Underwater vehicle with a shaped charge with variable effect

Description

[0001] The invention relates to a watercraft with a shaped charge. Such watercraft are regularly used for clearing objects, especially mines.

[0002] Clearing a mine is usually achieved by detonating the explosives inside the mine with an external charge. A shaped charge is typically used for this purpose. However, it is important to note that the explosives used in a mine can be difficult to ignite, and only the detonator itself contains highly explosive material. It is therefore necessary to achieve a high energy input into the mine's explosives within a certain volume. For this reason, shaped charges are typically used to detonate the explosives in a mine.

[0003] In a maritime environment, due to the arrangements in three-dimensional space, as well as within the element area and other bodies present in the surrounding area, it is not always possible to approach the mine freely. As a result, the distance between the watercraft used for mine clearance and the mine depends on the mission. This results in the problem that optimal energy transfer into the mine's explosive is not always possible, as water and other barrier layers, such as the mine casing, have a weakening effect on the effect of the shaped charge.

[0004] When clearing a mine, it is essential to know whether the object to be detonated has been safely defused. The most reliable and fastest way to ensure this is to detonate the mine during clearance. The parameters for clearing should therefore be such that any existing explosives are detonated safely and reliably.

[0005] From DE 36 09 864 B3 a shaped charge projectile for combating underwater targets is known, wherein an extendable arrangement is arranged in front of the shaped charge.

[0006] From DE 27 45 744 A1 a hollow explosive charge device for underwater use with a spacer chamber with an inflatable element is known.

[0007] A warhead for fin-stabilized projectiles and missiles is known from DE 28 57 576 C1.

[0008] A warhead is known from EP 2 410 283 A2.

[0009] EP 2 489 588 A1 discloses an unmanned underwater vehicle with exchangeable bodies that can be fixed to it.

[0010] The object of the invention is to provide a watercraft in which an optimal energy input into the explosive can be achieved regardless of the achievable distance between the watercraft and a mine.

[0011] This object is achieved by a watercraft having the features specified in claim 1. Advantageous further developments emerge from the subclaims, the following description and the drawing.

[0012] The watercraft according to the invention has a shaped charge. In In the direction of action of the shaped charge, a gas chamber adjoins the shaped charge. The gas chamber is important because a plasma jet forms in this gas chamber when the shaped charge is ignited. The shape of the plasma jet and its speed are influenced by the length of the gas chamber in the direction of action.

[0013] According to the invention, the gas space is variable in length in the direction of action of the shaped charge.

[0014] By varying the length of the gas chamber, the shape and speed of the plasma jet can be precisely adjusted to the current requirements. The longer the gas chamber, the narrower and faster the plasma jet becomes. A shorter gas chamber produces a wider plasma jet with a lower speed.

[0015] Since the energy input into the explosive is proportional to the speed of the jet and the cross-sectional area of ​​the jet at the location of the explosive, the energy loss between the watercraft and the mine can be optimized by varying the plasma jet. To do this, the length of the gas space is maximized when the distance between the watercraft and the mine is short, thus creating a comparatively fast plasma jet. This fast plasma jet suffers greater attenuation in the water, but because the distance is short, the energy losses at a short distance are lower than with a wide, slow plasma jet. If the distance between the watercraft and the mine is longer, however, the gas space is shortened, creating a comparatively slow plasma jet. This is slower and therefore less attenuated by the surrounding water. This means that a greater amount of energy reaches the mine over a greater distance.

[0016] According to the invention, the shaped charge is arranged so that it can move parallel to the direction of action of the shaped charge. Particularly preferably, the direction of action of the shaped charge is parallel to the longitudinal direction of the vessel. Moving the shaped charge allows for particularly simple modification of the gas space. In particular, the outer hull of the vessel represents the natural boundary of the gas space and thus firmly defines the gas space at one end.

