Aircraft laser guidance irradiation method based on double-machine cooperative background

Abstract

The present application relates to a kind of aircraft laser guidance irradiation method based on the background of double-machine cooperation, belong to aircraft multi-machine cooperative route planning technical field.The method uses one aircraft to launch laser guided weapon in launching basket, another aircraft uses the flight route that Dubins maneuver path is combined with the linear motion around target, with certain occupancy, the double-machine cooperative strategy of laser guidance irradiation, the performance constraint of laser irradiator and aircraft is modeled, the search range of each variable is determined, the laser irradiation route of aircraft is generated by traversing search to each variable.The method provides a kind of aircraft laser guidance irradiation method based on the background of double-machine cooperation in combination with various constraint conditions existing in use process, establishes a kind of laser guidance irradiation route calculation model, solves the cooperative occupancy problem and time synchronization problem of each aircraft laser guidance irradiation in double-machine cooperation process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aircraft multi-machine cooperative route planning, and particularly relates to an aircraft laser guidance irradiation method based on double-machine cooperative background. BACKGROUND

[0002] Laser guidance is an advanced guidance technology, and laser guidance weapons usually have high hit rates in practical applications. The basic principle of laser guidance is to use a laser to emit a laser beam to irradiate a target, and a laser receiving device mounted on a projectile body receives the laser signal reflected by the target, calculates the degree of deviation of the projectile body from the reflected laser beam, continuously adjusts the flight trajectory, and makes the warhead advance along the reflected laser, and finally hits the target. At present, most laser irradiation devices are installed on the ground, vehicles, ships or aircraft.

[0003] Based on the characteristics of laser guidance weapons, the general use method is to install a laser irradiation device on an aircraft, which is responsible for both launching and irradiation, that is, the aircraft launches and irradiates. However, under the current background of multi-agent cooperation, in order to fully develop the combat potential of the aircraft, multi-machine cooperative operation has become a future development trend, especially in some specific environments. The combat mode of launching weapons by one aircraft and laser guidance irradiation by another aircraft often has greater flexibility and maneuverability.

[0004] At present, most of the related research on double-machine cooperation is for non-laser-guided conventional weapons, and the research on double-machine cooperative laser guidance irradiation is very little. The current manned double-machine cooperative laser guidance irradiation mainly includes two strategies. The first strategy is that one aircraft circles in a certain airspace, and when another aircraft launches a laser guidance weapon, the aircraft flies towards the target and performs laser guidance irradiation. This method cannot guarantee that after the weapon is launched, the aircraft can complete the irradiation task on the target according to the irradiation requirements on time when the weapon seeker is turned on. The second strategy is the companion mode, that is, two aircrafts fly together at a certain safe distance. When one aircraft launches a weapon, the other aircraft launches a laser according to the irradiation requirements. This method is essentially similar to the combat mode of single-aircraft launching and irradiating, which is not conducive to the development of the maneuverability of double machines. In actual use scenarios, the positions of various aircrafts are usually dispersed and carry their own tasks, so they may not have the conditions for double-machine companion flying. The above two strategies usually master the timing and route of double-machine cooperation by the pilot according to subjective experience in the process of completing laser guidance irradiation, and human factors have a greater impact on the combat effect.

[0005] For laser guided weapons, the time precision requirement is high, the irradiation intensity and angle requirement is strict, and the subjective experience of human beings often cannot meet the demand of cooperative combat. Therefore, when two aircrafts cooperatively carry out laser guided irradiation, the process of dropping and irradiation needs to be quantitatively analyzed, so as to ensure the combat effect of the two aircrafts. The aircraft responsible for the irradiation task needs to comprehensively consider the constraint conditions such as laser guided irradiation time, angle, distance and the like, and formulate a simple and feasible irradiation route. In addition, the calculation method of the two-aircraft cooperative irradiation route needs to fully consider the possible situations in the actual use scene, and formulate a two-aircraft cooperative route which can convert the distributed combat of multiple aircrafts into cooperative combat. SUMMARY

[0006] (1) Technical problem to be solved

[0007] The technical problem to be solved by the present application is how to solve the cooperative occupation problem and time synchronization problem of laser guided irradiation of each aircraft in the two-aircraft cooperative process.

