KR102038049B1 - Method and apparatus for determining location using nominal trajectory - Google Patents

Abstract

The method for determining the position of the projectile includes: obtaining an estimated trajectory of the projectile determined based on the launch position, the firing speed, and the firing direction of the projectile; obtaining position information of the projectile determined by using the plurality of radars; and The method may include updating the predicted trajectory based on an error between the predicted position of the projectile determined according to the trajectory and the position of the projectile determined by using the plurality of radars.

Description

Method and apparatus for determining location using predicted trajectory {Method and apparatus for determining location using nominal trajectory}

The present invention relates to a method and apparatus for determining a position using an expected trajectory, and provides a method and apparatus for estimating a bias of projected trajectory data of a projectile and determining a position of the projectile according to an updated predicted trajectory based on the estimated bias.

Instrumentation radars, including Doppler radars, measure the space-time position information by tracking targets, which are projectiles. To improve tracking reliability, multiple measurement radars are used to track more than one target simultaneously.

If all instrumentation radars fail to track, or a situation occurs that prevents tracking due to system performance limitations, the system operator attempts to retrace. When attempting to retrace, the instrumentation radar operator manually moves the antenna servo to explore the space or uses the positional information on the nominal trajectory obtained prior to the weapon system flight test.

In general, if the target tracking fails, the operator attempts to transmit to the antenna to the standby position and then acquire and track. Since the flight trajectory and the predicted trajectory of the actual weapon system are different, the target may not be captured even if the transmission is directed toward the measurement radar antenna to the standby position. If you don't catch it, it's actually hard to track any more.

The present invention provides a method and apparatus for determining position using predicted trajectories.

The technical problem to be achieved by the present embodiment is not limited to the technical problems as described above, and other technical problems may be inferred from the following embodiments.

According to an aspect, a method of determining a position of a projectile includes: obtaining an estimated trajectory of a projectile determined based on a launch position, a launch speed, and a launch direction of a projectile; obtaining position information of the projectile determined using a plurality of radars And updating the predicted trajectory based on the error between the predicted position of the projectile determined according to the predicted trajectory and the position of the projectile determined using the plurality of radars.

According to another aspect, an apparatus for positioning a projectile includes a communication unit, a memory, and a processor, wherein the processor acquires an expected trajectory of the projectile determined based on the launch position, the launch speed, and the launch direction of the projectile, and generates a plurality of radars. The location information of the projectile determined by using the target may be obtained, and the predicted trajectory may be updated based on an error of the projected position determined by the predicted trajectory and the position of the projectile determined by using the plurality of radars.

1 is a diagram illustrating a radar tracking interworking system.
2 is a block diagram illustrating a projectile positioning device according to an exemplary embodiment.
3 is a flowchart illustrating a method of determining a position of a projectile by the projectile positioning device according to an exemplary embodiment using predicted trajectory data.
4 is a flowchart illustrating a method of updating the predicted trajectory data by estimating a bias of the predicted trajectory according to an exemplary embodiment.

Hereinafter, only exemplary embodiments will be described in detail with reference to the accompanying drawings. The following examples are intended to embody the technical idea, but do not limit or limit the scope. From the detailed description and examples, what can be easily inferred by the experts in the relevant technical field is interpreted as belonging to the scope of rights.

As used herein, the term “consisting of” or “comprising” should not be construed as including all of the various elements, or steps, described in the specification, and some or some of them may be included. Should not be included, or should be construed to further include additional components or steps. In addition, terms such as “unit” and “module” described in the specification mean a unit that processes at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software.

In addition, terms including ordinal numbers, such as “first” or “second”, as used herein may be used to describe various components, but these terms may distinguish one component from another or It can be used for convenience.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a radar tracking interworking system.

