EP1920209B1 - Method for optimising the triggering of the firing of a weapon or an artillery gun - Google Patents

Abstract

The invention relates to a method for determining a favourable moment for triggering the firing of a weapon on a moving target. According to said method, firing commands and expected impact points (P1-P3) of a projectile and the target (2) are calculated with the aid of an algorithm, without actually triggering a firing burst. The target (2) is selected, the algorithm is activated and hypothetical data is determined. The process is aided by a graphical display (4) of the data. In the preferred embodiments, additional information is taken into account and/or is visualised for a user (5).

Description

In the fight against targets fire commands, ie, the angle of departure and the moment of firing are chosen with the intention of achieving the highest possible probability of striking. The accuracy of weapon setup, ammunition dispersion and atmospheric impact complicate this task. To counteract these disturbances, measures are taken such as, for example, calibrating in the setup procedure or measuring air pressure and temperature and wind. Added to this is the variability of the muzzle velocity, which influences the flight time of the projectile to the target. In practice, therefore, often the muzzle velocity of the projectile is measured and taken into account in the fire control. So is out of the CH 691 143 A5 a device for measuring the projectile velocity at the mouth of a weapon barrel known. This comprises two spaced apart from each other on a support tube, responsive to change in a magnetic flux sensors that are in communication with an evaluation.

Additional sources of error are in particular the unknown target movements between the time of firing the projectile and its arrival at the target. This makes it difficult to predetermine the probable position of the target at the meeting point, especially with longer flight distances of the projectile. To reduce these errors, models of the target movement are formulated and controlled with measurement data of the target in order to identify the kinematics of the target. These data are then used in the fire control to predict the target position after the expected flight time, usually extrapolated.

However, except for the radial velocity, the measurements are purely positional determinations. In the filter, the target speed and possibly the target acceleration are derived from these and used for extrapolation. The accuracy of the extrapolated data is particularly dependent on the quality of the acceleration estimate. In addition, once the target is maneuvered and the accelerations are large, it is possible that the Fire Department will refuse to fire. The known residuals of the Filters, ie, the difference between the estimate and the measurement, are therefore less suitable for this purpose because they only include the position errors to the target. A target maneuver always takes some time before the filter transforms the generated residuals into acceleration. This is spoken by the settling of the filter.

The total time delay between the target maneuver and the time of the arrival of the projectile, whose fire elements take into account these maneuvers, at the target is composed
Time delay = settling of the filter + flight time of the projectile + remaining dead times.

Other dead times are understood here as the time required for the measurement, for the data processing and transmission.

Improvements of the fire control are made by test projectiles or test shots, which can be called "closed-loop". To statistically improve the measurement results of the test projectiles, they are fired in a limited number in succession. A burst of fire, whose first shots are measured in the target, must be longer than the projectile flying time, if his last shots should profit from the corrections. Depending on the application, such measuring systems are complicated and also expensive.

From the US 4,577,962 A (which can be considered as a starting point for claim 1) a method and an arrangement for the shot control of a real or real target with real or simulated projectiles are known. In the context of a weft simulator in particular, a computer can determine in real time the derivation of the theoretical trajectory of the projectile. This is done starting from pointing elements of the weapon, the ballistics etc. of the projectile, the comparison at each instant of the position of the projectile with respect to that of a certain point of the target. The target information is determined according to the orientation of the laser beam and from the measured distance. From this, the shooting result is derived. To check his shot, the shooter or the gun can first make a fictitious shot. The computer processes the theoretical position of the simulated projectile when its reaching the target is detected and compares it with the location of the target. Then a real shot is triggered with new location data of the target, which are corrected depending on the result of the simulated shot.

The DE 11 65 459 B discloses a means for predetermining the angle or angles at which a missile must have left its starting location at a particular time to collide with a predetermined destination. For this purpose, a system is included including the tracking device for the target and the missile, which uses a working according to the sampling principle control system. The extrapolation unit of the device determines the probable trajectory of the target. The simulator simulating the trajectory may be replaced by a device indicating the actual coordinates. These are then forwarded in the form of steering commands for the missile. It is known from the cited prior art to visually represent the predicted trajectories on a reduced scale in a shooter.

The US 4,308,015 A relates to an apparatus and method for training aircraft gunners and accurate scoring. The entire fight between the aircraft is simulated and recorded.

Here, the invention takes on the task of specifying a method which assists a surgeon in the choice of the best burst of fire, especially in target maneuvers.

The problem is solved by the features of claim 1.

Advantageous embodiments are shown in the subclaims.

The invention is based on the idea to use a known calculation algorithm of a real shooting to determine the best moment of the fire triggering on moving targets, but not really trigger the fire command. This is purely hypothetical. Data is thereby determined and used by continuously calculating and collecting the fire commands and the associated prospective meeting points.

The method is based on calculating the fire commands and the expected meeting point without actually triggering the fire. The goal is sought, the algorithm is switched on and this calculates everything else hypothetical. In the algorithm can be contained thereby also the controlling of the guns as basis for the fire order.

After the calculated flight time of the hypothetical projectile, the actual target position is determined and the error distance between the target and the predicted meeting point is calculated. This gives a statement about how exactly would have been shot. Although this information is obsolete by the flight time, but can be generated continuously and provide important information about the course of the expected hit probability.

For example, the error in the target may be a minimum distance between the trajectories of the projectile and the target. If the time at the finish also plays a role, as in the case of disintegrating projectiles or grenades with a time fuse, the distance between the two at the time of disassembly is decisive. Alternatively, angle errors may be considered. Also, a suitable combination of different error definitions is conceivable, but the result is described advantageously with a scalable size.

