| 摘要 |
<p>Self-propelled hydrodynamic underwater toys with integrated propulsion mechanisms are described. In some embodiments, the propulsion mechanisms is partially or completely within an internal compartment in the toy's body. The propulsion mechanisms are adapted to be charged with a volume of fluid and to thereafter discharge the volume of fluid under pressure to propel the toy through a body of water. In some embodiments, the propulsion mechanism includes an expandable reservoir. In some embodiments, the propulsion mechanism is a replaceable propulsion mechanism. In some embodiments, the toy includes a trajectory-stabilizing structure that is adapted to impart at least one of a steering moment and a righting moment to the toy during underwater travel. The toy may be adapted to have positive, negative or neutral buoyancies, and can be adapted to maintain its buoyancy and/or its center of gravity while being propelled through a body of water by the propulsion system.</p> |
