersible vehicle in the water. The active thrust system includes a thruster mechanism operable to selectively propel and/or steer the vehicle body through the water.

Abstract: A submersible apparatus (10) which can be fully submerged in a liquid medium, includes: a sealed hollow body (12) having a longitudinal main axis (A); at least one driving member (14, 36, 52) for moving the apparatus (10) horizontally and/or vertically, which can co-operate with the medium in which the apparatus (10) is submerged and which can move in relation to the hollow body (12) through an opening (22, 44, 56) provided in the wall of the body (12); and elements (18, 40, 64) for actuating the driving member (14, 36, 52), which are disposed inside the hollow body (12). The invention is characterized in that the opening (22, 44, 56) is sealed by a flexible membrane (24, 50, 58) which can deform and co-operate with the driving member (14, 36, 52) as the driving member (14, 36, 52) moves through the opening in order to move the apparatus (10).

Abstract: A human powered watercraft is disclosed. An exemplary embodiment includes a board body having a top rider surface, a bottom submerged surface, a front section half, a rear section half, a board centerline and a board plane. A leg engagement mechanism is pivotally connected to the board body positioned generally along the rear section half. The leg engagement mechanism engages a rider's legs while laying in a prone position on the top rider surface. A fin propulsion mechanism is pivotally connected to the board body positioned generally below a water line and mechanically coupled to the leg engagement mechanism. Rotating the leg engagement mechanism rotates the fin propulsion mechanism, thus creating a forward thrust.

Abstract: A vibration-powered device adapted for flotation and propulsion on an upper surface in a liquid. The device having a body with a top side adapted to be at least partially disposed above the surface of the liquid, and a bottom side adapted to be at least partially submerged below the surface of the liquid. A vibration mechanism is disposed in the body. A propulsion fin is connected to the body. The fin includes a top side adapted to be disposed at least partially above the liquid surface, a bottom side adapted to be disposed at least partially below the surface. The vibration mechanism is adapted to oscillate the free distal end of the propulsion fin upward and downward.

Abstract: A watercraft propulsion device 10 has a linkage comprising a vertical drive link (20), a support link (12), an upper control link (50) having a forwardly extended handle bar (52), and a lower propulsion link (30) having a horizontal propulsion fin (32) backwardly extended therefrom. The control and propulsion links (50, 30) are interconnected by said drive link (20), which is capable of conveying propulsive oscillatory motion to the propulsion link (30) by means of a linear power actuator (90), and by the support link (12), which is pivotally connected a transom bracket (60) about a substantially vertical axis.

Abstract: An air inflatable watercraft, having a cockpit with a bottom area forming part of the cockpit having a through opening therein adapted to receive a human operated propulsion mechanism which can be operated from the cockpit to propel the watercraft.

Abstract: Non-linear control laws are disclosed and implemented with a controller and control system for maneuvering an underwater vehicle. The control laws change the phase of one Inferior-Olive (IO) neuron with respect to another IO. One control law is global, that is, the control law works (stable and convergent) for any initial condition. The remaining three control laws are local. The control laws are obtained by applying feedback linearization, while retaining non-linear characteristics. Each control law generates a profile (time history) of the control signal to produce a desired phase difference recognizable by a controller to respond to disturbances and to maneuver an underwater vehicle.

Abstract: A watercraft having a plurality of flexible section secured to a mount, having a drive assembly, wherein the water craft can move the flexible section upwardly and downwardly to propel the watercraft through the water.

Abstract: An internally mounted rowboat rowing fin system that includes two rotating fin assemblies mounted on the inside surface of the watercraft's opposite sidewalls. Each fin assembly includes a rotating vertical post held on the inside surface of the sidewall by a mounting tube selectively mounted or integrally formed on the sidewall. Longitudinally aligned and disposed inside each mounting tube is a hollow, elongated sleeve. Disposed inside each elongated sleeve is a rotating post that extends upward above the gunwale and into the water below the elongated sleeve. A pivoting fin arm with a flexible fin attached thereto is pivotally attached to the lower end of each rotating post. Attached to the upper end of each rotating post is a perpendicularly aligned handle bracket. A rowing handle is pivotally attached at one end to the handle hinge. During use, the two handles extend inward from the sidewall and are grasped by the rower.

Abstract: A system is provided to control maneuvering flapping foils of an underwater vehicle. An oscillator generates periodic signals in which effects of external disturbances are minimized or amplified as required; the periodic signal can be either sinusoidal or can depart significantly from a sinusoid; the amplitude and frequency are varied by changing the oscillator parameters and the phase between the signals are varied by changing the parameters. The oscillator restores the parameters after a disturbance. Since the oscillator functions without external sensors, the oscillator serves as an inner-loop controller with a centralized control. An open loop control architecture for the controller, results in a motion where the vehicle maneuvers execute as force and moment commands. The non-linear, auto-catalytic oscillator can be realized using a variety of second-order differential equations.

