KR20020076005A - Process for the target-related correction of a ballistic trajectory - Google Patents

Abstract

PURPOSE: A trajectory modifying method according to a target is provided to capture the target precisely, and to hit the mark accurately by decreasing the trajectory with increasing aerodynamic braking moment. CONSTITUTION: A fire control computer(14) decides azimuth orientation of a projectile(17), elevation(15) and propellant charge power according to direction and range(11) from a cannon to a target(13). The calculated trajectory(18) is decided by a sensor and the computer considering external factors, and compared with measured trajectory to estimate instantaneous actual trajectory. The initialization point is decided corresponding to the estimated trajectory, and the projectile is induced to the transitional trajectory by increasing the drag coefficient. The trajectory measured on a satellite support of the quasi-ballistic projectile is modified by turning the projectile into the transitional trajectory with increasing aerodynamic drag coefficient according to estimated target layoff.

Description

How to modify ballistics by target {PROCESS FOR THE TARGET-RELATED CORRECTION OF A BALLISTIC TRAJECTORY}

The present invention relates to the method described in the preamble of claim 1.

Such a method is known from WO 98/01719, which uses a satellite navigational apparatus on a projectile to determine the trajectory that is currently in progress, and target this trajectory. Compared to an optimized trajectory, when a point on the trajectory derived from this comparison is reached, a method of releasing an aerodynamic braking device to modify the target accuracy of subsequent trajectories to the maximum possible. In practice, however, many external influencing factors still act on the trajectory even after the release of the braking means that even if the trajectory is modified, the operative mechanism of the projectile does not strike the target correctly. .

EP 0 138 942 B1 contains an elevation and charge for ballistic trajectory aiming the target from the cannon, for example by radar, and slightly off the target in a fire control computer. It is known to determine the instantaneous position of the projectile relative to the artillery by radar immediately after determining the projectile launch speed from the barrel. The comparison between this instantaneous position and the reference position according to the calculated trajectory is used to determine the actual expected target layoff, and the final step is from this comparison when the aerodynamic braking effect should be actuated on the projectile. The resulting layoff is reduced from the target by extending the braking flap or blowing off the aerodynamic projectile tip to appropriately reduce the residual trajectory according to the new aerodynamic conditions. In addition, the method compares the actual trajectory with a specific abnormal trajectory in order to determine the braking time, and when the initialisation time of the braking means causes an error due to external influence, interference occurs and still acts on the modified trajectory. Of course, the target layoff occurs.

This modification of the braked transition from the initial trajectory path to the optimized trajectory after the apogee allows the target sensor, control system and projectile to automatically target-seeking final approachflight. It is substantially less expensive than installing a regulating loop. On the other hand, given the fact that the speed of the projectile is particularly fast in the early stages, the method of determining the actual trajectory path from the initial instantaneous point on the measured trajectory is very inaccurate. The actual flight trajectory, however, must be very accurate in order to provide optimal timing of the braking operation after the origin, to reduce trajectory to lower the degree of scattering in the target area. Another problem with ground-supported processes is the reliability of the communication link transmitting the braking triggering time, or the high speed of the projectile, which in some cases interferes with wireless communication. It is in the braking command itself from the launch control computer to the projectile because it can fly a portion of its trajectory in the ionizing atmospheric shell.

In view of these factors, the object of the present invention is self-reliant but still inaccurate in practical situations, using the aforementioned general method, which reduces trajectory by increasing the aerodynamic braking moment, thereby making the target substantially more effective. It is developed to capture precisely.

In the present invention, the object of the present invention is achieved by carrying out the steps of the essential method described in the independent claims.

The method according to the invention thus measures holding points by reducing the far greater longitudinal scattering of projectiles fired in trajectory or quasi-ballistically, which are essentially known as described above, in comparison to the transverse scattering. It is based on the concept of first placing it behind the target position, and then shortening the trajectory. However, the artillery's laying effect occurs after braking the projectile, taking into account the current error budget on the shortest ballistic trajectory, so that the transitional trajectory can accurately guide the projectile onto the target. Wherein, according to the present invention, the predetermined error range is determined from a comparison with the theoretically expected trajectory for a predetermined error parameter as long as possible to the braking moment along the trajectory.