To track the projectile 30, an interlocking network between the plurality of radars 10 and 20 may be established. For example, the plurality of radars 10, 20 may comprise metrology radars including Doppler radars. The plurality of interlocking radars 10 and 20 simultaneously tracks the projectile 30. In addition, in order to stably estimate the projectile 30, the plurality of radars 10 and 20 may transmit and receive tracking information to each other in real time through an interlocking network.

Referring to FIG. 1, the first radar 10 and the second radar 20 establish an interlocking network to track the projectile 30. The first radar 10 and the second radar 20 may transmit / receive the tracking data in real time through the microwave tower 50. For example, when the first radar 10 fails to track the projectile 30, the tracking data is interlocked from the second radar 20 through the microwave tower 50, and the projectile 30 is restarted based on this. Can be traced

The predicted trajectory data of the projectile 30 is data regarding a trajectory of the projectile 30 estimated based on environmental information such as the launch position, the launch speed and the launch direction of the projectile 30, and the wind direction and intensity. The position of the projectile 30 on the expected trajectory at a particular point in time is called a radar designation point.

When all the radars 10 and 20 fail to track the projectile 30, the radar is directed to the standby position at a specific point in time, so that the tracer 30 can be retraced from the specific point in time.

However, if a bias occurs between the expected trajectory and the actual trajectory, retrace may fail. Therefore, the estimated trajectory may be updated by estimating the bias between the predicted trajectory and the actual trajectory, and the probability of retrace may be increased based on the updated predicted trajectory.

2 is a block diagram illustrating a projectile positioning device according to an exemplary embodiment.

The projectile position determining apparatus 200 may include a memory 210, a communication unit 220, and a processor 230. It is apparent to those skilled in the art that only essential components of the present embodiment are shown in FIG. 2, and that other general purpose configurations may be further included.

The projectile position determining apparatus 200 may store data about the predicted trajectory and position information of the projectile determined using a plurality of radars in the memory 210. Also, the projectile positioning device 200 may store estimated position information of the projectile on the expected trajectory. For example, the projectile positioning device 200 may store coordinate information corresponding to the expected position of the projectile on the expected trajectory. In addition, the projectile position determining apparatus 200 may store data about a tracking trajectory, which is a trace of the position of the projectile determined in the memory 210 using a plurality of radars. In addition, the projectile position determining apparatus 200 may store coordinate information corresponding to the position of the projectile on the tracking trajectory.

The term "memory" should be interpreted broadly to include any electronic component capable of storing electronic information. The term memory refers to random access memory (RAM), read-only memory (ROM), non-volatile random access memory (NVRAM), programmable read-only memory (PROM), erase-programmable read-only memory (EPROM), electrical And may refer to various types of processor-readable media, such as erasable PROM (EEPROM), flash memory, magnetic or optical data storage, registers, and the like. If the processor can read information from and / or write information to the memory, the memory is said to be in electronic communication with the processor. The memory integrated in the processor is in electronic communication with the processor.

The projectile positioning device 200 may communicate with an external device through the communication unit 220. For example, the projectile position determining apparatus 200 may obtain position information of the projectile by at least one of the first and second radars through the communication unit 220. In addition, the projectile position determining apparatus 200 may obtain the expected trajectory data of the projectile through the communication unit 220. As another example, the projectile position determining apparatus 200 may determine the predicted trajectory using the processor 230 and obtain data on the predicted trajectory.

The predicted trajectory data is the predicted trajectory data of the projectile based on the launch position, the launch speed, and the launch direction of the projectile. The predicted trajectory data may include location information of the projectile according to a predetermined time interval from the launch time of the projectile.

In addition, the predicted trajectory data may be predicted by further considering external factors such as wind direction and wind strength.

The expected trajectory obtained prior to the weapon system flight test may be given in latitude, longitude, and altitude generally corresponding to the projectile's position relative to the elapsed time from the time of launch.

The processor 230 may perform coordinate transformation on the predicted trajectory data into a coordinate system defined based on the first radar. For example, in a coordinate system defined based on the first radar, a specific position may be specified according to a range, azimuth, and elevation. As another example, the processor 230 may obtain the predicted locus data, which are coordinate-converted into a coordinate system defined based on the first radar, from the external device through the communication unit.

