A method for adaptively selecting reference points on aircraft paths

Abstract

The present invention relates to an adaptive selection method for aircraft route reference points, belonging to the field of aircraft technology. Through an adaptive selection mechanism for route reference points, the distance of route reference points is adaptively adjusted according to the aircraft speed and track tracking error, so that the navigation control system has a good route tracking effect within a large flight speed and track tracking error range. The present invention introduces an adaptive selection mechanism for route reference points into the nonlinear navigation control law of the aircraft, avoiding the problem that the change in aircraft speed may cause the navigation instruction to be too large or too small, and can ensure that the aircraft can accurately track the reference route within a large flight speed range.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft route tracking control, and in particular relates to an aircraft route reference point adaptive selection method. Background Art

[0002] The lateral navigation system generally calculates the roll angle command signal based on the position of the aircraft and the desired route, and realizes route tracking through coordinated turns. In the existing nonlinear navigation control law, the selection of route reference points directly affects the quality of route tracking. If the selection error of the route reference point is too large, it is impossible to ensure that the aircraft can accurately track the reference route within a large flight speed range.

[0003] Therefore, at this stage, it is necessary to design an adaptive selection method for aircraft path reference points to solve the above problems. Summary of the invention

[0004] The present invention aims to provide an adaptive selection method for aircraft route reference points, which is used to solve the technical problems existing in the above-mentioned prior art. The lateral navigation system generally calculates the roll angle command signal according to the position of the aircraft and the expected route, and realizes route tracking through coordinated turning. In the existing nonlinear navigation control law, the selection of route reference points directly affects the quality of route tracking. If the selection error of the route reference points is too large, it is impossible to ensure that the aircraft can accurately track the reference route within a large flight speed range.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A method for adaptively selecting reference points on an aircraft route comprises the following steps:

[0007] S1: Introducing the adaptive selection mechanism of path reference points into the nonlinear navigation control law of the aircraft;

[0008] S2: Based on step S1, the distance of the route reference point is adaptively adjusted according to the aircraft speed and the track tracking error;

[0009] S3: Based on step S2, the navigation control system performs route tracking within the track tracking error range according to the adaptively adjusted route reference point distance.

[0010] Furthermore, in step S1, the nonlinear navigation control law of the aircraft is derived as follows:

[0011]

[0012] Among them, a y is the lateral acceleration of the aircraft; V is the speed of the aircraft; L is the lift of the aircraft; m is the mass of the aircraft; φ dis the roll angle command signal; g is the gravity acceleration; D1 is the distance of the route reference point; η P is the track reference angle; R is the turning radius of the aircraft at the current moment.

[0013] Furthermore, in step S1, the route reference point adaptive selection mechanism is as follows:

[0014] When the aircraft speed V and the distance D1 from the route reference point are constant, the roll angle command signal φ in equation (1) is d Only with the track reference angle η p The size of the track tracking error d is used to approximate the calculation of sinη p We can get:

[0015]

[0016] In formula (2), when the aircraft speed V is constant, the distance D1 of the route reference point can be adaptively adjusted according to the aircraft speed V and the track tracking error d, and the calculation formula is:

[0017]

[0018] Among them, k D1 >0, k D2 >0 and k D3 >0 is a design parameter; D0>0 is a length value pre-set according to the aircraft parameters; when the absolute value of the track tracking error d is larger, that is, the aircraft is farther away from the expected route, the calculated D1 is smaller, the controller generates a larger roll angle command signal, and the aircraft approaches the route with a larger yaw angular velocity; when the absolute value of the track tracking error d is smaller, D1 is correspondingly larger, and the controller generates a smaller roll angle command signal, so that the aircraft can track the route smoothly; the influence of the flight speed V is considered in formula (3). When the flight speed increases, D1 increases accordingly; when the flight speed decreases, D1 decreases accordingly.