[0008] (2) Technical solution

[0009] In order to solve the above technical problem, the present application provides a kind of aircraft laser guided irradiation method based on two-aircraft cooperation, comprising the following steps:

[0010] Step 1, determine input and output data

[0011] The input data are: (1) the dropping machine: the position of the far boundary and the near boundary of the basket, the current position of the latitude and longitude, and the speed information, the attack scheme, wherein the connecting line of the far and near boundary points of the basket points to the target; (2) the latitude and longitude of the target position; (3) the current position of the latitude and longitude and the speed information of the irradiation machine; the output data are the key route points of the flight route of the dropping machine and the irradiation machine;

[0012] Step 2, determine the related model and parameter definition used

[0013] Firstly, the related model used includes a laser irradiation time calculation model; secondly, the basic coordinate system used is a north-east coordinate system with the target as the origin, in addition, the ground speed coordinate system is to rotate the basic coordinate system around the celestial coordinate axis by a certain angle, so that the north coordinate axis of the basic coordinate system points to the ground speed direction of the aircraft, therefore, the input and output data need to be converted between coordinate systems; the occupation angle θ is defined as the included angle formed by the connecting line from the entering position p0 of the irradiation machine to the target to the far boundary point of the basket;

[0014] Then, the threshold value Δt of the time difference of the dropping machine and the irradiation machine flying from the current position to the far boundary point of the basket and the entering position p0 of the irradiation machine respectively is determined max ;

[0015] Step 3, according to the laser emitter irradiation range data on the illuminator, a piecewise polynomial function fitting method is used to establish the irradiation range constraint model of the laser emitter α max = f(β), where α max is the irradiable pitch angle boundary value of the laser emitter relative to the illuminator body spherical coordinate system when the laser emitter points to the target, β is the azimuth angle of the target in the illuminator body spherical coordinate system; in addition, the maximum irradiation distance r_laser max of the laser emitter is determined.

[0016] Step 4, based on steps 1 to 2, the entering position calculation model of the illuminator is established.

[0017] Step 5, based on steps 1 to 3, the calculation model of the Dubins path and the straight flight irradiation path around the target of the illuminator is established.

[0018] Step 6, determine the dimensions of the search and their boundary values

[0019] The illuminator needs to perform path search when calculating the irradiation route, so the dimensions of the search include the cooperation direction of the illuminator relative to the delivery machine inDir∈{-1,1}, the distance between the illuminator and the target, i.e. the machine-target distance dis PT ∈[dis min ,dis max ], the turning direction dir∈{-1,1}, and the turning central angle Then the search step of dis PT and is determined respectively.

[0020] Step 7, after determining the above models and related parameters, the Dubins path of the delivery machine from the current position to the far boundary point of the delivery basket and the time t base needed for flight along the Dubins path can be calculated by the delivery machine.

[0021] Step 8, the delivery machine calculates the laser on-off machine time t s , t e according to the attack scheme, target position, delivery basket far and near boundary position, etc. The flight time t far of the delivery machine from p near is calculated, and then the laser irradiation time calculation model is used to calculate the laser on-off machine time t fly , t far , t near , t s_far , t e_far , t s_near , t e_near of the delivery machine when delivering the laser guided weapon at the far boundary point p fly and the near boundary point p far of the delivery basket respectively.

[0022] Step 9, the release machine will t s , t e , t base , the release basket far boundary point position and other information to the irradiation machine, and output the release machine from the current waypoint to the release basket far boundary point Dubins path waypoint information;

[0023] Step 10, the irradiation machine traverses the search flight path in turn. The release basket far boundary point and the target position are converted to the base coordinate system, and then the irradiation machine is matched in the direction inDir, the machine-eye distance dis PT , the turning direction dir, and the turning center angle Each search dimension is traversed in turn, and the specific search process is as follows:

[0024] (1) The first layer search dimension is inDir; first determine the value of the irradiation machine matching direction inDir, and then traverse the search dis max from dis min to dis PT , and then determine the entry position p0 of the irradiation machine according to the entry position calculation model of step 4;

[0025] (2) According to the Dubins path length and speed of the irradiation machine, the Dubins path of the irradiation machine from the current position to the p0 position and the flight time is calculated to determine whether the absolute error of t base is less than or equal to Δt max ; if yes, the next step is executed, otherwise continue to traverse the values of dis PT and inDir, return to step (1) to recalculate p0;

[0026] (3) Traverse the values of dir and in turn, and calculate the irradiation path flying around the target straight line according to the calculation model in step 5; if the irradiation segment in the flight path meets the irradiation condition constraint, the above search process is ended, and the next step is executed, otherwise no solution is output;

[0027] Step 11, the irradiation machine outputs the flight path of cooperative irradiation; at this time, the irradiation machine has found an irradiation path that meets the irradiation condition constraint in the search process, so according to the Dubins path of the irradiation machine from the current position to the p0 position and the irradiation path flying around the target straight line, the key waypoint of the irradiation machine from the current position to the irradiation end point is output.