The processor 230 may obtain an expected trajectory of the projectile determined based on the launch position, the launch speed, and the launch direction of the projectile.

The processor 230 may acquire the expected trajectory data from the external device through the communication unit 220. As another example, the processor 230 may determine an expected trajectory of the projectile.

The processor 230 may perform coordinate transformation on the predicted trajectory data with a coordinate system defined based on the first radar. For example, in a coordinate system defined based on the first radar, a specific position may be specified according to a range, azimuth, and elevation. As another example, the processor 230 may obtain, from the external device, the predicted locus data that is coordinate-converted into a coordinate system defined based on the first radar through the communication unit 220.

The processor 230 may obtain information about the position of the projectile determined using the plurality of radars. The plurality of radars may include a first radar and a second radar that communicate with each other by transmitting and receiving tracking information.

The processor 230 may receive location information of the projectile determined by the second radar. In addition, the processor 230 may obtain a tracking trajectory, which is a trace of the position of the projectile determined by the second radar, from the position information of the received projectile.

For example, when the tracking of the projectile fails, the first radar may acquire tracking trajectory data of the projectile tracked by the second radar through linkage with the second radar. In addition, coordinate transformation may be performed on the coordinate data included in the tracking trajectory data of the second radar obtained through linkage from the coordinate system based on the second radar to the coordinate system based on the first radar. The first radar may track the projectile based on the tracking trajectory data on which the coordinate transformation is performed.

If tracking fails for both the first radar and the second radar, the processor 230 may acquire data of the tracking trajectory of the projectile tracked by the second radar until the second radar fails to track. As described above, the processor 230 coordinates from the coordinate system on the basis of the second radar to the coordinate system on the basis of the first radar with respect to the coordinate data included in the data of the tracking trajectory of the second radar obtained through linkage. You can perform the conversion.

As another example, the processor 230 may obtain data about a tracking trajectory of the projectile tracked by the first radar. When the first radar fails to track, the processor 230 may acquire tracking trajectory data of the first radar acquired until a time when the first radar fails to track.

The processor 230 may update the predicted trajectory based on the difference between the predicted position of the projectile determined according to the predicted trajectory and the position of the projectile determined by using the plurality of radars.

The processor 230 may estimate an error bias that is a difference between the tracking trajectory and the expected trajectory. The error bias may be estimated using a positional error of the projectile, which is a difference between the tracking coordinates of the projectile on the tracking trajectory of the second radar and the expected coordinates of the projectile on the expected trajectory corresponding to the tracking coordinates.

The processor 230 may estimate the error bias of the expected trajectory by comparing the tracking coordinates of the projectile on the tracking trajectory of the second radar with the expected coordinates of the projectile on the predicted trajectory at mutually corresponding time points. The difference between the trajectory and the predicted trajectory of the projectile after the second radar fails to track may be estimated based on the difference between the track and the predicted trajectory of the projectile until the second radar fails to track. For example, the difference between the position of the projectile at the reference point immediately after the point at which the second radar fails tracking and the position on the predicted trajectory is the position of the projectile on the tracking trajectory at the reference point just before the failed point of tracking and the projected position of the projectile on the expected trajectory. It can be estimated in consideration of the position error of. Further, as time passes, the position error between the tracking position of the projectile on the tracking trajectory and the expected position of the projectile on the expected trajectory may increase or decrease.

The processor 230 calculates the error bias between the trajectory of the projectile and the expected trajectory after the second radar fails to track by further considering the change rate of the position error, the change rate of the position error, and the change rate of the position error at the reference point immediately before the tracking failure point. It can be estimated.

In addition, the processor 230 may model the error bias quadratic with respect to time. The processor 230 may determine the coefficients in the quadratic equation of time with respect to the error bias based on the position error, the rate of change of the position error, and the rate of change of the position error change rate.

