An aquatic toy that is a biomimetic fish with a watertight body portion. The body portion contains a battery electrically connected via a controller to at least one coil. The coil is positioned relative to a magnet and the coil can be caused to oscillate by virtue of a controller defined alternating current passing through the coil. The oscillation of the coil causes movement of a tail fin that is engaged to said watertight body to cause the fish to move forward through a body of water.

An aquatic toy that is a biomimetic fish with a watertight body portion. The body portion contains a battery electrically connected via a controller to at least one coil. The coil is positioned relative to a magnet and the coil can be caused to oscillate by virtue of a controller defined alternating current passing through the coil. The oscillation of the coil causes movement of a tail fin that is engaged to said watertight body to cause the fish to move forward through a body of water.

A mutually opposite generally horizontal gravity-driven flow water toy including at least first and second water inlets, at least first and second generally vertical water conduits coupled to respective ones of the at least first and second water inlets for directing a gravity flow of water therethrough from the respective ones of the first and second water inlets, at least first and second generally horizontal water conduits coupled to respective ones of the at least first and second generally vertical water conduits for directing a gravity flow of water therethrough from the respective ones of the first and second water inlets and via respective ones of the at least first and second generally vertical water conduits, the at least first and second generally horizontal water conduits being arranged such that the gravity flow of water therethrough is in generally opposite directions.

A mutually opposite generally horizontal gravity-driven flow water toy including at least first and second water inlets, at least first and second generally vertical water conduits coupled to respective ones of the at least first and second water inlets for directing a gravity flow of water therethrough from the respective ones of the first and second water inlets, at least first and second generally horizontal water conduits coupled to respective ones of the at least first and second generally vertical water conduits for directing a gravity flow of water therethrough from the respective ones of the first and second water inlets and via respective ones of the at least first and second generally vertical water conduits, the at least first and second generally horizontal water conduits being arranged such that the gravity flow of water therethrough is in generally opposite directions.

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.

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.

An underwater robotic device includes a housing unit, a control unit and a propelling unit. The housing unit includes a base seat and an upper cover in liquid-tight engagement with the base seat. The control unit is disposed within the housing unit and includes a circuit module and a center-of-gravity transferring module which is electronically connected with the circuit module. The center-of-gravity transferring module has a movable weight member and a transfer driving mechanism which drives movement of the weight member so as to vary a position of a center of gravity of the underwater robotic device and to control downward and upward moving directions of the underwater robotic device in the water. The propelling unit is connected with the housing unit and is electronically connected with the control unit to produce a propelling force to move the underwater robotic device forward in the water.

An underwater robotic device includes a housing unit, a control unit and a propelling unit. The housing unit includes a base seat and an upper cover in liquid-tight engagement with the base seat. The control unit is disposed within the housing unit and includes a circuit module and a center-of-gravity transferring module which is electronically connected with the circuit module. The center-of-gravity transferring module has a movable weight member and a transfer driving mechanism which drives movement of the weight member so as to vary a position of a center of gravity of the underwater robotic device and to control downward and upward moving directions of the underwater robotic device in the water. The propelling unit is connected with the housing unit and is electronically connected with the control unit to produce a propelling force to move the underwater robotic device forward in the water.