The projectile may not only be, for example, a drive-less projectile or a missile fired from a mortar or howitzer, but also to initially increase the range along a semi-ballistic trajectory. It can be an artillery rocket with an acting rocket motor. The actual transition trajectory the projectile has moved from its initial trajectory by the aerodynamic braking effect is the lowest or shortest (minimum) trajectory and the highest or longest (maximum) trajectory of the current scatter fan or range. Located in between, it can in principle be converted to the shortest trajectory, ie a trajectory directly directed to the target by means of braking action.

Determining current trajectories does not include methods for determining trajectories from guns, which are inevitably virtually inaccurate and technically unreliable due to interference effects. On the contrary, as is known, the initiation point for braking control is determined by the projectile itself without steering depending on the data link with the ground station. To this end, the projectile has a satellite receiving device which determines the actual initial trajectory. ) Is also provided. Because it can vary from the general types of situations described above, braking control is not triggered when reaching a point on the ballistic, and in the present invention the initial ballistic curve is the theoretical firing curve over the longest possible time period for as many ballistic points as possible. (launch curve). Current deviation impacts identified from this firing curve, system control determinants and preferably, furthermore, as in DE 41 20 367 A1, for example by combining further measurements by sensor means from projectiles and / or ground, for example Use as a basis to determine the parameters of. This parameter is influenced not only by the direction and intensity of the wind, especially at different heights, but also by the influence of the intensity of the firing or firing charge, which varies depending on, for example, the error range of the launching device (known cross and height direction aiming inaccuracy of the gun) and the surrounding environment. Included. As mentioned above, the braking time is estimated by pre-calculating actually accurate information about the interference effect still continuing on the transition trajectory the projectile follows after the release of the braking means by a general external-ballistic approach. By correcting this, it is possible to correct in advance. In order to obtain as much information as possible to determine the current margin of error, the braking time is delayed as much as possible. Thus, in the end, it is not determined by the launch of the projectile, but by the remaining flight time theoretically achieved on the target. Thus, inversely with time, it is determined by the inverse relationship with the temporary movement along the so-called trajectory.

In order to reduce the flight time for communicating with the navigation satellite from the projectile as far as possible, in particular, a trajectory that can be calculated for a range of instantaneous errors already known to the projectile, so as to initiate measures as soon as possible after the projectile has been launched, i.e. Information regarding the current ideal ballistics and the satellite communications expected from the ballistics are provided. In this way, very quickly accessing at least some of the navigational satellites on the horizon from the projectile provides reliable information about the actual trajectory, that is to quickly obtain the deviation of this trajectory from the predetermined trajectory by calculation and thus the actual present from this information. The effect of error can be inferred.

The greater the number of current trajectory points that can be measured on the projectile by satellite navigation, the more accurately the trajectory is determined until starting braking control past the origin, thus predicting the ray from conventional measurement moments that communicate with the projectile at launch. Off can be determined more accurately on the projectile. This ensures that the ideal initial point for initiation of braking, i.e., entry into the transition trajectory determined by the new aerodynamic conditions, is appropriately from the actual trajectory, which is too far from the minimum accurately targeted trajectory, depending on the remaining flight time into the target area. Can be accurately predetermined. On the other hand, since the possible delayed braking time can be determined accurately, satellite tracking can be used to update information about the actual trajectory within a time immediately approaching the operating point for braking control, i.e., a point that can be extended correspondingly long beyond the origin. In this way, the actual trajectory affected externally can be determined to be closest to the target and thus provide information about the interference effect until it is close to the target. At this time, on the actual trajectory that is determined very accurately by the continuous updating of the error effects presently present, the final initialization point entering the braking transition trajectory in order to approach the minimum trajectory is urgent, and the structurally predetermined braking operation is exemplified. For example, it can be triggered by extending the braking member or by blowing the aerodynamic projectile tip, thereby reaching the target with very high confidence in the final approach flight phase on the minimum trajectory or trajectory very close to the target.