[0028] Preferably, in step 4, assuming that the matching direction of the illuminator relative to the delivery machine in the base coordinate system is inDir, the value of inDir is -1 indicating that the illuminator is matched on the right side of the delivery machine, and the value of inDir is 1 indicating that the illuminator is matched on the left side of the delivery machine, and the far boundary point of the delivery basket is p far , then the calculation formula of the north coordinate n0 and the east coordinate e0 of the entering position p0 of the illuminator is as follows:

[0029]

[0030]

[0031] dis PT is the distance between the illuminator and the target, i.e., the machine-target distance, is the azimuth angle of the point p far relative to the target in the base coordinate system.

[0032] Preferably, in step 5, the specific flight route of the illuminating path flying around the target is as follows: assuming that the aircraft flies at a constant speed during the flight, the aircraft flies at the maximum roll angle γ max left or right from the starting position p0, and the central angle of the turning circle is After the turning is completed, the straight and level flight phase begins; in the flight process, taking the moment when the starting position p0 is as the reference point of the relative time, if the laser on and off times of the laser-guided weapon are t s and t e respectively, then the laser on and off points in the flight route can be determined according to the relationship among the distance, time and speed, wherein the laser on point can be located in the turning phase or the straight and level flight phase, and the laser off point is located in the straight and level flight phase; the specific calculation process is as follows:

[0033] Assuming that the starting position of the illuminator in the ground speed coordinate system is p0(x0, y0, z0), taking p0 as the reference point of the relative time, the ground speed is v, the height is h, and the maximum roll angle of the aircraft is γ max , then the minimum turning radius of the aircraft can be calculated according to the steady disc formula , wherein g is the gravitational acceleration, if the turning direction is dir, the value of dir is 1 indicating right turning, and the value of dir is -1 indicating left turning, and the central angle of the turning circle corresponding to the turning end point p1 of the aircraft is , then the following position information calculation process is performed:

[0034] The longitudinal coordinate x1, the lateral coordinate y1, and the speed direction of the turning end point p1 are calculated as follows:

[0035]

[0036]

[0037]

[0038]

[0039] If t s < t1, the laser start point p s is located in the turning phase, and the longitudinal coordinate x s , the lateral coordinate y s , and the aircraft fly to the laser start point p s corresponding to the turning center angle The calculation formula is as follows:

[0040]

[0041]

[0042]

[0043] If t s > t1, the laser start point p s and the laser shutdown point p e are located in the straight flight phase, and the lateral and longitudinal coordinates of the two positions can be calculated using the following formula, where t = t s or t e :

[0044]

[0045]

[0046] Then, based on p1, p s , p e , the target origin coordinates, and the aircraft roll angle at the corresponding position, the coordinate values (α, β, r) of the target in the irradiation aircraft body spherical coordinate system at each position are obtained; whether the key waypoints located in the irradiation flight segment simultaneously satisfy the constraints of the irradiation requirements is judged as follows:

[0047] α max = f(β)

[0048] α≤α max

[0049] r≤r_laser max

[0050] In the constraint relationship: according to the coordinates of the target and the coordinates of the irradiation machine at different positions, the actual azimuth angle β, the actual pitch angle α and the machine-eye distance r of the target in the irradiation machine body spherical coordinate system are calculated, and then the maximum pitch angle α that can irradiate the target at the azimuth angle β is calculated max , and whether α and r can satisfy the inequality constraint is judged;

[0051] If the constraint is satisfied, the p0, p s , p e position information in the ground speed coordinate system is converted to the basic coordinate system and output for use by the outside world; if the above constraint is not satisfied, the position of p0 or the turning center angle is changed, and the above position information calculation process is repeatedly continued until a solution is obtained.

[0052] Preferably, the Dubins path of the irradiation machine is the shortest feasible path between two directional points in the plane under the constraint of the minimum turning radius.