[0017] In a further alternative embodiment of the invention, the shaped charge is fixed, and a movable boundary wall is arranged between the shaped charge and the outer hull of the vessel, so that the length of the gas space between the shaped charge and the boundary wall can be adjusted by moving the boundary wall. This embodiment is preferred if the boundary wall has at least one further degree of freedom, for example, can be tilted in one or two axes. This allows for further design options for the plasma jet.

[0018] In a further embodiment of the invention, the shaped charge is movable by means of a threaded rod. The advantage of this embodiment is its comparatively robust design.

[0019] In a further embodiment of the invention, the length of the gas space can be varied between 0.1 and ten times the diameter of the shaped charge. Particularly preferably, the length of the gas space can be varied between 0.5 and seven times the diameter of the shaped charge. Further lengthening the gas space does not lead to further acceleration, so larger sizes are of no use. Since a mine always has a wall, a minimum length is also useful, as the effective distance between the shaped charge and the explosive charge can therefore never be zero.

[0020] According to the invention, the watercraft has a distance detection device, wherein the distance detection device can detect the distance between the watercraft and an object arranged in front of the watercraft, in particular a mine. The watercraft has a movement device for changing the length of the gas space. Furthermore, the watercraft has a control device, wherein the control device is designed to determine the optimal length of the gas space from the detected distance between the watercraft and the object arranged in front of the watercraft and to control the direction of movement for adjusting the length of the gas space. For example and in particular, the distance detection device comprises a sonar or an optical sensor such as a camera or a laser-based distance meter.In particular, the control device is designed to shorten the length of the gas space the greater the distance between the watercraft and the object.

[0021] In a further embodiment of the invention, the watercraft is an unmanned underwater vehicle. Particularly preferably, the watercraft is a remotely controlled unmanned underwater vehicle. With remote control, the shaped charge can be safely and reliably triggered by an operator at a safe location and based on recognized protocols. Alternatively, the watercraft can also be an autonomous unmanned underwater vehicle, although this is not without its problems due to the autonomous detonation of an explosive charge.

[0022] The watercraft according to the invention is explained in more detail below using an embodiment shown in the drawing. Fig. 1 Cross section

[0023] In Fig. 1A watercraft according to the invention is shown by way of example. A shaped charge 20 can be moved by means of a threaded rod 30. This varies the distance between the shaped charge 20 and the casing 40, where a gas space is located. The watercraft 10 can be moved via a propeller 70. For this purpose, the watercraft preferably has a battery 50 and a motor 60. Using a sonar 90 as a distance detection device, the distance to an object can be determined, and thus the optimal position of the shaped charge 20 can be determined and controlled via a control device 80. Reference symbol

[0024] 10Vessel 20Shaped charge 30Threaded rod 40Hull 50Battery 60Motor 70Propeller 80Steering device 90Sonar

Claims

1. Watercraft (10) with a hollow charge (20) and a gas space adjoining the hollow charge (20) in the direction of action of the hollow charge (20), the gas space being variable in length in the direction of action of the hollow charge (20), characterized in that the hollow charge (20) is arranged such that it can be moved parallel to the direction of action of the hollow charge (20), the watercraft (10) having a distance-detecting device, the distance detection device being able to detect the distance between the watercraft (10) and an object located in front of the watercraft (10), the watercraft (10) having a movement device for changing the length of the gas space, the watercraft (10) having a control device (80), wherein the control device (80) is designed to determine the optimum length of the gas space from the detected distance between the watercraft (10) and the object located in front of the watercraft and to control the direction of movement and the setting of the length of the gas space.

2. A watercraft (10) according to claim 1, characterized in that the hollow charge (20) is movable by means of a threaded rod (30).

3. A watercraft (10) according to any of the preceding claims, characterized in that the length of the gas space between 0.1 times and ten times the diameter of the hollow charge (20) is variable.

4. A watercraft (10) according to one of the preceding claims, characterized in that the watercraft (10) is an unmanned underwater vehicle.