The processor 230 may update the expected trajectory based on the estimated error bias. For example, the estimated trajectory may be updated by adding the estimated error bias to the estimated position coordinate of the projectile on the predicted trajectory at each reference time point.

As another example, when the tracking trajectory data of the projectile tracked by the first radar is used, the first radar is not included in the tracking except that coordinate transformation is not performed to a coordinate system based on the first radar. The error bias can be estimated in the same manner using the tracking trajectory data up to the point of failure.

The processor 230 may track the projectile according to the updated expected trajectory using the first radar. The first radar may be previously directed to a standby position on the updated predicted trajectory to track the projectile from the time when the projectile is captured at the standby position. The waiting position may indicate an expected position of the projectile on the updated predicted trajectory at any point after the current time point, that is, at the start of tracking or the start of retrace.

The processor 230 may obtain an expected trajectory of the projectile determined based on the launch position, the launch speed, and the launch direction of the projectile.

The processor 230 may acquire the expected trajectory data from the external device through the communication unit 220. As another example, the processor 230 may determine an expected trajectory of the projectile.

The processor 230 may perform coordinate transformation on the predicted trajectory data with a coordinate system defined based on the first radar. For example, in a coordinate system defined based on the first radar, a specific position may be specified according to a range, azimuth, and elevation. As another example, the processor 230 may obtain, from the external device, the predicted locus data that is coordinate-converted into a coordinate system defined based on the first radar through the communication unit 220.

The processor 230 may obtain information about the position of the projectile determined using the plurality of radars. The plurality of radars may include a first radar and a second radar that communicate with each other by transmitting and receiving tracking information.

The processor 230 may receive location information of the projectile determined by the second radar. In addition, the processor 230 may obtain a tracking trajectory, which is a trace of the position of the projectile determined by the second radar, from the position information of the received projectile.

For example, when the tracking of the projectile fails, the first radar may acquire tracking trajectory data of the projectile tracked by the second radar through linkage with the second radar. In addition, coordinate transformation may be performed on the coordinate data included in the tracking trajectory data of the second radar obtained through linkage from the coordinate system based on the second radar to the coordinate system based on the first radar. The first radar may track the projectile based on the tracking trajectory data on which the coordinate transformation is performed.

If tracking fails for both the first radar and the second radar, the processor 230 may acquire data of the tracking trajectory of the projectile tracked by the second radar until the second radar fails to track. As described above, the processor 230 coordinates from the coordinate system on the basis of the second radar to the coordinate system on the basis of the first radar with respect to the coordinate data included in the data of the tracking trajectory of the second radar obtained through linkage. You can perform the conversion.

As another example, the processor 230 may obtain data about a tracking trajectory of the projectile tracked by the first radar. When the first radar fails to track, the processor 230 may acquire tracking trajectory data of the first radar acquired until a time when the first radar fails to track.

The processor 230 may update the predicted trajectory based on the difference between the predicted position of the projectile determined according to the predicted trajectory and the position of the projectile determined by using the plurality of radars.

The processor 230 may estimate an error bias that is a difference between the tracking trajectory and the expected trajectory. The error bias may be estimated using a positional error of the projectile, which is a difference between the tracking coordinates of the projectile on the tracking trajectory of the second radar and the expected coordinates of the projectile on the expected trajectory corresponding to the tracking coordinates.

The processor 230 may estimate the error bias of the expected trajectory by comparing the tracking coordinates of the projectile on the tracking trajectory of the second radar with the expected coordinates of the projectile on the predicted trajectory at mutually corresponding time points. The difference between the trajectory and the predicted trajectory of the projectile after the second radar fails to track may be estimated based on the difference between the track and the predicted trajectory of the projectile until the second radar fails to track. For example, the difference between the position of the projectile at the reference point immediately after the point at which the second radar fails tracking and the position on the predicted trajectory is the position of the projectile on the tracking trajectory at the reference point just before the failed point of tracking and the projected position of the projectile on the expected trajectory. It can be estimated in consideration of the position error of. Further, as time passes, the position error between the tracking position of the projectile on the tracking trajectory and the expected position of the projectile on the expected trajectory may increase or decrease.