[0053] Preferably, in step 7, assuming that the line connecting the far boundary point and the near boundary point of the release basket points to the target, the current position of the machine and the latitude and longitude of the far boundary point of the release basket are converted to the basic coordinate system, and each waypoint in the Dubins path and the path length s are calculated according to the coordinates of the two points and the corresponding speed and direction base , and then the time required for flight according to the Dubins path is calculated according to the ground speed v throw of the release machine

[0054] Preferably, in step 8, p far is the reference point of the laser on-off time output by the release machine, and the laser on-off time output by the release machine is calculated according to the following formula:

[0055] t s =min(t s_far ,t s_near +t fly )

[0056] t e =max(t e_far ,t e_near +t fly )。

[0057] The application also provides a system for implementing the method.

[0058] The application also provides an aircraft multi-machine cooperative route planning method based on the method.

[0059] (Three) beneficial effects

[0060] The application adopts one aircraft to drop a laser guided weapon in a basket, and another aircraft adopts a flight route combining Dubins maneuvering path and target linear motion, to perform a double-aircraft cooperative strategy of laser guided irradiation with a certain occupation, models performance constraints of the laser irradiator and the aircraft, determines the search range of each variable, and generates a laser irradiation flight path of the aircraft through traversal search of each variable. BRIEF DESCRIPTION OF DRAWINGS

[0061] Fig. 1 is a double-aircraft cooperative strategy diagram in the aircraft laser guided irradiation method based on double-aircraft cooperation of the application;

[0062] Fig. 2 is a calculation flowchart of the dropping aircraft in the aircraft laser guided irradiation method based on double-aircraft cooperation of the application;

[0063] Fig. 3 is a calculation flowchart of the irradiation aircraft in the aircraft laser guided irradiation method based on double-aircraft cooperation of the application. DETAILED DESCRIPTION

[0064] In order to make the purpose, content and advantages of the application more clear, the specific embodiments of the application are described in further detail below in combination with the drawings and examples.

[0065] The application provides an aircraft laser guided irradiation method based on double-aircraft cooperation, which generates two cooperative flight paths of laser guided irradiation under the scene of double-aircraft cooperation, so that one aircraft flies from the current position to the specified position to drop a laser guided weapon, and another aircraft cooperates with the laser guided weapon to perform laser guided irradiation with a certain occupation and flight route, to ensure that the aircraft (irradiation aircraft) reaches the irradiation position on time when the laser seeker of the laser guided weapon is started after the laser guided weapon is dropped, and the target is continuously irradiated by the laser irradiator until the weapon hits the target.

[0066] The method determines a laser-guided illumination strategy of dual aircraft cooperation, that is, one aircraft as a launching aircraft flies to the target from the current position, and launches the laser-guided weapon in the designated launching basket, and the other aircraft as an illumination aircraft flies to the side of the launching aircraft in a Dubins path, the velocity direction of the entering position p0 of the illumination aircraft is directed to the target, and the connecting line from p0 to the target and then to the far boundary point of the launching basket forms a certain occupation angle θ; when the illumination aircraft reaches the occupation, the illumination aircraft performs the illumination in a flight route of linear motion around the target. The process of calculating the cooperative flight route of the dual aircraft is as follows: after the launching aircraft calculates the laser switch-on and switch-off time and other information, the illumination aircraft obtains the position of the launching aircraft, the position of the target, the laser switch-on and switch-off time and other information, calculates the illumination flight route, and finally generates the flight route of the dual aircraft cooperation.

[0067] Reference Figs. 1 to 3 The specific steps include:

[0068] Step 1, determining the input and output data of the method. The input data of the method are: (1) the launching aircraft: the latitude and longitude and height of the far boundary and near boundary positions of the launching basket, the latitude and longitude and height and speed information of the current position, and the attack scheme, wherein the connecting line of the far and near boundary points of the launching basket is directed to the target; (2) the latitude and longitude and height of the target position; (3) the illumination aircraft: the latitude and longitude and height and speed information of the current position; the output data of the method are the key route points of the flight route of the launching aircraft and the illumination aircraft.

[0069] Step 2, determining the related models and parameter definitions used in the method.

[0070] Firstly, the laser illumination time calculation model used in the method is provided by a third party.

[0071] Secondly, the basic coordinate system used in the method is the north-east coordinate system with the target as the origin, and in addition, the ground speed coordinate system is obtained by rotating the north-east coordinate system around the celestial coordinate axis by a certain angle, so that the north coordinate axis of the basic coordinate system is directed to the ground speed direction of the aircraft, and therefore the input and output data of the method need to be converted between coordinate systems; the occupation angle θ is defined as the included angle formed by the connecting line from the entering position p0 of the illumination aircraft to the target and then to the far boundary point of the launching basket, and the parameter can be set according to actual needs.