[0019] Further, when the aircraft tracks a straight path;

[0020] O g x g y g is the ground coordinate system, x g The y axis points due north. g The axis points to the east; Point P1 and Point P2 are the starting point and the end point of the straight line route respectively; d1 is the distance from the center point O of the aircraft to Point P1; d C is the distance from the reference point P to point P1; P for With the ground coordinate axis x g The angle between the axes; ψ P for With the ground coordinate axis x g The angle between the axes; λ P for and The angle between them; let the coordinate of the aircraft in the ground coordinate system be (y gu ,x gu ), the coordinates of point P1 and point P2 in the ground coordinate system are (y g1 ,x g1 ) and (y g2 ,x g2 );

[0021] The lateral nonlinear navigation control law is:

[0022]

[0023] Use the track tracking error d to approximate sinη p We can get:

[0024]

[0025] In formula (12), the distance D1 of the route reference point can be adaptively adjusted according to the flight speed V and the track tracking error d, and the calculation formula is:

[0026]

[0027] In formula (13), d, The calculation process is as follows:

[0028]

[0029] Where d(k) is the value of d in the current beat; d(k-1) is the value of d in the previous beat; Δt is the calculation period;

[0030] λ P The calculation formula of d1 is:

[0031]

[0032] χ P The calculation formula is:

[0033]

[0034] Among them, Δ χ is the angle compensation, and the expression is:

[0035]

[0036]

[0037] Among them, Δ ψis the angle compensation, and the expression is:

[0038]

[0039] An aircraft path reference point adaptive selection device adopts the above-mentioned aircraft path reference point adaptive selection method to perform aircraft path reference point adaptive selection.

[0040] An aircraft path reference point adaptive selection system adopts the above-mentioned aircraft path reference point adaptive selection method to perform aircraft path reference point adaptive selection.

[0041] An electronic device, comprising:

[0042] processor;

[0043] a memory for storing processor-executable instructions;

[0044] The processor implements the above-mentioned method for adaptively selecting reference points on an aircraft path by running the executable instructions.

[0045] A computer storage medium stores a computer program, which, when executed, executes the above-mentioned method for adaptively selecting reference points on an aircraft path.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] One of the beneficial effects of the present scheme is that it provides a method for adaptively selecting path reference points of an aircraft. In the lateral nonlinear navigation control law, the distance of the path reference points is designed to be adaptively adjusted with the flight speed, so that the navigation control system has a good path tracking effect within a large flight speed and track tracking error range. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 The figure is a flowchart of the method steps of an embodiment of the present application.

[0049] Figure 2 This is a schematic diagram of lateral navigation according to an embodiment of the present application.

[0050] Figure 3 This is a schematic diagram of the straight-line route tracking of an aircraft according to an embodiment of the present application. DETAILED DESCRIPTION

[0051] Below in conjunction with the appended Figure 1 -Attached Figure 3, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] The lateral navigation system generally calculates the roll angle command signal based on the position of the aircraft and the desired route, and realizes route tracking through coordinated turns. In the existing nonlinear navigation control law, the selection of route reference points directly affects the quality of route tracking. If the selection error of the route reference point is too large, it is impossible to ensure that the aircraft can accurately track the reference route within a large flight speed range.

[0053] Example:

[0054] like Figure 1 As shown, a method for adaptively selecting reference points of an aircraft path is proposed, comprising the following steps:

[0055] S1: Introducing the adaptive selection mechanism of path reference points into the nonlinear navigation control law of the aircraft;

[0056] S2: Based on step S1, the distance of the route reference point is adaptively adjusted according to the aircraft speed and the track tracking error;

[0057] S3: Based on step S2, the navigation control system performs route tracking within the track tracking error range according to the adaptively adjusted route reference point distance.

[0058] Among them, the schematic diagram of lateral nonlinear navigation control is as follows: Figure 2 As shown. Point O is the center point of the aircraft; V is the flight velocity vector; Point P is the reference point selected on the desired route, D1 is the distance from the route reference point; η P is the track reference angle; the arc OP is tangent to V, R is the turning radius of the aircraft at the current moment, and R will change continuously during the route tracking process, C R is the corresponding point; d is the track tracking error.

[0059] 1) According to Figure 1 , the lateral nonlinear navigation control law can be obtained through the following derivation:

[0060]

[0061] Among them, a y is the lateral acceleration of the aircraft; V is the speed of the aircraft; L is the lift of the aircraft; m is the mass of the aircraft; φ d is the roll angle command signal; g is the gravitational acceleration.