The processor 230 calculates the error bias between the trajectory of the projectile and the expected trajectory after the second radar fails to track by further considering the change rate of the position error, the change rate of the position error, and the change rate of the position error at the reference point immediately before the tracking failure point. It can be estimated.

In addition, the processor 230 may model the error bias quadratic with respect to time. The processor 230 may determine the coefficients in the quadratic equation of time with respect to the error bias based on the position error, the rate of change of the position error, and the rate of change of the position error change rate.

The processor 230 may update the expected trajectory based on the estimated error bias. For example, the estimated trajectory may be updated by adding the estimated error bias to the estimated position coordinate of the projectile on the predicted trajectory at each reference time point.

As another example, when the tracking trajectory data of the projectile tracked by the first radar is used, the first radar is not included in the tracking except that coordinate transformation is not performed to a coordinate system based on the first radar. The error bias can be estimated in the same manner using the tracking trajectory data up to the point of failure.

The processor 230 may track the projectile according to the updated expected trajectory using the first radar. The first radar may be previously directed to a standby position on the updated predicted trajectory to track the projectile from the time when the projectile is captured at the standby position. The waiting position may indicate an expected position of the projectile on the updated predicted trajectory at any point after the current time point, that is, at the start of tracking or the start of retrace.

As used herein, the term “processor” should be interpreted broadly to include general purpose processors, central processing units (CPUs), microprocessors, digital signal processors (DSPs), controllers, microcontrollers, state machines, and the like. In some circumstances, a “processor” may refer to an application specific semiconductor (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), or the like. The term "processor" refers to a combination of processing devices such as, for example, a combination of a DSP and a microprocessor, a combination of a plurality of microprocessors, a combination of one or more microprocessors in conjunction with a DSP core, or a combination of any other such configuration. May be referred to.

3 is a flowchart illustrating a method of determining the position of a projectile by the projectile position determining apparatus 200 according to an exemplary embodiment.

In operation 310, the projectile positioning apparatus 200 may obtain an expected trajectory of the projectile determined based on the launch position, the launch speed, and the launch direction of the projectile.

The projectile position determining apparatus 200 may obtain predicted trajectory data from an external device through the communication unit 220. Alternatively, the projectile position determining apparatus 200 may determine the predicted trajectory of the projectile using the processor 230.

The projectile position determining apparatus 200 may perform coordinate transformation on the predicted trajectory data with a coordinate system defined based on the first radar. For example, in a coordinate system defined based on the first radar, a specific position may be specified according to a range, azimuth, and elevation. As another example, the projectile position determining apparatus 200 may obtain the predicted trajectory data, which is coordinate-converted into a coordinate system defined based on the first radar through the communication unit 220, from an external device.

In operation 320, the projectile position determining apparatus 200 may obtain information about the position of the projectile determined using the plurality of radars. The plurality of radars may include a first radar and a second radar that communicate with each other by transmitting and receiving tracking information.

The projectile position determining apparatus 200 may receive the position information of the projectile determined by the second radar. Also, the projectile position determining apparatus 200 may obtain a tracking trajectory, which is a trace of the position of the projectile determined by the second radar, from the position information of the projectile received.

For example, when the tracking of the projectile fails, the first radar may acquire tracking trajectory data of the projectile tracked by the second radar through linkage with the second radar. In addition, coordinate transformation may be performed on the coordinate data included in the tracking trajectory data of the second radar obtained through linkage from the coordinate system based on the second radar to the coordinate system based on the first radar. The first radar may track the projectile based on the tracking trajectory data on which the coordinate transformation is performed.