[0072] Then, the threshold value Δt of the time difference of the launching aircraft and the illumination aircraft respectively flying from the current position to the far boundary point of the launching basket and the entering position p0 of the illumination aircraft is determined. max .

[0073] Step 3, according to the illumination range data of the laser emitter on the illumination aircraft, a piecewise polynomial function fitting method is used to establish the illumination range constraint model of the laser emitter α max = f(β), wherein α maxThe relative irradiable pitch angle boundary value of the laser emitter pointing at the target in the irradiation machine body spherical coordinate system is β, and β is the azimuth angle of the target in the irradiation machine body spherical coordinate system, and the value range of β is 0-360 degrees. In addition, the maximum irradiation distance r_laser of the laser emitter is determined max .

[0074] Step 4, establish the entry position calculation model of the irradiation machine. Assuming that in the basic coordinate system, the matching direction of the irradiation machine relative to the delivery machine is inDir (the value of-1 indicates that the irradiation machine is matched on the right side of the delivery machine, and the value of 1 indicates that the irradiation machine is matched on the left side of the delivery machine), and the far boundary point of the delivery basket is p far , then the calculation formula of the north coordinate n0 and the east coordinate e0 of the entry position p0 of the irradiation machine is:

[0075]

[0076]

[0077] dis PT is the distance between the irradiation machine and the target (i.e. the machine-eye distance), is the azimuth angle of the p far point relative to the target in the basic coordinate system (north-east is positive), and θ is the occupation angle of the irradiation machine.

[0078] Step 5, establish the calculation model of the Dubins path of the irradiation machine and the straight-line flight irradiation path around the target. The Dubins path is the shortest feasible path between two directional points in a plane under the constraint of the minimum turning radius. Since the path calculation method is relatively mature, it will not be described here.

[0079] The specific flight route of the straight-line flight irradiation path around the target in this method is as follows: assuming that the aircraft flies at a constant speed during flight, the aircraft turns left or right at the maximum roll angle γ max during flight from the starting position p0, and the central angle of the turning circle is After turning, the straight-line flight phase begins; in the flight process, taking the moment when the starting position p0 as the reference point of relative time, if the laser start-up and shutdown times of the laser guided weapon are t s and t e , respectively, then the laser start-up point and shutdown point in the flight route can be determined according to the relationship between distance, time and speed, wherein the laser start-up point can be located in the turning phase or the straight-line flight phase, and the laser shutdown point is located in the straight-line flight phase. The specific calculation process is as follows:

[0080] Assuming that the starting position of the irradiation machine in the ground speed coordinate system is p0(x0, y0, z0), taking p0 as the relative time reference point, the ground speed is v, the height is h, and the maximum roll angle of the aircraft is γmax , then the minimum turning radius of the aircraft can be calculated according to the steady disc formula , where g is the gravity acceleration, dir is the turning direction (1 for right turn and -1 for left turn), and the turning center angle corresponding to the turning end point p1 is The following position information calculation process is performed:

[0081] The longitudinal coordinate x1, the lateral coordinate y1, and the speed direction of the turning end point p1 are calculated according to the following formulas: The relative time t1 is calculated according to the following formula:

[0082]

[0083]

[0084]

[0085]

[0086] If t s < t1, then the laser start point p s is located in the turning stage, and its longitudinal coordinate x s , lateral coordinate y s , and the turning center angle corresponding to the laser start point p s are calculated according to the following formulas:

[0087]

[0088]

[0089]

[0090] If t s > t1, then the laser start point p s and the laser end point p e are both located in the straight flight stage, and their longitudinal and lateral coordinates can be calculated according to the following formulas, where t = t s or t e :

[0091]

[0092]

[0093] Then, the position information of p1, p s , and p e ​The target's origin coordinates and the corresponding aircraft roll angle are used to obtain the target's coordinates (α, β, r) in the illuminating aircraft's spherical coordinate system at each position. The constraints for determining whether the aforementioned key waypoints located in the illuminating segment simultaneously meet the illuminating requirements are shown below:

[0094] α max =f(β)

[0095] α≤α max

[0096] r≤r_laser max

[0097] The above constraints are as follows: Calculate the actual azimuth angle β, actual elevation angle α, and target-eye distance r of the target in the spherical coordinate system of the illuminator based on the target's coordinates and the illuminator's coordinates at different positions. Then, calculate the maximum elevation angle α that can illuminate the target at that azimuth angle based on β. max Determine whether α and r satisfy the inequality constraint.

