Method of simultaneous control of aircrafts when guiding at ground-based radiation source

Abstract

FIELD: aircraft guidance.SUBSTANCE: invention relates to methods of trajectory control of aircraft guidance systems to a radiation source (RS), the location of which is determined by two-position passive angular measuring systems. The claimed method is based on the detection of a radiation source (RS) by a two-position passive angle-measuring system consisting of two aircrafts (AC) spaced apart in space at a distance from the measuring base, the organization of a continuous exchange of information between them, and the assessment of the location of the RS with a root-mean-square error determined by the root-mean-square angular errors of direction finding from the AC. At the first stage, both aircrafts are directed in the direction of the RS and the coordinates of the RS are specified using a two-position passive goniometric system by exchanging information between the aircraft. The difference in distances from the aircraft to the RS is determined; by adjusting the speed of the aircraft during their flight towards the radiation source, the same distance from each of them to the RS is achieved. If the distances are equal, the speeds of the aircraft are equalized and the distance from the aircraft to the RS is specified. At the second stage, specified points are assigned for each aircraft, based on the specified distance and the required angle “specified point for the first aircraft - RS - specified point for the second aircraft”, which ensures the smallest error in determining the location of the radiation source. Each aircraft is directed to its designated point without exchanging information between the aircrafts. Each given point is virtually moved in the direction of the RS at a speed equal to the speed of the aircraft. Aircrafts are brought to their “specified point - RS” lines, intersecting at the point where the RS is located at the required angle. At the third stage, the information exchange between the aircrafts is resumed, a two-position passive angle measuring system is organized and the coordinates of the RS are specified, the aircraft continues to fly on the RS with the flight trajectory adjusted to maintain the required angle and ensure equality of the “AC - RS” distances, which ensures the smallest error in determining the location of the RS.EFFECT: simplification of the procedure for finding signals for the trajectory of simultaneous control of aircraft, absence of restrictions on the values of the on-board bearings of the radiation source, and increase in the stealth of aircraft guidance by organizing exchange between aircraft only at the initial and final stages of guidance.1 cl, 2 dwg

Description

[0001] The proposed invention relates to the development of a method for trajectory control of aircraft guidance systems to a low-mobility ground radiation source (GRS), the location of which is determined by angular two-position passive systems (ATPS).

[0002] A gradient method for simultaneous trajectory control of aircraft is known [Anti-goniometric two-position passive airborne radio monitoring systems. Methods and algorithms for estimation and control / Ed. V.S. Verba. - Moscow: Radio Engineering. 2022. - 232 p. Pp. 60-75]. The method is based on the fact that the angles α1 and α2 of the triangulation triangle are measured on each of the aircraft.

[0003] "LA1-II-LA2" and its own rectangular coordinates, based on the measurements obtained to date, a vector of indirect measurements is formed, the components of which represent functions of the known coordinates of the aircraft, measurements of the angles α1 and α2 and the distance between the aircraft (base) R БUsing indirect measurements, estimates of the AI ​​coordinates are found that are optimal in terms of minimum root-mean-square error. Based on these estimates, signals are generated for optimal aircraft motion control, ensuring at each moment in time the minimum standard for the correlation matrix of errors of artificially generated (indirect) measurements.

[0004] The disadvantage of this method is the rather complex procedure for finding the vector field of optimal aircraft movements, and the lack of the possibility of application in situations where, at the time the AI ​​coordinates begin to be estimated, the aircraft are at a relatively small distance from each other R Б , that is, at a small angle α ИИBetween the AI's bearing lines from the aircraft, which prevents the AI's coordinates from being accurately estimated. The use of nonlinear transformations in obtaining indirect measurements imposes significant limitations on the permissible maximum bearing measurement errors (with a root-mean-square error greater than 15 arc-minutes, control failures are possible). Furthermore, implementing this method requires continuous data exchange between the aircraft at all stages regarding their own heading, onboard bearing, and their derivatives, as well as the required bearing values ​​and angular rates of the line of sight, which reduces the stealth of the aircraft's targeting of the AI.

