A planing boat including: a hull having a boarding area; a screw unit having a screw, and configured to be rotatable with respect to the hull so that the expulsion direction of a water current by the screw can vary by 360 degrees; and a direction change mechanism having a turning drive force source, and configured to change the expulsion direction by rotating the screw unit with respect to the hull with a drive force of the turning drive force source.

A propulsor is described in which rotation of the frustum of a right circular cylinder generates thrust. Variants of this basic geometrical shape are also described that enable multiple means for propelling fluid past the propulsor.

An apparatus for collecting floating marine debris comprises a frame, a debris collection container in communication with a rear opening of the frame, a pair of helicoidal screws mounted to the frame in a symmetrical V-arrangement that tapers inwardly from a front opening of the frame to the rear opening, and at least one prime mover rotationally coupled to the pair of helicoidal screws. The prime mover is operable to rotate the helicoidal screws in opposite directions at the same angular velocity in water to move the apparatus forward through the water, such that floating marine debris enters the apparatus through the front opening, passes through the rear opening and is collected in the debris collection container.

The present invention provides a hetero-stiffness robotic device with a central body portion having a head end and a tail end. A rigid rotatable head propeller extends from the head end while a flexible rotatable tail propeller extends from the tail end. A head motor positioned in the central body portion rotates the rigid rotatable head propeller and a tail motor positioned in the central body portion rotates the flexible rotatable tail propeller. A controller independently controls a rotational speed of the head motor and the tail motor. The head and tail propellers may have helical shapes. The hetero-stiffness propulsion gives the robotic device a high level of environmental adaptivity over a wide range of viscosities. The device demonstrates advantages in linearity, straightness, bi-directional locomotion ability, and efficiency, which provides a critical competence for moving in low Reynolds number environments.

The invention relates to a fluid pump, in particular to a liquid pump having a rotor with at last one rotor blade for conveying the fluid, the rotor being variable with respect to its diameter between a first, compressed state and a second expanded state. In order to produce a simple compressibility and expandability of the rotor of the pump, it is provided according to the invention that at least one rotor blade is deformable between a first state which it assumes in the compressed state of the rotor and a second state which it assumes in the expanded state of the rotor by means of a fluid counterpressure during a rotation of the rotor during pump operation.

A hull is for a vessel and includes an elongated body rotatably connected to the vessel and a first end portion and a second end portion. The longitudinal axis of the elongated body substantially coincides with the longitudinal axis of the vessel and the elongated body is formed with a helical shape at least in a portion. The helical portion of the elongated body is provided with a star-shaped cross section.

An apparatus for collecting floating marine debris comprises a frame, a debris collection container in communication with a rear opening of the frame, a pair of helicoidal screws mounted to the frame in a symmetrical V-arrangement that tapers inwardly from a front opening of the frame to the rear opening, and at least one prime mover rotationally coupled to the pair of helicoidal screws. The prime mover is operable to rotate the helicoidal screws in opposite directions at the same angular velocity in water to move the apparatus forward through the water, such that floating marine debris enters the apparatus through the front opening, passes through the rear opening and is collected in the debris collection container.

The present invention provides a hetero-stiffness robotic device with a central body portion having a head end and a tail end. A rigid rotatable head propeller extends from the head end while a flexible rotatable tail propeller extends from the tail end. A head motor positioned in the central body portion rotates the rigid rotatable head propeller and a tail motor positioned in the central body portion rotates the flexible rotatable tail propeller. A controller independently controls a rotational speed of the head motor and the tail motor. The head and tail propellers may have helical shapes. The hetero-stiffness propulsion gives the robotic device a high level of environmental adaptivity over a wide range of viscosities. The device demonstrates advantages in linearity, straightness, bi-directional locomotion ability, and efficiency, which provides a critical competence for moving in low Reynolds number environments.

The invention relates to a fluid pump, in particular to a liquid pump having a rotor with at last one rotor blade for conveying the fluid, the rotor being variable with respect to its diameter between a first, compressed state and a second expanded state. In order to produce a simple compressibility and expandability of the rotor of the pump, it is provided according to the invention that at least one rotor blade is deformable between a first state which it assumes in the compressed state of the rotor and a second state which it assumes in the expanded state of the rotor by means of a fluid counterpressure during a rotation of the rotor during pump operation.

A planing boat including: a hull having a boarding area; a screw unit having a screw, and configured to be rotatable with respect to the hull so that the expulsion direction of a water current by the screw can vary by 360 degrees; and a direction change mechanism having a turning drive force source, and configured to change the expulsion direction by rotating the screw unit with respect to the hull with a drive force of the turning drive force source.