[0098] If the above constraints are satisfied, then p0, p1, and p in the ground velocity coordinate system will be... s p e The position information is converted to the base coordinate system and output for external use. If the above constraints are not met, the position of p0 or the turning center angle needs to be changed. Continue repeating the above location information calculation process until a solution is found.

[0099] Step 6: Determine the various dimensions of the search and their boundary values ​​for this method. In this method, the illuminator needs to perform a path search when calculating the illumination path; therefore, the search dimensions include the illuminator's coordination direction relative to the target (inDir∈{-1,1}), the distance between the illuminator and the target (i.e., the distance between the illuminator and the target), and the distance between the illuminator and the target (dis). PT ∈[dis min ,dis max ], turning direction dir∈{-1,1}, turning central angle Then determine dis respectively PT and The search step size.

[0100] Step 7: After determining the above model and related parameters, the delivery machine can calculate the Dubins path and time t from its current position to the far boundary point of the delivery basket. base Specifically: Assume the line connecting the far and near boundary points of the basket placement points points towards the target. Convert the current location of the machine and the latitude and longitude of the far boundary point of the basket placement point to the basic coordinate system. Based on the coordinates of the two points and their corresponding velocities and directions, calculate the waypoints in the Dubins path and the path length s. base Then, based on the ground speed v of the delivery machinethrow Calculate the time required to fly along the Dubins path (i.e., the baseline time).

[0101] Step 8: The delivery unit calculates the laser on / off time t based on information such as the attack plan, target location, and the near and far boundaries of the delivery basket. s t e Calculate the local machine from p far to p near Flight time t fly Then, the laser irradiation time calculation model was used to calculate the distance of the delivery machine from the far boundary point p of the delivery basket. far Nearest point p near Laser on / off time t for deploying laser-guided weapons s_far t e_far t s_near t e_near With p far The laser on / off time output by the laser transmitter is used as a reference point, and the formula for calculating the laser on / off time is as follows:

[0102] t s =min(t) s_far ,t s_near +t fly )

[0103] t e =max(t) e_far ,t e_near +t fly )

[0104] Step 9, the dispenser will deliver t s t e t base Information such as the location of the far boundary point of the dropped basket is transmitted to the illumination machine, and the Dubins waypoint information of the dropping machine flying from the current waypoint to the far boundary point of the dropped basket is output.

[0105] Step 10: The illuminator sequentially traverses the search flight path. The positions of the far boundary point of the drop basket and the target are transformed to the base coordinate system. Then, according to the illuminator's direction (inDir) and the distance between the illuminator and the target (dis), the coordinates are calculated. PT Turning direction (dir), turning center angle The search process iterates through each search dimension sequentially. The specific search process is shown below:

[0106] (4) The first search dimension is inDir. First, determine the value of inDir for the irradiation machine coordination direction, and then follow the search from dis... max to dis min Directional traversal search dis PTThe value of p0 is determined according to the entering position calculation model of step 4.

[0107] (5) According to the Dubins path length and speed of the illuminator, the Dubins path of the illuminator flying from the current position to the position p0 and the flight time are calculated determine whether the absolute error of t base is less than or equal to Δt max . If yes, the next step is executed, otherwise the values of dis PT and inDir are traversed and the step (1) is returned to recalculate p0.

[0108] (6) The values of dir and are traversed in turn, and the illuminating path around the target straight line is calculated according to the calculation model in step 5. If the illuminating section in the flight path meets the illumination condition constraint, the above search process is ended and the next step is executed, otherwise no solution is output.

[0109] Step 11, the illuminator outputs the flight path of cooperative illumination. At this time, the illuminator has found the illuminating flight path meeting the illumination condition constraint in the search process, and therefore the key waypoint of the illuminator flying from the current position to the end point of illumination is output according to the Dubins path of the illuminator flying from the current position to the position p0 and the illuminating path around the target straight line.