If tracking of both the first radar and the second radar fails, the projectile positioning device 200 may acquire data of the tracking trajectory of the projectile tracked by the second radar until the second radar fails to track. . As described above, the projectile position determining device 200 is based on the first radar in the coordinate system on the basis of the second radar with respect to the coordinate data included in the data of the tracking trajectory of the second radar obtained through linkage. Coordinate transformation can be performed by the coordinate system.

As another example, the projectile positioning device 200 may obtain data on a tracking trajectory of the projectile tracked by the first radar. When the first radar fails to track, the projectile positioning device 200 may obtain tracking trajectory data of the first radar acquired until the first radar fails to track.

In operation 330, the projectile positioning apparatus 200 may update the predicted trajectory based on the difference between the predicted position of the projectile determined according to the predicted trajectory and the position of the projectile determined by using the plurality of radars.

The projectile positioning device 200 may estimate an error bias that is a difference between the tracking trajectory and the expected trajectory. The error bias may be estimated using a positional error of the projectile, which is a difference between the tracking coordinates of the projectile on the tracking trajectory of the second radar and the expected coordinates of the projectile on the expected trajectory corresponding to the tracking coordinates.

The projectile positioning device 200 may estimate the error bias of the predicted trajectory by comparing the coordinates of the projectile on the tracking trajectory of the second radar and the predicted coordinates of the projectile on the predicted trajectory at mutually corresponding time points. The difference between the trajectory and the predicted trajectory of the projectile after the second radar fails to track may be estimated based on the difference between the track and the predicted trajectory of the projectile until the second radar fails to track. For example, the difference between the position of the projectile at the reference point immediately after the point at which the second radar fails tracking and the position on the predicted trajectory is the position of the projectile on the tracking trajectory at the reference point just before the failed point of tracking and the projected position of the projectile on the expected trajectory. It can be estimated in consideration of the position error of. Further, as time passes, the position error between the tracking position of the projectile on the tracking trajectory and the expected position of the projectile on the expected trajectory may increase or decrease.

The projectile position determining device 200 further considers the positional error, the rate of change of the position error, and the rate of change of the position error change rate at a reference point immediately before the point of failure of tracking, between the trajectory of the projectile and the predicted trajectory after the second radar fails to track. Error bias can be estimated.

In addition, the projectile positioning device 200 may model the error bias in quadratic with respect to time. The projectile positioning device 200 may determine the coefficients based on the position error, the rate of change of the position error, and the rate of change of the position error in the quadratic equation of the time for the error bias.

The projectile positioning device 200 may update the expected trajectory based on the estimated error bias. For example, the estimated trajectory may be updated by adding the estimated error bias to the estimated position coordinate of the projectile on the predicted trajectory at each reference time point.

As another example, when the tracking trajectory data of the projectile tracked by the first radar is used, the first radar is not included in the tracking except that coordinate transformation is not performed to a coordinate system based on the first radar. The error bias can be estimated in the same manner using the tracking trajectory data up to the point of failure.

The projectile positioning device 200 may determine the position of the projectile according to the updated predicted trajectory using the first radar. The first radar may be previously directed to a standby position on the updated predicted trajectory to track the projectile from the time when the projectile is captured at the standby position. The waiting position may indicate an expected position of the projectile on the updated predicted trajectory at any point after the current time point, that is, at the start of tracking or the start of retrace.

FIG. 4 is a flowchart illustrating a method in which the projectile position determining apparatus 200 updates the predicted trajectory data by estimating a bias of the predicted trajectory according to an exemplary embodiment.

In operation 410, the projectile position determining apparatus 200 may perform coordinate transformation on the predicted trajectory data into a coordinate system based on the first radar.

As described above, the coordinates of the projectile in the predicted trajectories included in the predicted trajectory data are represented by latitude, longitude, and altitude according to elapsed time from the launch time.