In order to minimize the complexity and expense of the operation of determining the optimum (most delayed) braking trigger point on the projectile, placed between the maximum trajectory and the minimum trajectory and also outside the pure ballistic parabola due to wind or other interference effects, for example. The trajectory coordinates of the actual trajectory arrangement to be obtained are preferably stored, for example, in the form of a look-up table from a launch control computer in the processor on the projectile, and also in an ideal order, ie the remaining of each trajectory of the arrangement. The most delayed initialization point over the transition time can be stored as the trigger curve. For the current actual trajectory within an array that is currently very accurately determined from the satellite route, only the instantaneous intersection of the current flying trajectory with the trigger curve still needs to be expected to trigger the braking effect so that it can accurately transition to the minimum trajectory aimed at the target. There is.

Further alternatives and developments as well as other features and advantages of the present invention from the description and the claims of a preferred embodiment for carrying out the method according to the invention disclosed with reference to the drawings schematically depicted in a simplified and limited summary of essential parts only. It will be clearly understood.

1 is a longitudinal cross-sectional view illustrating the principle of firing a ballistic projectile at the final approach phase from an artillery, with the flying face directed from the actual ballistic towards the target along a minimum trajectory, i.e., a target-hit braking trajectory. The initial point of incidence is determined through satellite-supported ballistic determination actions on the projectile.

The azimuth orientation, elevation 15 and propulsion charge power of the projectile 17 trajectory relative to the target area, depending on the preset direction and range 11 from artillery 12 to the target 13. (propellent charge power) (so-called theoretical muzzle velocity 16) is determined at the launch control computer 14. The calculated shot trajectory 18 is, after the apogee, a predetermined error range within a predetermined longitudinal scattering or dispersion 23 of the area around the target 13 to be actually captured, the so-called possible collision point within the target area. Transition to trajectory 20 between minimum trajectory 21 and maximum trajectory 22 for. Due to inaccurate elevation 15, gun muzzle velocity 16 that is substantially different from the preset value, and system related and usage related error effects such as wind influence 19, which differ in strength and direction depending on height, The trajectory 20 does not actually coincide with the trajectory following from the trajectory parabola calculated for the trajectory 18 and gradually deviates slightly from the trajectory. Since the trajectory 20 cannot be elongated by the aerodynamic braking effect and can only be shortened, the projectile 17 can be provided with a braking surface that can be extended by, for example, a flat projectile front member that can be folded, pivoted or released. Reference may also be made to braking sails which are provided with known aerodynamic braking devices which may be included, or which may be radially unfolded for shortening the trajectory according to DE 3 608 109 A1.

For certain braking systems 26 and certain interference effects, it is ideal for the remaining flight time to the target 13 from which the projectile traverses from the actual trajectory 20 to the transition trajectory 25 with a minimum trajectory ( An initialization time 24 is associated with the actual trajectory 20, which can gradually approach 21 and precisely deviate precisely to finally reach the target 13 theoretically and accurately. The earlier the initialization point 24 occurs in correspondence with the actual trajectory 20, the farther the trajectory 20 can be further from the target 13 on the target area plane without braking correction interference, i. 20) can be higher. This can be represented as a trigger curve 28 (as can be seen in the figure) for the possible actual trajectory 20 arrangement, where the ideal initialization point 24 order is somewhat pivoted over the set of curves of the actual trajectory 20. Therefore, the actual trajectory 20 between the minimum trajectory and the maximum trajectory 21-22 intersects once each. Various interference effects (such as wind data 19) may be parameters for differently inclined ballistic arrays 20 sets and / or differently extended trigger curves 28 sets.

As such, the immediate achievement of the ideal initialization point 24 for a given firing trajectory 18 under current interference conditions can be predicted in practice because the actual trajectory 20 of the disturbance can be known accurately.