[0110] It can be seen that the key technologies of the method include the following aspects: first, the method provides a simple and practical calculation model of the flight path of the aircraft laser illumination; second, the method provides a laser guided illumination cooperation strategy of double aircrafts, which has good practicability; third, the method fully considers the synchronization and punctuality of the cooperation between multiple aircrafts and weapons in the double aircraft cooperation process, so as to ensure that the illuminator can provide laser guidance conditions for the weapon after the weapon is launched by the launching aircraft.

[0111] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications should be considered as the protection scope of the present application.

Claims

1. A laser-guided illumination method for aircraft based on a dual-aircraft cooperative system, characterized in that, Includes the following steps: Step 1, determine the input and output data The input data is: (1) Drop machine: latitude and longitude of the far and near boundary of the drop basket, latitude and longitude and speed information of the current location, and attack plan, wherein the line connecting the far and near boundary points of the drop basket points points to the target; (2) latitude and longitude of the target location; (3) Illumination machine: latitude and longitude and speed information of the current location; The output data is: key waypoints of the flight paths of the drop machine and the illumination machine; Step 2: Determine the relevant models and parameter definitions to be used. First, the relevant models used include a laser irradiation time calculation model; second, the basic coordinate system used is a north-sky-east coordinate system with the target as the origin. Furthermore, the ground velocity coordinate system used is a modified version of the basic coordinate system, rotated around the celestial axis by a certain angle so that the north axis of the basic coordinate system points towards the ground velocity direction of the aircraft. Therefore, both input and output data require coordinate system transformation; (Placement angle) Defined as the entry position of the irradiation machine The angle formed by the lines connecting the target point to the far point of the basket; Then, determine the distances from the current position of the delivery machine and the illumination machine to the farthest point of the delivery basket and the entry point of the illumination machine, respectively. Time difference threshold ; Step 3: Based on the irradiation range data of the laser emitter on the irradiation machine, a piecewise polynomial function fitting method is used to establish a constraint model for the irradiation range of the laser emitter. ,in This represents the boundary value of the illuminating elevation angle relative to the spherical coordinate system of the illuminating machine when the laser emitter is pointing at the target. The azimuth angle of the target in the spherical coordinate system of the irradiator is given; in addition, the maximum irradiation distance of the laser emitter is determined. ; Step 4: Establish an entry position calculation model for the irradiation machine based on Steps 1 and 2; Step 5: Based on Steps 1 to 3, establish calculation models for the Dubins path and the straight-line flight path around the target of the irradiation machine; Step 6: Determine the various dimensions of the search and their boundary values. When calculating the illumination path, the illumination machine needs to perform a path search; therefore, the search dimensions include the coordination direction of the illumination machine relative to the delivery machine. The distance between the irradiator and the target is the distance between the irradiator and the target. Turning direction Central angle of the turning circle Then determine respectively and The search step size; Step 7: After determining the above model and related parameters, the delivery machine can calculate the Dubins path from its current position to the far boundary of the delivery basket, as well as the time required to fly along the Dubins path. ; Step 8: The delivery unit calculates the laser on / off time based on information such as the attack plan, target location, and the near and far boundaries of the delivery basket. , ;Calculate the local machine from arrive Flight time Then, the laser irradiation time calculation model was used to calculate the distance of the delivery machine from the farthest point of the delivery basket. , near point Laser on / off time for deploying laser-guided weapons , , , ; Step 9, the dispenser will , , Information such as the location of the far boundary point of the dropped basket is transmitted to the illumination machine, and the Dubins waypoint information of the dropping machine from the current waypoint to the far boundary point of the dropped basket is output; Step 10: The illuminator sequentially traverses the search flight path; the positions of the far boundary point of the basket and the target are transformed into the basic coordinate system, and then the illuminator is aligned with the direction of the search. Eye-to-eye distance Turning direction Central angle of turning The search process iterates through each search dimension sequentially, as shown below: (1) The first layer of search dimension is First, determine the direction of the irradiation machine. The value of is then determined according to . arrive Directional traversal search The value of is then used to determine the entry position of the irradiation machine according to the entry position calculation model in step 4. ; (2) Based on the Dubins path length and speed of the irradiator, calculate the distance the irradiator will travel from its current position to... Dubins' path to location and its flight time ,judge and Is the absolute error less than or equal to ; If yes, proceed to the next step; otherwise, continue iterating. and Return to step (1) and recalculate the value. ; (3) Traverse sequentially and The value of is determined according to the calculation model in step 5. The straight flight path around the target is calculated. If the illumination segment in the flight path meets the illumination condition constraints, the above search process ends and the next step is executed. Otherwise, no solution is output. Step 11: The illuminator outputs the flight path for coordinated illumination; at this time, the illuminator has found an illumination path that meets the illumination condition constraints during the search process, therefore, based on the illuminator's flight path from its current position to... The Dubins path and the straight-line flight path around the target are given, and the critical waypoints for the illuminator to fly from the current position to the end point of the illumination are output.