[0005] A known method of orthogonal simultaneous control of aircraft is based on linear state models [Anti-going two-position passive airborne radio monitoring systems. Methods and algorithms for estimation and control / Ed. V. S. Verba. - M .: Radio Engineering. 2022. - 232 p. Pp. 52-57], in which the known equations of kinematic links are selected as simple models of the state of the "LA1-II" and "LA2-II" systems, which sufficiently fully reflect the relationship between the coordinates of the absolute and relative motion of the aircraft LA1, LA2 and II:

[0006]

[0007] where ϕ 1,2 - on-board bearings of the AI ​​from LA1 and LA2; ω 1,2 - angular velocities of the sighting lines “LA1-II” and “LA2-II” respectively; - the rates of change of ranges, respectively, D1 (range of "LA1-II") and D2 (range of "LA1-II"); j 1,2- lateral accelerations of aircraft1 and aircraft2, respectively, in the horizontal plane (at large distances from the target aircraft, control of the aircraft in the elevation plane is not considered), considered as controlled signals. In this method, control of aircraft equipped with onboard direction finders for determining the direction to the target aircraft and its location based on the UDPS is initially carried out in a manner that ensures increased accuracy in estimating the target aircraft's location, and only then is the task of guiding them to the target aircraft.

[0008] The disadvantage of this method is the rather complex procedure for finding the coefficients of penalties for the accuracy of operation and the magnitude of control signals that greatly affect the trajectory of the aircraft, and the lack of the possibility of using known equations of kinematic links at large angles ϕ 1,2 , since they are obtained under the assumption that the angles are small enough and therefore it can be assumed that

[0009]

[0010] Furthermore, to implement the method, it is necessary to constantly exchange data between aircraft at all stages about their own course, on-board bearing and their derivatives, as well as about the required values ​​of bearings and angular velocities of the line of sight, which reduces the stealth of aircraft guidance on AI.

[0011] The closest in essence and achieved effect (prototype) is the guidance method based on the heuristic approach [Angle-measuring two-position passive airborne radio monitoring systems. Methods and algorithms for estimation and control / Ed. VS Verba. - M .: Radio Engineering. 2022 .-- 232 p. Pp. 42-52]. The method is based on the fact that one of the aircraft (the lead aircraft) is guided to the AI, and the second aircraft (the information support aircraft) is launched to a specified point (SP) on a straight line, orthogonal to the sighting line "lead aircraft - AI", during flight the best conditions for observation are created, while the smallest error in determining the location of the AI ​​is obtained when the information support aircraft is located on this straight line at a distance to the AI ​​equal to the distance from the lead aircraft to the AI. That is, the specified point moves in time, since the lead aircraft moves in the direction of the AI.If the fastest possible approach to the perpendicular to the line of sight of the "lead aircraft-II" is required, the projection of the information support aircraft onto this perpendicular is specified as the azimuth target. To bring the information support aircraft (LA2) into the azimuth target, the control parameter is calculated using the formulas.

[0012] Δ2= k ψ (ε 2M + k a q a -ψ2), if D 2M ≥D t ,

[0013] Δ2= k ψ (ε 2M + k a q a -ψ2) + k ε (ε M -ψ2)+ k ψ (ω M -ω2), if D 2M <D t ,

[0014] where k ψ , k ε , k ω - weighting coefficients of aircraft guidance errors for aircraft 2, respectively, in course ψ2, angle ε M and angular velocity ω M line of sight of the AI ​​relative to the BT; ω2 - angular velocity of the line of sight of the AI ​​relative to the LA2; ε 2M - sighting angle of the ZT relative to the LA2; k a- weighting coefficient of the required lead angle q a ; D 2M - distance to the ZT from LA2; D t - the distance after which an additional turn of LA2 is carried out to smoothly exit to the straight line “ZT - II”.

[0015] A disadvantage of this method is the rather complex procedure of simultaneously controlling the aircraft to guide each to its designated point, where the AI's positioning error is minimized. Its applicability is limited in situations where, during the initial guidance period, the aircraft are located at relatively short distances from each other, i.e., at small α angles. ИИ, which prevents the information support aircraft from being directed to the target in a timely manner (the lead aircraft will already be in the vicinity of the AI), or requires significant differences in aircraft speeds. The need for constant exchange of data between aircraft on their own heading, onboard bearing, and their derivatives, as well as the required bearing values ​​and angular rates of the AI's line of sight, reduces the stealth of aircraft targeting.

