Submersible vehicle
A submersible vehicle having an outer hull which defines a hull axis and appears substantially annular when viewed along the hull axis, the interior of the annulus defining a duct which is open at both ends so that when the vehicle is submerged in a liquid, the liquid floods the duct. The vehicle further comprising means for rolling the vehicle about the hull axis. A buoyancy control system may be provided, and the outer hull may be swept with respect to the hull axis. Various methods of deploying and using the vehicle are described.
1. A submersible vehicle having an outer hull which defines a hull axis and appears substantially annular when viewed along the hull axis, the interior of the annulus defining a duct which is open at both ends so that when the vehicle is submerged in a liquid, the liquid floods the duct; and a twin thrust vector propulsion system comprising one or more pairs of propulsion devices, each pair comprising a first propulsion device pivotally mounted at a fixed position on the interior of the annulus on a first side of the hull axis, and a second propulsion device pivotally mounted at a fixed position on the interior of the annulus on a second side of the hull axis opposite to the first propulsion device wherein each propulsion device generates a thrust vector which points in a direction which can be varied by pivoting the device, and wherein the propulsion devices can be pivoted between a first configuration in which their thrust vectors point in the same direction to provide a thrust force to propel the vehicle forward and along the hull axis, and a second configuration in which their thrust vectors point in different directions to cause the vehicle to roll around the hull axis.
2. A vehicle according to claim 1 wherein the propulsion devices are positioned in the duct.
3. A method of operating a submersible vehicle, the vehicle comprising an outer hull which defines a hull axis and appears substantially annular when viewed along the hull axis, the interior of the annulus defining a duct which is open at both ends so that when the vehicle is submerged in a liquid, the liquid floods the duct, the method comprising: submerging the vehicle in a liquid whereby the liquid floods the duct, and rolling the vehicle about its hull axis through a plurality of revolutions by the action of a propulsion system, the method further comprising pulsing on the propulsion system as the vehicle rolls about its hull axis, the propulsion system being pulsed on over a limited arc of said roll of the vehicle about its hull axis so that the vehicle is moved in a plane that lines normal to the hull axis.