There is provided a hull assembly for reducing water resistance on a ship hull and improving the maneuverability on said ship. The hull assembly is mountable on a pre-existing ship hull having a bow, and a stern. The hull assembly comprises a propeller chamber for enclosing at least one propeller positioned proximate the stern of the ship hull, and a plurality of ducts attachable to an outer surface of the ship hull. The ducts extend in a longitudinal direction from a front part of the bow to the propeller chamber. The ducts have a plurality of bow openings along the bow for the water to flow directly toward the rear part of the stern, each of the ducts comprising at least one stern opening near the propeller chamber. The propeller chamber comprises two opposed chamber sides; at least one chamber opening on each of the two opposed chamber sides; and a rear opening for each of the at least one propeller.

There is provided a hull assembly for reducing water resistance on a ship hull and improving the manoeuvrability on said ship. The hull assembly is mountable on a pre-existing ship hull having a bow, and a stern. The hull assembly comprises a propeller chamber for enclosing at least one propeller positioned proximate the stern of the ship hull, and a plurality of ducts attachable to an outer surface of the ship hull. The ducts extend in a longitudinal direction from a front part of the bow to the propeller chamber. The ducts have a plurality of bow openings along the bow for the water to flow directly toward the rear part of the stern, each of the ducts comprising at least one stern opening near the propeller chamber. The propeller chamber comprises two opposed chamber sides; at least one chamber opening on each of the two opposed chamber sides; and a rear opening for each of the at least one propeller.

Shaping a wave produced by a boat traveling through the water by redirecting water from one side of the boat to the opposite side of the boat. A water inlet port and a water intake scoop on one side of the boat, a water outlet at the center or opposite side/half of the boat, a water conduit between the inlet port and the outlet, and an actuator for selectively positioning the intake scoop in one of an active position in which the intake scoop extends beyond the sides or bottom of the hull and redirects ambient water into and through the inlet port, the water conduit and the outlet, and an inactive position in which the intake scoop does not extends beyond the sides or bottom of the hull and does not redirect ambient water moving past the boat into inlet port.

A rechargeable robotic pool cleaning apparatus having a first water pump for providing a downward thrust force, a second water pump for providing at least a rearward thrust component, and a third water pump for providing at least a forward thrust component, the apparatus being buoyant when the pumps are not activated and including adjustable flap valves, baffles and nozzles to alter the outflow direction of at least some of the jet streams of water produced by the pumps so as to produce any one or more of a vertical, forward, rearward, and sideward thrust component depending upon the positioning of the baffles and/or nozzle members. At least one main controller is electronically coupled to a rechargeable power source for controlling the operation of the pumps in various combinations for moving the apparatus both vertically and horizontally in the body of water.

Shaping a wave produced by a boat traveling through the water by redirecting water from one side of the boat to the opposite side of the boat. A water inlet port and a water intake scoop on one side of the boat, a water outlet at the center or opposite side/half of the boat, a water conduit between the inlet port and the outlet, and an actuator for selectively positioning the intake scoop in one of an active position in which the intake scoop extends beyond the sides or bottom of the hull and redirects ambient water into and through the inlet port, the water conduit and the outlet, and an inactive position in which the intake scoop does not extends beyond the sides or bottom of the hull and does not redirect ambient water moving past the boat into inlet port.

A personal watercraft includes a rider operation member operated by a rider to be movable to an acceleration position for providing a forward movement command, a deceleration position for providing a rearward movement command, and a neutral position for providing an idling command, the neutral position being set to a position between the acceleration position and the deceleration position. The first operation section protrudes forward of an axis of the grip and the second operation section protrudes rearward of the axis of the grip. The first operation section and the second operation section are provided on an inner side of the grip, and the tip end of the second operation section is located inward of the tip end of the first operation section in a rightward and leftward direction. The upper end of an operation surface of the second operation section is located below the grip.

A personal watercraft includes a rider operation member operated by a rider to be movable to an acceleration position for providing a forward movement command, a deceleration position for providing a rearward movement command, and a neutral position for providing an idling command, the neutral position being set to a position between the acceleration position and the deceleration position. The first operation section protrudes forward of an axis of the grip and the second operation section protrudes rearward of the axis of the grip. The first operation section and the second operation section are provided on an inner side of the grip, and the tip end of the second operation section is located inward of the tip end of the first operation section in a rightward and leftward direction. The upper end of an operation surface of the second operation section is located below the grip.

A personal watercraft comprises a body; a driving power source mounted in the body; a water jet pump driven by the driving power source to eject a water jet in a rearward direction; a handle bar gripped by a rider; a rider operation member provided on the handle bar, the rider operation member being operated by the rider to be movable to an acceleration position for providing a forward movement command, a deceleration position for providing a rearward movement command, and a neutral position for providing an idling command, the neutral position being set to a position between the acceleration position and the deceleration position in a movement path of the rider operation member; and a control unit which controls the driving power source in response to the rider's operation for moving the rider operation member.