[0016] The technical result of the invention is:

[0017] simplicity of the procedure for finding signals of trajectory simultaneous control of aircraft;

[0018] - no restrictions on the values ​​of the AI's on-board bearings;

[0019] - increasing the stealth of targeting aircraft to a radiation source by organizing data exchange between aircraft only at the initial and final stages of targeting.

[0020] The specified result is achieved by the fact that in the known method of simultaneous control of aircraft when aiming at a ground source of radiation, based on:

[0021] detection of a radiation source by a two-position passive goniometric system consisting of two aircraft spaced apart at a distance from the measuring base;

[0022] organizing continuous exchange of information between them;

[0023] estimation of the location of the radiation source with a root-mean-square error determined by the root-mean-square angular errors of direction finding from aircraft;

[0024] designating a predetermined point for the second aircraft based on maintaining a right angle between the “first aircraft - radiation source - second aircraft” and the condition that the range of the “first aircraft - radiation source” is equal to the range of the “predetermined point for the second aircraft - radiation source”;

[0025] adjusting the given point taking into account the current locations of the first aircraft and the radiation source, which ensures the smallest root-mean-square error in determining the location of the radiation source by a two-position passive angle-measuring system;

[0026] delivering the second aircraft to a specified point;

[0027] according to the invention additionally:

[0028] At the first stage, both aircraft are directed towards the radiation source and the coordinates of the radiation source are constantly refined using a two-position passive angle measuring system by exchanging information between the aircraft;

[0029] determine the difference in distances from aircraft to the radiation source;

[0030] By adjusting the speed of the aircraft during their flight towards the radiation source, the same distance from each of them to the radiation source is achieved;

[0031] if the distances are equal, the speeds of the aircraft are equalized and the distance from the aircraft to the radiation source is clarified;

[0032] at the second stage, specified points are assigned for each aircraft based on the specified distance and the required angle “specified point for the first aircraft - radiation source - specified point for the second aircraft”, which ensures the smallest error in determining the location of the radiation source;

[0033] independently direct each aircraft to its designated point without exchanging information between the aircraft, while each designated point virtually begins to move in the direction of the radiation source at a speed equal to the speed of the aircraft;

[0034] bring the aircraft to their “specified point - radiation source” lines, intersecting at the points where the radiation source is located at the required angle;

[0035] At the third stage, the aircraft fly towards the radiation source; information exchange between the aircraft is resumed, a two-position passive angle measuring system is organized, and the coordinates of the radiation source are clarified;

[0036] continue the flight of the aircraft towards the radiation source, adjusting the flight path to maintain the required angle and ensure equality of the distances “aircraft - radiation source”, which ensures the smallest error in determining the location of the radiation source.

[0037] The essence of the invention is that, in the first stage, by executing a flight of each aircraft on the RI with their speeds adjusted, the distance "Aircraft - RI" is equalized to form an isosceles triangle "Aircraft1-RI-Aircraft2" with its apex at the RI location, after which the speeds of both aircraft are equalized. In the second stage, two lines are constructed through the apex of the triangle at the required angle (in the prototype, this is an angle of 90 degrees), during the aircraft's flight along which the UDPS ensures the smallest error in determining the RI location. At a distance from the RI equal to the current range from the aircraft to the RI, a predetermined point for each aircraft is marked on each line. This point is then moved along a straight line in the direction of the RI at a speed equal to the aircraft's speed, thereby ensuring a smooth exit of the aircraft to its line along which the predetermined point moves, using the parallel approach method.

[0038] The control signals for each aircraft calculated when approaching a moving target point (actually, a straight line "ZT-AI") will be identical but opposite in sign. They are determined as in the prototype method for a single aircraft, thereby simplifying the procedure for finding simultaneous trajectory control signals for the aircraft. The use of heuristic formulas and the simultaneous turning of the aircraft in opposite directions from the direction of the AI ​​does not require significant differences in aircraft speeds and removes the upper limit on the permissible values ​​of the AI's onboard bearings.

[0039] The ability to independently control each aircraft during the targeting phase and subsequent AI flight does not require constant information exchange between the aircraft. Information exchange between the aircraft is resumed in the third phase only for the purpose of more precise determination of the AI's coordinates.