2. The method as described in claim 1, characterized in that, In step 4, it is assumed that the direction of the irradiation machine relative to the delivery machine in the basic coordinate system is as follows: , A value of -1 indicates that the irradiation machine is positioned to the right of the delivery machine. A value of 1 indicates that the irradiator is positioned to the left of the delivery machine, and the farthest point of the delivery basket is [value missing]. Then the entry position of the irradiation machine North coordinates and eastward coordinates The calculation formula is: in, The distance between the irradiator and the target is the irradiation distance. Under the basic coordinate system The azimuth of the point relative to the target.

3. The method as described in claim 2, characterized in that, In step 5, the specific flight path of the illumination path around the target in a straight line is as follows: Assuming uniform flight speed during the flight, the aircraft starts from the entry position... To the left or right at the maximum roll angle Perform a turning flight, the central angle of the turn is After the turn, the flight enters a straight, level flight phase; during the flight, the flight proceeds to the next position. The current time is a relative time reference point. If the laser activation and deactivation times of a laser-guided weapon are known to be... , The laser activation and deactivation points along the flight path can then be determined based on the relationship between distance, time, and speed. The laser activation point can be located during the turning phase or the straight-line level flight phase, while the laser deactivation point is located during the straight-line level flight phase. The specific calculation process is as follows: Assume the entry position of the irradiator in the ground velocity coordinate system is ,by Using a relative time reference point, the ground speed is... The height is The maximum roll angle of the aircraft is Then, according to the stabilization formula Calculate the minimum turning radius of the aircraft, where It is the acceleration due to gravity. If the direction of the turn is... , A value of 1 indicates a right turn. A value of -1 indicates a left turn, and the aircraft flies to the end of the turn. The corresponding central turning angle is Then the following location information calculation process will be performed: End of turn ordinate x-axis , velocity direction Relative time The calculation formula is as follows: like Then the laser activation point During the turning phase, its ordinate x-axis The aircraft flew to the laser activation point The corresponding turning center angle The calculation formula is as follows: like Then the laser activation point With laser shutdown point Both are in the straight flight phase, and their horizontal and vertical coordinates can be calculated using the following formulas, where... : Then based on , , The coordinates of the target origin and the corresponding roll angle of the aircraft at each position are used to obtain the target's coordinates in the spherical coordinate system of the illuminating machine at each position. The constraints for determining whether critical waypoints located in the illuminated flight segment simultaneously meet the illumination requirements are as follows: In the constraint relationship: calculate the actual azimuth angle of the target in the spherical coordinate system of the illuminator based on the target's coordinates and the coordinates of the illuminator at different positions. Actual pitch angle Eye-to-eye distance Then according to Calculate the maximum elevation angle that can illuminate the target at this azimuth angle. ,judge and Can the inequality constraints be satisfied? If the constraints are met, then the coordinates in the ground velocity system will be... , , , The location information is transferred to the base coordinate system and output for external use; if the above constraints are not met, changes are required. Position or turning center angle Continue repeating the above location information calculation process until a solution is found.

4. The method as described in claim 1, characterized in that, The Dubins path is the shortest feasible path between two oriented points in a plane under the constraint of minimum turning radius.

5. The method as described in claim 1, characterized in that, In step 7, assuming the line connecting the far and near points of the basket placement points points towards the target, the latitude and longitude of the current machine position and the far point of the basket placement point are converted to the basic coordinate system. Based on the coordinates of the two points and their corresponding velocities and directions, the waypoints in the Dubins path and the path length are calculated. Then, based on the ground speed of the dispenser... Calculate the time required to fly along the Dubins path. .

6. The method as described in claim 1, characterized in that, In step 8, with The laser on / off time output by the laser transmitter is used as a reference point, and the formula for calculating the laser on / off time is as follows: 。 7. The method as described in claim 1, characterized in that, Placement angle Configure according to actual needs.

8. The method as described in claim 1, characterized in that, The value range is between 0 and 360 degrees.

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