), 방위각(

), 고각(

)으로 나타낼 수 있다. 특정 발사 시점으로부터 경과한 시간에

에 따른 예상 궤적 상의 발사체의 위치를 다음과 같이 나타내도록 한다.The position estimating apparatus which intends to track or re-track the projectile using the first radar performs coordinate transformation on the predicted trajectory of the predicted trajectory data into a coordinate system based on the position of the first radar, thereby providing a distance (

), Azimuth (

), Elevation (

) At the time that elapsed from a specific launch

The position of the projectile on the expected trajectory according to

는 시간 순서에 따라 k번 째로 발사체의 예상 위치 좌표가 표시되는 시간이다. 이를 k 번째 기준 시점이라고 지칭한다.At this time, when the position on the projected trajectory of the projectile is indicated by the coordinates, the position cannot be represented by the coordinates at all successive times, and therefore, the position must be represented by the corresponding position coordinates every predetermined time interval.

Is the time at which the predicted position coordinates of the projectile are displayed in the kth order according to the time sequence. This is called the k th reference time point.

는 시간 순서에 따라 k번 째로 발사체의 예상 위치 좌표가 표시되는 시간이다.Similarly, when tracking a projectile using a radar, the tracked position of the projectile can be represented at the same time interval,

Is the time at which the predicted position coordinates of the projectile are displayed in the kth order according to the time sequence.

In operation 420, the projectile position determining apparatus 200 may coordinate transform the tracking trajectory data of the second radar into a coordinate system based on the first radar.

As described above with reference to FIG. 3, the first radar and the second radar may form an interworking network to transmit and receive tracking data in real time.

), 방위각(

), 고각(

) 나타내어지는 추적 궤적 데이터를 획득할 수 있다.The projectile positioning device 200 performs coordinate transformation on the coordinate system based on the first radar from the tracking trajectory data of the projectile represented by the distance, azimuth, and elevation in the coordinate system based on the second radar. Distance (

), Azimuth (

), Elevation (

) Can be obtained tracking trace data.

에 따른 발사체의 추적 위치는 다음과 같은 수학식으로 나타내어질 수 있다.Elapsed time from launch when included in acquired trace trajectory data

The tracking position of the projectile according to can be represented by the following equation.

In operation 430, the projectile position determining apparatus 200 compares the predicted trajectory data with the coordinate transformation and the tracking trajectory data.

For example, the projectile positioning device 200 uses the predicted trajectory data and the tracking trajectory data to determine a position error that is a difference between the position of the projectile on the tracking trajectory and the position of the projectile on the predicted trajectory at a corresponding reference time point. It can be represented by the formula.

은 다음 수학식들에 따라 계산된다.At this time,

Is calculated according to the following equations.

In operation 440, the projectile positioning apparatus 200 may estimate a bias between the projectile trajectory and the predicted trajectory data.

이 마지막 추적 위치에 대응하는 기준 시점일 수 있다. 예를 들어, 제 2 레이더가 추적에 실패한 경우, 추적 실패 시점의 직전 기준 시점은

이다.It can be assumed that the tracking trajectory data includes the tracking position coordinates of the projectile at M reference time points. In other words, according to the elapsed time after launch,

It may be a reference time point corresponding to this last tracking position. For example, if the second radar fails to track, the reference point immediately before the track fails

to be.

에서 추적 궤적상의 위치 오차는 다음과 같이 나타낼 수 있다.At this time, as described above in step 440 at the last reference point, the last reference point

The position error on the tracking trajectory can be expressed as

(

에서, 거리, 방위각, 고각 각각에 대한 위치 오차의 1차 미분의 근사 값은 다음과 같인 나타낼 수 있다.Also, just before

In Eq, an approximate value of the first derivative of the position error for each of the distance, azimuth, and elevation may be expressed as follows.

은 다음과 같은 수학식에 따라 계산될 수 있다.E.g,

May be calculated according to the following equation.