[0040] Fig. 1 shows the geometry of the relative positions of LA1, LA2 and LA2 in the azimuthal plane for the prototype method. In Fig. 1 the following are indicated: Oxz is the Cartesian coordinate system; LA2 is the location point of the radiation source; 1, 2, 3 are the trajectories of LA1, LA2 and RT, respectively; α тр - the required angle "LA1-II-LA2" to increase the accuracy of determining the coordinates of the II; ε M - the sighting angle of the IR relative to the target. Also shown for the initial moment of guidance in Fig. 1 are: ZT0 - the initial position of the given point; LA10, LA20 - the initial location points of LA1, LA2; V1, V2, ψ1, ψ2 - the velocity vectors and course angles of LA1, LA2; α 1, α2, α ии - angles of the triangulation triangle "LA1-II-LA2"; R Б - measuring base of the UDPS.

[0041] Trajectories of motion 1, 2, 3 were obtained by modeling the prototype method based on the heuristic approach [Two-position passive airborne radio monitoring systems. Methods and algorithms for estimation and control / Ed. VS Verba. - M .: Radio Engineering. 2022. - 232 p. Pp. 42-52. Method of controlling aircraft in a two-position goniometric radar system / N. O. Birina, V. I. Merkulov, O. F. Samarin, V. P. Kharkov, VS Chernov / / Radio Engineering, 2005, No. 6, pp. 66-70] with the following initial data:

[0042] -coordinates, km: II - {55; 5}, LA1 - {0; 0}, LA2- {0; 30};

[0043] - R Б = 30 km, α ии ≈ 30°;

[0044] - V1= 30 m / s, V2= 40 m / s;

[0045] - the smallest error in determining the AI ​​location is ensured at an angle of α тр =90° and the equality of the distances "LA1-II" and "LA2-II". Errors in determining the aircraft flight parameters were not taken into account during the simulation.

[0046] The following were also taken into account in the simulation: lead angle q a =5°, values ​​of the coefficients k ψ =1.5, k а =1, k ε =0, k ω =0. Coefficients k ε , k ω were taken as zero, so to ensure equality of the distances “LA1 - II” and “LA2 - II”, the second aircraft must constantly catch up with the ZT and therefore for a smooth exit to the straight line “ZT0 - II”, a formula for condition D is not required 2M <D t .

[0047] Analysis of the simulation results shows that for small initial angles α ИИ Aircraft 1 reaches the AI ​​before Aircraft 2 reaches a point on the line "3T0-AI," at which the range of "Aircraft 2-AI" is equal to the range of "Aircraft 1-AI," which fails to meet one of the conditions that ensures the smallest error in determining the AI's location. This method is feasible for large Re values ​​(commensurate with the range to the AI) or for Aircraft 2 speeds significantly exceeding the speed of Aircraft 1.

[0048] Fig. 2 shows the geometry of the relative positions of aircraft1, the reference point, and aircraft2 in the azimuthal plane for the proposed method and the stages of aircraft guidance to the reference point (separated from each other by dashed lines). In Fig. 2, the following are designated: 1, 2, 3, 4 - the trajectories of aircraft1, aircraft2, and the reference point for each of them, respectively; RP10, RP20 - the positions of the specified points of aircraft1, aircraft2 at the initial moment of time; R* Б - the measuring base of the UDPS after the completion of the first stage and the angle of its rotation α * Б relative to R Б , Ox*z* is a Cartesian coordinate system rotated relative to Oxz by an angle α * Б .

[0049] The implementation of the proposed method was simulated (Fig. 2) using the same initial data as for the prototype method.

[0050] In the first stage, upon detection of the AI, each aircraft flies in the direction of the AI. The exchange of information between the aircraft allows for the establishment of a UDPS and the continuous refinement of the AI's coordinates, as well as the exchange of aircraft flight parameters. With the initial data received, after 9 seconds, the second aircraft aligns its distance to the AI ​​with that of the first aircraft and reduces its speed to a value equal to that of Aircraft 1 (this completes the first stage of guidance). Thus, an isosceles triangle is formed: Aircraft 1 - AI - Aircraft 2, which, after rotating the coordinate system by an angle of α * Б (in the new coordinate system Ox*z*) allows the use of simple formulas from the prototype method to determine the location of the ground control point for each aircraft:

[0051] - control law for LA1,

[0052] Δ1=k ψ (ε 1M +k a q a1 -ψ1) is the control law for LA1,

[0053] Δ2=k ψ (ε 2M +k a q a -ψ2) is the control law for LA2.

