A wing, a method of controlling lift on a wing, and a system to produce lift on a wing are provided. The wing may include a fore-element, an aft-element, a pivotable linkage that operatively connects the aft-element leading edge to the fore-element trailing edge in a span-wise direction, and an actuator. The actuator may deflect the aft-element through a predetermined deflection angle about the pivotable linkage relative to the fore-element within less than or equal to two convective periods. The method may include deflecting a span-wise flap through the deflection angle in less than or equal to two convective periods to produce high lift. The system may include a sensor to detect an input and a controller to deflect the span-wise flap of the wing by the deflection angle in not more than two convective periods based on the received input signal.

A linear drive system adapted for repetitive driving using a linear motor. Linkages are used to maintain the driven portion in linear motion. A coupled dual drive system in which two driven portions are coupled such that their coupled motions travel at the same velocity in opposed directions. A linear drive system with a return spring portion which is adapted to facilitate linear direction changeover. A coupled linear drive system which may be used as a mechanical power source for drive systems used in transportation and industry.

A hydrofoil craft includes: a hull including a bottom that spreads from a bow to a stern; and a hydrofoil mechanism provided on the bow side of the hull. The hull includes an accommodating recess formed therein, the accommodating recess being recessed toward the stern side between the bow and the bottom to accommodate the hydrofoil mechanism. A retreat surface is formed between the bottom and a recess main surface facing the bow side in the accommodating recess, the retreat surface extending toward the stern side in a downward direction and being connected to the bottom.

A linear drive system adapted for repetitive driving using a linear motor. The drive system may be used to power pumping hydrofoils which drive a boat or ship. Linkages are used to maintain the driven portion in linear motion. A coupled dual drive system in which two driven portions are coupled such that their coupled motions travel at the same velocity in opposed directions. The coupled linear drive system which may be used as a mechanical power source for drive systems used in transportation and industry. A boat with dual pumping hydrofoils adapted for propel a boat using the hydrofoils for both lift and propulsion.

The present invention is directed broadly to an underwater appendage assembly (10) of a marine vessel (12). The underwater appendage assembly (10) is in the form of a rudder assembly fitted to a bow section (14) of the vessel (12). The rudder assembly comprises an appendage in the form of a rudder foil (18) connected to a flapper member (20). The flapper member (20) is arranged whereby movement and more particularly pitching, of the vessel (12) induces deflection of the flapper member (20) relative to the rudder foil (18). This deflection in the flapper member (20) provides an oscillating movement of the flapper member (20) in a flapping action which is substantially synchronised with movement of the vessel (12) upward and downward. The flapping action of the flapper member (20) is effective in promoting forward propulsion of the vessel (12).

The vessels weight is wholly or partially supported by one or more fully or partially submerged hydrofoil(s). The amount of lift provided by said hydrofoil(s) is regulated as a function of that lift itself. External variables such as trim angle and vessel velocity affect total lift, and this system compensates for those variables to provide a regulated lift without the need to directly sense any of the external variables. A typical control system comprises one or more sensory inputs, a method to translate the input into a control output, and an actuator that turns the outputs into actual movements. The only sensory input for this system is the same lifting force that is being regulated. The mechanical arrangement translates that lifting force into movements that produce negative feedback by varying the angle of attack of the hydrofoil, which in turn regulates the lift produced.

A foil board with two hydrofoils is described. A first version has a single mast supporting both a leading hydrofoil wing and a trailing stabilizer wing connected to each other with a fuselage. A second version has two masts, with a front mast supporting a stabilizer wing and a rear mast that supports a hydrofoil, or with the front mast supporting the hydrofoil and the rear mast supporting the stabilizer wing. Both versions have a removable propulsion unit, which allows the user to easily remove the propulsion unit for cleaning, maintenance, repair, or even to remove it temporarily so that the foil board can be used for non-motorized applications.

A hydrofoil for a user on a body of water includes a fuselage with a V-shaped front wing and a rear stabilizer. A mast has a lower end projecting upwardly from the fuselage and an upper end fixed with an elongated deck such that the deck is parallel to the fuselage. In use, the user is pulled forward in the body of water by either a towing device, an impeller device, wave swells, or the like, such that the front wing, through hydrofoil action, raises the deck above a surface of the water. As the deck raises higher above the water, the distal tips of the front wing surface and lose lift, stabilizing the elevation of the deck above the water.

A wing, a method of controlling lift on a wing, and a system to produce lift on a wing are provided. The wing may include a fore-element, an aft-element, a pivotable linkage that operatively connects the aft-element leading edge to the fore-element trailing edge in a span-wise direction, and an actuator. The actuator may deflect the aft-element through a predetermined deflection angle about the pivotable linkage relative to the fore-element within less than or equal to two convective periods. The method may include deflecting a span-wise flap through the deflection angle in less than or equal to two convective periods to produce high lift. The system may include a sensor to detect an input and a controller to deflect the span-wise flap of the wing by the deflection angle in not more than two convective periods based on the received input signal.

The human powered hydrofoil bicycle includes multiple subsystems integrated together including a structural frame subsystem with associated steering and tiller module, a hydrofoil subsystem to provide vehicle lift, and a powertrain subsystem. The structural frame subsystem may be fitted with buoyancy modules to provide the overall vehicle with a near neutrally buoyant character. The structural frame subsystem also supports a seat for an operator and provides structural support for the steering and tiller module for the hydrofoil subsystem and the drivetrain subsystem. The hydrofoil subsystem includes multiple hydrofoil elements at lowermost portions of the vehicle. These hydrofoil elements generally include in a preferred embodiment a larger rear foil and a smaller front foil. The powertrain subsystem generally includes pedals rotatably supported on the vehicle at a convenient location for engagement and driving by feet of an operator. Power transmission elements extend from the pedals down to a prime mover such as a propeller.