Abstract: A propulsion apparatus is provided for propulsion in a fluid, comprising at least one propulsion fin being fixed to a fin axle, and means for driving the propulsion fin comprising a crankshaft, a pitching mechanism for rotating the propulsion fin around the axis of the fin axle, and a heave mechanism for translating the propulsion fin in a substantially transverse direction with respect to the axis of the fin axle, and where the crankshaft is driving the pitching mechanism and the heave mechanism. A simple, reliable and efficient construction is obtained by having both the heave and the pitch mechanism mounted on a single crank on the crankshaft, or to separate cranks having substantially the same radius and angular position with respect to the axis of rotation of the crankshaft.

Abstract: A jet flow propelled surfboard assembly comprises a longitudinally forwardly elongated structure including a flotation board to support a surfer and two positive displacement pumps which pistons can be manually operated in seesaw-like actions by feet of the surfer to generate jet flows to propel the surfboard assembly.

Abstract: A remote powered propulsive device having a rudder which carries a propeller or oscillating fins which are powered by pedals alone or with hydraulic assist or by an electric motor.

Abstract: A robotic architecture for capturing the autonomous performance advantages the animal models enjoy in the natural environment is disclosed. A biomimesis process is employed to allow selective utilization of basic physical components and adaptation of a common control paradigm for each of different vehicle types. The biomimetic architecture involves five functional elements: a basic biomorphic plant for capturing the biomechanical advantages of the model organism; a neural circuit-based controller consisting of a finite state machine; myomorphic actuators producing linear graded force in response to trains of current pulses for mediating movements; labeled line code output by neuromorphic sensors; and a reactive behavioral sequencer executing command sequences defined within a behavioral library.

Abstract: A human propelled watercraft having a pair of flexible fins extending into the water each adapted to oscillate through an arcurate path in a generally transverse direction with respect to the central longitudinal dimension of said watercraft. Pedals are provided for applying input force whereby as input force is applied, the flexible fins can twist to form an angle of attack for providing forward thrust with respect to the longitudinal dimension of the watercraft while moving in both directions along the arcurate path. Each of the fins preferably have a generally squared off top and an outer area of harder rubber than the inner area. Preferably, each of the fins is provided with adjustable tensioning at the trailing edge.

Abstract: A wave-powered water vehicle includes a surface float, a submerged swimmer, and a tether which connects the float and the swimmer, so that the swimmer moves up and down as a result of wave motion. The swimmer includes one or more fins which interact with the water as the swimmer moves up and down, and generate forces which propel the vehicle forward. The vehicle, which need not be manned, can carry communication and control equipment so that it can follow a course directed by signals sent to it, and so that it can record or transmit data from sensors on the vehicle.

Abstract: A watercraft having propulsion means extending below the water line comprising a pair of flexible fins each adapted to oscillate through an arcuate path in a generally transverse direction with respect to the central longitudinal dimension of said watercraft, and means operatively associated with said propulsion means for applying input force to said propulsion means whereby as input force is applied said flexible fins can twist to form an angle of attack for providing forward thrust with respect to the longitudinal dimension of the watercraft while moving in both directions along said arcuate path; the improvement wherein each of the fins preferably have a generally squared off top and an outer area of harder rubber than the inner area. Preferably, each of the fins is provided with means at the trailing edge to provide adjustable tensioning of the trailing edge, preferably by threaded means at the clew of the trailing edge.

Abstract: A motorized push pole device having a standard mounted to a raised poling platform on a boat. A housing is mounted to the standard wherein the housing is adapted to removably clamp around a push pole. A drive wheel is mounted under the housing, wherein a periphery of the drive wheel is in contact with the push pole and adapted to rotate in a first direction causing push pole to move in an extendable motion and the drive wheel adapted to rotate in an opposing second direction causing push pole to move in a retractable motion. An electrical switch is connected to a motor for controlling operation of the motor for rotating the drive wheel. The motor includes a rotating motor shaft terminating in a worm gear. The drive wheel further comprising a cog wheel for engaging the worm gear of the motor.

Abstract: An oscillating-foil type underwater propulsor with a joint provided in the invention, the propulsor including a streamline foil having a foil surface being parallel to a water surface and a span length of at least twice as long as an average chord length of the streamline foil, and a heaving mechanism undergoing heaving motion perpendicular to a propulsion direction of the propulsor and having a transmission section, wherein the transmission section is pivotally connected to the streamline foil to form a joint, the joint being provided at the middle of the span length and having a rotation center located within a circular area, which has a radius of one third of the average chord length and is centered at the point one third of the average chord length ahead of the lifting center of the streamline foil.