The action of determining the current actual trajectory 20 (from which the initialization point 24 can be obtained) is carried out on the projectile itself over the longest possible flight path section, so that as much as possible into the trajectory 20 from the trajectory 18 is possible. Detect the actual effect of the error effect. The ballistic determination operation is performed by receiving satellite support, i.e., location information from the navigation satellites 27 currently detected on the projectile 17, based on generally known ballistic data, such as from satellite navigation, by different systems of the local satellite. do. For this purpose, the spin-stabilised projectile 17 is rotated in opposition to the spin and can be received directly without interference by enclosing the projectile 17 on its outer circumferential surface, ie EP 0 840 393 A2. It is desirable to provide antenna member scanning that can eliminate interference ground reflections for satellite radiation, as disclosed in detail below.

Switching to satellite 27 as soon as possible, i.e. close connection of the actual ballistic coordinates initialized as early as possible can be achieved to determine the actual ballistic 18 and the ballistics 20 obtained therefrom. The expected value for the position is also given to the projectile 17 from the launch control computer 14 at the time of launch for a launch trajectory 18 predetermined by the calculation, which serves as a reference after launch of the continuously updated projectile. . In addition, the order of the initialization points 24 for the disturbed arrangement of possible actual trajectories 20 is stored as an uninterrupted set of trigger curves 28 of the projectile 17 processor to anticipate the initialization points 24.

Considering the influence of the current interference on the actual trajectory 20, which is actually accurately determined by satellite navigation, when reaching the stored ideal initialization point 24, the braking device 26 is activated and the projectile from the previous actual trajectory 20 Leave to the transition trajectory 25 towards the target 13.

Thus, in order to significantly reduce the inevitable ballistic scattering or dispersion of projectiles projected to the target area without the technical cost of automatic target tracking control, the minimum ballistics 21 can be used to substantially improve target accuracy. To the maximum trajectory 22 of the overall margin of error by positioning through a pre-identified target position 13 taking into account external influence parameters such as the headwind 19 which is dependent on the error range and the height on the actual trajectory 20. All actual ballistics 20 are located behind the target position 13. The lowering of the projectile 17 into the target area is shortened from the actual actual trajectory 20 to the minimum trajectory 21, ie the target position 13, by the aerodynamic braking effect. For this purpose, the achievement of an optimum initialization point 24, which depends on the theoretical residual flight time for the aerodynamic braking device on the projectile 17, is determined on the actual trajectory 20 by measures according to the invention, (20) is continuously measured by satellite navigation over the longest possible distance just in front of the intersection of the predetermined trigger curve 28 according to environmental factors, and consequently includes all actual error effects. Thus, the actual approach to the intersection of the trigger curve 28, i.e., the order of the optimal initialization points 24-24 for the actual trajectory 20/20 arrangement is set, from which the braking transition trajectory 25 is adjusted. Through the target position 13 to match the minimum trajectory 21.

See description above.

Claims (4)

Depending on the expected target layoff, the ballistics measured on the ballistic or quasi-ballistic projectile's satellite support by increasing the projectile's aerodynamic drag coefficient and turning the projectile at the initial trajectory into a steeper transition trajectory to the target. In a way to modify, Considering the influence of external interference on the ballistic shape, the actual ballistics beyond the target are predicted and determined by comparing the measured ballistics with the ballistics determined by the sensor means and / or the calculation, and for the expected actual ballistics, Modifying the trajectory for turning to a precisely targeted minimum trajectory by increasing the drag coefficient by determining an initialization point as close to the target as possible in consideration of the external interference effect. The method according to claim 1, wherein for the actual trajectory arrangement between the minimum trajectory to the expected target and the maximum trajectory beyond the target depending on the error, a trigger curve for a series of initialization points is stored in the projectile and from the ongoing satellite navigation. And determining a momentary intersection point of the trigger curve with the measured actual trajectory to trigger a braking device. 3. A method according to claim 1 or 2, wherein a set of interference dependent curves for actual ballistic and / or trigger curves are stored in the projectile. 4. A modification according to claim 1, 2 or 3, characterized in that the point of initiation of the projectile is predetermined when firing into the expected actual ballistic, in accordance with communication with a navigation satellite for making ballistic measurements. Way.