A pump-less buoyancy engine for an autonomous underwater vehicle (AUV) includes a buoyancy reduction structure without a hydraulic pump for reducing the buoyancy of the AUV to cause the AUV to descend in the water; and a weight dropping structure for dropping prepackaged weights out of the AUV to cause the AUV to ascend in the water, where the AUV moves forward when descending and ascending.

A pump-less buoyancy engine for an autonomous underwater vehicle (AUV) includes a buoyancy reduction structure without a hydraulic pump for reducing the buoyancy of the AUV to cause the AUV to descend in the water; and a weight dropping structure for dropping prepackaged weights out of the AUV to cause the AUV to ascend in the water, where the AUV moves forward when descending and ascending.

A fluid medium vehicle is provided which has a main body and at least one engine attached to the main body. The engine is configured to provide thrust parallel to a thrust axis passing through the main body. A plurality of foils is moveably attached to and extends outwardly from the main body. The plurality of foils is arranged in pairs. Each pair of foils extends from the main body along opposite ends of one of a plurality of foil axes. Each foil axis is perpendicular to the thrust axis, and each foil is constructed as an independently positionable control surface and as an independently controllable propulsion device.

A fluid medium vehicle is provided which has a main body and at least one engine attached to the main body. The engine is configured to provide thrust parallel to a thrust axis passing through the main body. A plurality of foils is moveably attached to and extends outwardly from the main body. The plurality of foils is arranged in pairs. Each pair of foils extends from the main body along opposite ends of one of a plurality of foil axes. Each foil axis is perpendicular to the thrust axis, and each foil is constructed as an independently positionable control surface and as an independently controllable propulsion device.

Techniques are disclosed for providing retractable control fins on an underwater vehicle. The retractable control fins can be extended away from a main hull portion of the underwater vehicle and retracted inwards to a stowage region within the hull portion to protect the fins from damage and reduce an overall outer diameter (e.g., in the case of a cylindrical body) of the underwater vehicle. In some embodiments, the control fins are folded inwards to reduce the vehicle diameter. In other embodiments, the control fins are pulled inwards using a rotating structure designed to slide the control fins through an opening and into an inner portion of the hull to reduce the vehicle diameter. The retraction of the fins through the various retraction mechanisms reduces the envelope diameter of the underwater vehicle.

Operating at constant depth, various embodiments are provided equipped with automatic depth-control mechanisms in dynamic devices such as lures and carriers that acquire and maintain a constant target depth when pulled through a medium such as water. The depth-control mechanism incorporates a mechanical pressure measurement of depth using a bladder with changing dimensionality and mechanical coupling to a variable angle dive plane. The measured pressure is compared with the target depth pressure causing the dive plane angle to adjust and converge to an adjustable target depth with forward motion due to retrieval or trolling. The dive plane extension is optionally a variable angle lip or bill protruding from the front of the lure or a pectoral fin-like configuration. Multi-purpose carriers are provided that can perform various underwater sensing and measuring tasks. Included are systems and methods for using a lure or platform equipped with a depth-controlling device.

The present invention is a submersible device comprising a body encasing an enclosed compressible void capable of physically responding to changes in ambient pressure imparted by the device's depth underwater. This physical response to pressure changes actuates a dynamic dive plane. The forces imparted on the dive plane by the motion of the device through the water drives the device to seek, achieve and then maintain a predetermined depth. This device can be used for fishing applications and other underwater activities that benefit from dynamic depth control.

The present invention is a submersible device comprising a body encasing an enclosed compressible void capable of physically responding to changes in ambient pressure imparted by the device's depth underwater. This physical response to pressure changes actuates a dynamic dive plane. The forces imparted on the dive plane by the motion of the device through the water drives the device to seek, achieve and then maintain a predetermined depth. This device can be used for fishing applications and other underwater activities that benefit from dynamic depth control.

A body towed by a cable behind a ship and commonly referred to as a towfish, the towfish includes a structure configured to move through the water in a horizontal main direction and at least one appendage configured to generate on the towfish a downwardly directed hydrodynamic lift (P) when the towfish is moving through the water under the effect of the towing, the appendage being orientable so as to modify its lift. The towfish comprises a bracket capable of rotational movement with respect the structure about a horizontal axis perpendicular to the horizontal main direction, the cable being attached to the bracket. An orientation (γ) of the appendage, allowing it to alter the lift (P), is dependent on an angle (β) formed between the bracket and the structure about the horizontal axis.

A body towed by a cable behind a ship and commonly referred to as a towfish, the towfish includes a structure configured to move through the water in a horizontal main direction and at least one appendage configured to generate on the towfish a downwardly directed hydrodynamic lift (P) when the towfish is moving through the water under the effect of the towing, the appendage being orientable so as to modify its lift. The towfish comprises a bracket capable of rotational movement with respect the structure about a horizontal axis perpendicular to the horizontal main direction, the cable being attached to the bracket. An orientation (γ) of the appendage, allowing it to alter the lift (P), is dependent on an angle (β) formed between the bracket and the structure about the horizontal axis.