에서, 거리, 방위각, 고각 각각 위치 오차의 2차 미분의 근사 값

은 다음과 같인 나타낼 수 있다.Also, any reference point

Approximation of the second derivative of the position error for distance, azimuth, and elevation respectively

Can be expressed as:

각각은 다음과 같은 수학식에 따라 계산될 수 있다.E.g,

Each may be calculated according to the following equation.

In addition, it is possible to obtain an average of an approximation of the second derivative of the error component at N (N <M) reference time points immediately before the failure of the position error.

By using the average of the obtained position error, the approximate value of the first derivative of the position error, and the approximate value of the second derivative of the position error, the error bias according to the elapsed time can be expressed as follows.

The reason why the average is used is to reduce the effects of noise generated because the radar moves to the motor.

In operation 450, the projectile positioning apparatus 200 may update the predicted trajectory data of the projectile using the estimated bias.

The projectile positioning device 200 may update the predicted trajectory by adding a bias to a position on the predicted trajectory at each time point.

For example, the projected position of the projectile over time on the updated predicted trajectory may be represented as follows.

은 다음 수학식들에 따라 계산된다.At this time, the distance, azimuth, and elevation which are the estimated position coordinates of the projectile on the updated predicted trajectory

Is calculated according to the following equations.

The projectile position determining device 200 may attempt to retrace by inputting the updated predicted trajectory to the radar operating computer. The radar operating computer can act as a kind of virtual radar.

Each step described with reference to FIG. 4 may be performed by the projectile positioning device 200 illustrated in FIG. 2 using the processor 230 of FIG. 2.

The above description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the invention is indicated by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the invention. do.

Claims (6)

In the method of determining the position of the projectile,
Obtaining an expected trajectory of the projectile determined based on the launch position, the launch speed, and the launch direction of the projectile;
Obtaining location information of the projectile determined using a plurality of radars; And
Updating the predicted trajectory based on an error between the predicted position of the projectile determined according to the predicted trajectory and the position of the projectile determined using the plurality of radars.
Including,
The plurality of radars include a first radar and a second radar to communicate with each other by transmitting and receiving the position information of the projectile,
Acquiring position information of the projectile,
Receiving location information of the projectile determined by the second radar until a point at which the second radar fails to track;
The updating of the expected trajectory may include:
Estimating an error bias that is a difference between a tracking trajectory that is a trace of the position of the projectile determined by the second radar obtained from the received positional information of the projectile, and the expected trajectory;
The error bias is,
And estimated using a position error of the projectile which is a difference between a position coordinate of the projectile on the tracking trajectory and an expected position coordinate of the projectile on the predicted trajectory. delete delete The method of claim 1,
Estimating the error bias,
Estimating the error bias based on the position error, the rate of change of the position error, and the rate of change of the rate of change of the position error. The method of claim 4, wherein
Estimating the error bias,
Modeling the error bias quadratic with respect to time,
And a coefficient of the quadratic equation over time is determined based on the rate of change of the position error, the rate of change of the position error, and the rate of change of the position error. In the positioning device of the projectile,
Communication unit;
Memory; And
Includes a processor,
The processor,
Obtain an estimated trajectory of the projectile determined on the basis of the launch position, the launch speed, and the launch direction of the projectile, obtain position information of the projectile determined using a plurality of radars, and predict the projectile determined according to the expected trajectory Update the expected trajectory based on an error of a position and a position of the projectile determined using the plurality of radars,
The plurality of radars include a first radar and a second radar to communicate with each other by transmitting and receiving the position information of the projectile,
The processor,
Until the point at which the second radar fails to track, receiving position information of the projectile determined by the second radar, and receiving the position information of the projectile determined by the second radar obtained from the position information of the projectile received. Estimating an error bias that is a difference between the tracer tracking trajectory and the expected trajectory,
Wherein the error bias is estimated using a position error of the projectile which is a difference between a position coordinate of the projectile on the tracking trajectory and an expected position coordinate of the projectile on the predicted trajectory.

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