Abstract: Embodiments of the disclosure include a flotation device or watercraft propelled through the water using a lever powered propulsion system. The lever powered propulsion system includes human powered actuating levers operably connected to a reciprocating propulsion device. As a rider powers the levers up and down, that motion translates to the propulsion device, which cycles through a high drag propulsion phase and low drag recovery phase.

Abstract: Scuba tank compressed air can now power a dual piston compound motor driving dual water thrusters of a steady pulling underwater propulsion vehicle. Motor exhaust provides diver breathing air through a demand regulator. Motor efficiency allows continual, powerful diver thrust without curtailing normal tank dive time. Lightweight vehicle can be strapped to the scuba tank for “hands free” operation or “diver held” for driving through the water. Diver controls off/on/variable speed with a simple throttle control. Propeller or battery is not required.

Abstract: A wave-powered water vehicle includes a surface float, a submerged swimmer, and a tether which connects the float and the swimmer, so that the swimmer moves up and down as a result of wave motion. The swimmer includes one or more fins which interact with the water as the swimmer moves up and down, and generate forces which propel the vehicle forward. The vehicle, which need not be manned, can carry communication and control equipment so that it can follow a course directed by signals sent to it, and so that it can record or transmit data from sensors on the vehicle.

Abstract: Methods and apparatuses are disclosed that rotate a first member about a first point relative to a chassis, wherein the first member is rotatably coupled to a second member at a second point. A second member is counter-rotated at a ratio of the rotational speed of the first member wherein the second member is rotatably coupled to the third member at a third point. The third point is translated in response to the counter-rotating second member in oscillatory motion along a path. The third member is pivoted at a third point and fluid is moved in response to the motion of the third member. A force is applied to the chassis due to the interaction of the third member and the fluid.

Abstract: A linear actuator is provided that converts linear motion to oscillatory motion. The linear actuator includes flats, a hinge, and linear actuators. A hydrofoil is mountable on a spindle attached to the hinge. In operation, a linear push direction by the linear actuator drive causes the hydrofoil to rotate in an oscillating manner. A linear push by another linear actuator drive reverses the oscillation directions of the hydrofoil. The flats are preferably made of flexible strip metal to easily transmit motion to the spindle. The hydrofoil and spindle combine to a slot for smooth transmission of linear to oscillatory motion.

Abstract: The invention comprises a scalable, configurable “propulsor” system. A propulsor system is an assembly of individual propulsors that act in concert to form a substantially continuous control surface that undulates in a working fluid. Each propulsor is driven and configured by computer-controlled actuators so that the control surface undulates in various wave forms. Optional actuators that may refine the surface shape include an “orientation” actuator that drives rotation about the propulsor's longitudinal axis, and a “geometry” actuator that controls each propulsor's geometric configuration.

Abstract: Naval propulsion system (1), comprising a heating chamber (6), apt to be fired with refuse derived fuel, an extraction unit (3, 5) apt to extract the fuel in the form of bales housed in containers to feed it towards the heating chamber, and a unit (4) for reducing the bales to the form of fluff, positioned upstream of the heating chamber.

Abstract: A propulsion system which is designed to be used on a payload platform such as a spacecraft, satellite, aircraft or ocean vessel. To operate the system, electrical power is required. However, during operation the system does not require fuel or mass to be expelled into the environment in order to move in space. The system is designed to operate in two operational modes: in mode 1 the system incrementally moves the payload platform forward with each operational cycle. In the first mode, the system starts out with zero momentum and after moving a small distance is again left with zero momentum. In the mode 2 operation the payload platform accelerates forward a discrete increment of velocity during each operational cycle. In this second mode of operation these increments of velocity are additive.

Abstract: Devices for navigating in a fluid medium having a solid boundary include a vehicle body and a fin attached to the vehicle body. The fin is configured to oscillate relative to the body such that interaction between the fin and the fluid medium produces propulsive forces that propel the vehicle body in a desired direction in the fluid medium. The fin is also configured to rotate relative to the body along a transverse axis such that engagement between the fin and the solid boundary propels the vehicle body in a desired direction on the solid boundary.

Abstract: The invention provides a propulsion system based on “thuniform” movement of a foil member to achieve desired directional movement of a vehicle such as an unmanned submarine type of vessel. A pair of foil members are mounted to the vehicle body for reciprocating oscillating movement towards and away from each other, creating forward movement due to the compression of a fluid medium between the foil members and the expulsion of the compressed fluid rearwardly of the foil members. Each foil member is mounted to a pivot shaft for limited rotational movement with respect to the vehicle body. Damping means are connected between each pivot shaft and its associated foil member so that during operation of the propulsion system damping torque will offset hydrodynamic loads imposed on the foil members by the fluid medium. The damping means will in turn control the pitch angle of the foil members during operation, meaning that a thrust is generated for rigid foil members when moving at zero forward speed.