[0054] Having set the required angle α тр for the vertex of the triangle "ЗТ10-ИИ-ЗТ20", provided that the median of the triangle coincides with the median of the triangle "ЛА1-ИИ-ЛА2" (the initial observation points are symmetrically removed from ЛА) and the distances "ИИ-ЗТ10", "ИИ - ЗТ20" (D 1M =D 2M ) are identical and equal to the current distance from the AI ​​to the aircraft, in the new coordinate system the equality ε will be satisfied 1M =-ε 2M , q a1 =-q a2 , ψ1=-ψ2, that is, to launch each aircraft to its own ground control point, there is no need to know the flight parameters of another aircraft.

[0055] In the second stage, using their control law, the aircraft are guided to their targeting stations, which move along their "ZT0-II" lines in the direction of the targeting station at a speed equal to the aircraft's speed. This reduces the aircraft's time to reach the targeting station's location and smoothly transitions to the "ZT0-II" line. After 16 seconds, the aircraft are guided to their "ZT0-II" lines, with the range from the aircraft to the targeting station being approximately 20 km. The second stage of guidance is complete.

[0056] At the third stage, when the aircraft are flying along their straight lines “ЗТ0-ИИ” in the direction of the AI, thereby maintaining the required angle “ЛА1-ИИ-ЛА2”, the exchange between the aircraft can be resumed to organize the UDPS and clarify the coordinates of the AI, after which the flight parameters of the aircraft are adjusted in such a way as to maintain the specified angle α тр and equality of distances from aircraft to AI, at which the UDPS ensures the smallest error in determining the location of the AI.

[0057] The technical implementation of the proposed method is generally no different from the technical implementation of the prototype method. That is, it can be implemented using known devices: onboard direction finders for the radiation source, communications equipment, and computers.

[0058] Thus, the claimed method of simultaneous control of aircraft when targeting a ground-based radiation source ensures the simplicity of the procedure for finding signals for the trajectory of simultaneous control of aircraft, the absence of restrictions on the values ​​of the on-board bearings of the radiation source, and an increase in the stealth of targeting of aircraft by organizing exchanges between aircraft only at the initial and final stages of targeting.

Claims

A method for the simultaneous control of aircraft when aiming at a ground-based radiation source, based on the detection of the radiation source by a two-position passive goniometric system consisting of two aircraft spaced apart in space by a measuring base, the organization of a continuous exchange of information between them, the assessment of the location of the radiation source with a root-mean-square error determined by the root-mean-square angular errors of direction finding from the aircraft, the assignment of a specified point for the second aircraft based on maintaining a right angle "first aircraft - radiation source - second aircraft" and the condition that the range "first aircraft - radiation source" is equal to the range "specified point for the second aircraft - radiation source", the adjustment of the specified point taking into account the current locations of the first aircraft and the radiation source,in which the smallest root-mean-square error in determining the location of the radiation source by a two-position passive angle-measuring system is ensured, the second aircraft is launched to a given point, characterized in that, in addition, at the first stage, both aircraft are directed in the direction of the radiation source and the coordinates of the radiation source are constantly specified by a two-position passive angle-measuring system through the exchange of information between the aircraft, the difference in the distances from the aircraft to the radiation source is determined, by adjusting the speeds of the aircraft during their flight to the radiation source, the same distance is achieved from each of them to the radiation source, if the distances are equal, the speeds of the aircraft are equalized and the distance from the aircraft to the radiation source is specified, at the second stage, specified points are assigned for each aircraft,based on the specified distance and the required angle "specified point for the first aircraft - radiation source - specified point for the second aircraft", in which the smallest error in determining the location of the radiation source is ensured, independently direct each aircraft to its specified point without exchanging information between the aircraft, while each specified point is virtually moved in the direction of the radiation source at a speed equal to the speed of the aircraft, the aircraft are brought to their straight lines "specified point - radiation source", intersecting at the point of location of the radiation source at the required angle, in the third stage, the aircraft fly to the radiation source, resume information exchange between the aircraft, organize a two-position passive goniometric system and specify the coordinates of the radiation source,continue the flight of the aircraft towards the radiation source, adjusting the flight path to maintain the required angle and ensuring equality of the distances “aircraft - radiation source”, which ensures the smallest error in determining the location of the radiation source.

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