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.

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.

A bionic pectoral fin propelling device based on a planetary gear train, including a frame, a power source (1), a propelling part (2), left and right maneuvering parts (3), a fixed support plate (4), a movable support plate (5), a left pectoral fin (6), a right pectoral fin (7), a fish body (8), and a tail fin (9). The fixed support plate (4) and the movable support plate (5) are installed on the frame parallel to each other; the fixed support plate (4) is located in front of the movable support plate (5); and the left and right maneuvering parts (3) are located between the fixed support plate (4) and the movable support plate (5). The present invention solves the problem that the two pectoral fins are not synchronized, realizes variable speed propelling and left/right maneuvering, facilitates increasing the bearing capacity of the propelling device, and is particularly suitable in limited space applications.

A bionic pectoral fin propelling device based on a planetary gear train, including a frame, a power source (1), a propelling part (2), left and right maneuvering parts (3), a fixed support plate (4), a movable support plate (5), a left pectoral fin (6), a right pectoral fin (7), a fish body (8), and a tail fin (9). The fixed support plate (4) and the movable support plate (5) are installed on the frame parallel to each other; the fixed support plate (4) is located in front of the movable support plate (5); and the left and right maneuvering parts (3) are located between the fixed support plate (4) and the movable support plate (5). The present invention solves the problem that the two pectoral fins are not synchronized, realizes variable speed propelling and left/right maneuvering, facilitates increasing the bearing capacity of the propelling device, and is particularly suitable in limited space applications.

Disclosed is a human powered water walker having a plurality of two-position flippers for effecting propulsion and steering of the water walker when the same is is actuated by human power. Each of the flippers is beveled at its front end and has at its rear end a downwardly beveled tab. The water walker may have two interlaced boyant ski trimarans to which the flippers are connected.

Disclosed is a human powered water walker having a plurality of two-position flippers for effecting propulsion and steering of the water walker when the same is is actuated by human power. Each of the flippers is beveled at its front end and has at its rear end a downwardly beveled tab. The water walker may have two interlaced boyant ski trimarans to which the flippers are connected.

A mechanical system includes a curved beam and a motor coupled to the curved beam. The curved beam is configured to buckle at two different locations along the positive and negative portions of its load/displacement curve, corresponding to opposite and equal sense bending directions. The motor is configured to impart a flapping motion to the curved beam.

A mechanical system includes a curved beam and a motor coupled to the curved beam. The curved beam is configured to buckle at two different locations along the positive and negative portions of its load/displacement curve, corresponding to opposite and equal sense bending directions. The motor is configured to impart a flapping motion to the curved beam.

A watercraft includes a first pontoon slidably coupled to a second pontoon, at least one paddle coupled to the first pontoon, and at least one other paddle coupled to the second pontoon. A propulsion mechanism moves the paddles reciprocally when the pontoons move reciprocally relative to each other, with the paddles moving faster than the pontoons. The propulsion mechanism can include cables engaging pulleys carried by the pontoons, translating the reciprocating motion into paddle movement. The watercraft features paddle cavities on the undersides of the pontoons, housing paddle spacers and retaining rollers. A paddle retractor, such as a torsion spring, biases the paddles to retract when moving forward and deploy when moving rearward. A sliding connector with rollers ensures smooth reciprocal movement of the pontoons. Alternative propulsion mechanisms include racks and gears or belts and gears, optimizing the translation of reciprocating motion into forward thrust.

A watercraft includes a first pontoon slidably coupled to a second pontoon, at least one paddle coupled to the first pontoon, and at least one other paddle coupled to the second pontoon. A propulsion mechanism moves the paddles reciprocally when the pontoons move reciprocally relative to each other, with the paddles moving faster than the pontoons. The propulsion mechanism can include cables engaging pulleys carried by the pontoons, translating the reciprocating motion into paddle movement. The watercraft features paddle cavities on the undersides of the pontoons, housing paddle spacers and retaining rollers. A paddle retractor, such as a torsion spring, biases the paddles to retract when moving forward and deploy when moving rearward. A sliding connector with rollers ensures smooth reciprocal movement of the pontoons. Alternative propulsion mechanisms include racks and gears or belts and gears, optimizing the translation of reciprocating motion into forward thrust.