Preference is given to representations with visible development of the errors, for example graphical curves over time, which corresponds to the correlation time of the behavior, since the data should not only provide information about the instantaneous error, but mainly allow an estimation of its behavior in the near future. For this purpose, in addition to the hypothetical data, current or quasi-current additional data are preferably made available to the operator via the display. In an automation of the method, a software consideration in the algorithm is provided, wherein the graphical representation can be maintained.

With the help of the method, a suitable measure of the hit error thus results as soon as the target approaches the meeting point calculated in advance. The calculated measure of the hit errors is graphically displayed, continuously updated and additionally made available to the surgeon or algorithm. There is no correction of the fire commands instead, rather than a costly measurement in the target area, the operator a method / presentation made available, which support him in the choice of the most favorable moment of the fire triggering.

Fig. 1

in einer blockbildartigen Darstellung die für das Verfahren benötigten Mittel,

Fig. 2

eine graphische Darstellung eines Feuerstoßes,

Fig. 3

eine Darstellung der berechneten Zielablagen in einem Zeitfenster,

Fig. 4

die Darstellung aus Fig. 3 mit einer ersten Zusatzinformation ,

Fig. 5

die Darstellung aus Fig. 3 mit einer weiteren Zusatzinformation.

Reference to an embodiment with drawing, the invention will be explained in more detail. It shows:

Fig. 1

in a block-like representation, the resources required for the process,

Fig. 2

a graphic representation of a burst of fire,

Fig. 3

a representation of the calculated target deposits in a time window,

Fig. 4

the presentation Fig. 3 with a first additional information,

Fig. 5

the presentation Fig. 3 with a further additional information.

Fig. 1 shows a marked with 1 Richtes gun, which is supplied by a computer 3 with data a target 2 fights. The computer 3 is electrically connected to the gun 1 as well as to a display device 4 for an operator 5. In the computer 3, which is usually the fire control computer, usually the target measurements are synchronized with the base clock of the fire control, so they do not coincide with the predictable hit points P1 - P3. In Fig. 2 is part of a burst of fire. A gun 1, not shown in detail, fires at regular intervals towards an approaching target 2. The flight time to the target 2 in the example shown is two to three fire cycles. Before the target files are calculated, the data is unified in time by a suitable interpolation. The gun data will be kept for at least the duration of the projectile flight. As a result of the target movement, a certain amount of time expands so that no or more target measurements occur between two shots, which is taken into account in the data processing.

Fig. 3 shows a possible application of the calculated target deposits in a time window of width T _w (T _w = time window), which can be displayed in the display 4. In this implementation, the data is graphically represented as a left-moving curve 6. The age of the most recent data equals the time of flight and is plotted on the right side of the window (f). The older data with age T _w + T _F (T _F = projectile flying time) disappear from the window on its left edge (a). The higher the curve 6, the larger would be the hit errors at the time when shooting would have been.

In this presentation, it may be seen that in (b) a favorable but short opportunity was missed, while the times in (c) and (e) would have been particularly unfavorable. But the error at the present time (f) has calmed down to a small value, so that the surgeon 5 could advantageously fire and achieve a higher accuracy.

In order to improve the obsolete data T _F , additional information is preferably integrated into the method, which gives the surgeon 5 other relevant information Of origin so that the operator 5 can determine if the time had been properly selected also from the point of view of T _F.

For this purpose, in a first variant, the operator 5 is additionally provided with data with T _F / 2 as part curve (g) graphically ( Fig. 4 ). The partial curve (g) indicates in the example shown that the current moment is not favorable, as due to the Fig. 3 was accepted as the hit errors rise again.

Another source of additional data, not shown, may be the estimated accelerations from the filter. These are updated continuously with the help of the latest target measurement.

Alternatively, the direct observation of the goal 2 offers. Before an aircraft 2 exercises a maneuver, it must change its position relative to the direction of flight. In this case, as in Fig. 5 shown, a video image of the target 2 in the display diagram of the display 4 are displayed. This also provides up-to-date data or additional information that the operator 5 takes into account in assisting him in choosing the most favorable moment of the fire triggering.

The graphs after Fig. 3 to 5 So support the surgeon 5, who interprets this displayed data so that he can conclude from the tendency of the processes on the future development of the hit.

An alternative implementation of the invention is to automate the process by a suitable algorithm to simplify the presentation of the result, for example with a lamp or to fire the fire by a fire command.

Claims (8)

1. Method for determining an advantageous moment for firing initiation at moving targets (2), wherein firing commands and hit points (P1 - P3) to be expected by a projectile with the target (2) are calculated by means of an algorithm without actually having to initiate a firing burst, for which purpose

   • the target (2) is searched for,

   • the algorithm is used, and data is determined hypothetically,

   • the actual target position is determined on the basis of the flight time, calculated in this way, of the hypothetical projectile and the miss distance between the target (2) and the previously calculated hit point (P1, P2, P3) is calculated,

   • and a statement is obtained therefrom as to how accurate the shot would have been.
2. Method according to Claim 1, characterized in that the data is displayed graphically and on a display (4).
3. Method according to Claim 2, characterized in that the graphics display is produced with visible development of the error.
4. Method according to Claim 2 or 3, characterized in that graphics curves are used over the time which corresponds to the correlation time of the response.
5. Method according to one of Claims 1 to 4, characterized in that real and current, or quasi-current, additional information can be used.
6. Method according to Claim 5, characterized in that data with T_F/2 is additionally made available graphically, as a curve element (g).
7. Method according to one of Claims 1 to 6, characterized in that estimated accelerations are used, and are continuously updated with the aid of the latest target measurement.
8. Method according to one of Claims 2 to 7, characterized in that a video image of the target (2) is overlaid on the display diagram on the display (4).

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