[0062] 2) When the flight speed V and the distance D1 from the route reference point are constant, the roll angle command signal φ in equation (1) is d Only with the track reference angle η p The size of the track tracking error d is used to approximate the calculation of sinη p We can get:

[0063]

[0064] 3) In formula (2), when the flight speed V is constant, the size of D1 has a greater impact on the size of the controller gain. To this end, an adaptive selection mechanism for the route reference point is proposed. The route reference point distance D1 can be adaptively adjusted according to the flight speed V and the track tracking error d. The calculation formula is:

[0065]

[0066] Among them, k D1 >0, k D2 >0 and k D3 >0 is a design parameter; D0>0 is a length value pre-set according to the aircraft parameters. When the absolute value of the track tracking error d is large, that is, the aircraft is far away from the expected route, the calculated D1 is small, the controller generates a larger roll angle command signal, and the aircraft approaches the route at a larger yaw rate; when the absolute value of the track tracking error d is small, D1 becomes larger accordingly, and the controller generates a smaller roll angle command signal, so that the aircraft can track the route smoothly. The influence of the flight speed V is also considered in formula (3). When the flight speed is high, D1 increases accordingly; when the flight speed is low, D1 decreases accordingly, avoiding the situation where the ratio of V to D1 in formula (2) is too large or too small.

[0067] Take the example of an aircraft tracking a straight line route. Figure 2 shown.

[0068] Figure 3 In, O g x g y g is the ground coordinate system, x g The y axis points due north. g The axis points to the east; Point P1 and Point P2 are the starting point and the end point of the straight line route respectively; d1 is the distance from the center point O of the aircraft to Point P1; d C is the distance from the reference point P to point P1; P for With the ground coordinate axis x g The angle between the axes; ψ P for With the ground coordinate axis x g The angle between the axes; λP for and The angle between them. Suppose the coordinate of the aircraft in the ground coordinate system is (y gu ,x gu ), the coordinates of point P1 and point P2 in the ground coordinate system are (y g1 ,x g1 ) and (y g2 ,x g2 ).

[0069] 1) The lateral nonlinear navigation control law is:

[0070]

[0071] 2) Use the track tracking error d to approximate sinη p We can get:

[0072]

[0073] 3) In formula (12), the selection of the route reference point distance D1 directly affects the quality of the route tracking effect. To this end, an adaptive selection mechanism for route reference points is proposed. The route reference point distance D1 can be adaptively adjusted according to the flight speed V and the track tracking error d. The calculation formula is:

[0074]

[0075] 4) In formula (13), d, The calculation process is as follows:

[0076]

[0077] Wherein, d(k) is the value of d in the current beat; d(k-1) is the value of d in the previous beat; Δt is the calculation period.

[0078] λ P The calculation formula of d1 is:

[0079]

[0080] χ P The calculation formula is:

[0081]

[0082] Among them, Δ χ is the angle compensation, and the expression is:

[0083]

[0084]

[0085] Among them, Δ ψ is the angle compensation, and the expression is:

[0086]

[0087] The above are preferred embodiments of the present invention. Any changes made according to the technical solution of the present invention, as long as the resulting functions do not exceed the scope of the technical solution of the present invention, belong to the protection scope of the present invention.

Claims

1. A method for adaptively selecting reference points on an aircraft path, characterized in that: The following steps are involved: S1: Introducing the adaptive selection mechanism of path reference points into the nonlinear navigation control law of the aircraft; S2: Based on step S1, the distance of the route reference point is adaptively adjusted according to the aircraft speed and the track tracking error; S3: Based on step S2, the navigation control system performs route tracking within the track tracking error range according to the adaptively adjusted route reference point distance; The nonlinear navigation control law of the aircraft is derived as follows: Among them, a y is the lateral acceleration of the aircraft; V is the speed of the aircraft; L is the lift of the aircraft; m is the mass of the aircraft; φ d is the roll angle command signal; g is the gravity acceleration; D1 is the distance of the route reference point; η P is the track reference angle; R is the turning radius of the aircraft at the current moment; The route reference point adaptive selection mechanism is as follows: When the aircraft speed V and the distance D1 from the route reference point are constant, the roll angle command signal φ in equation (1) is d Only with the track reference angle η p The size of the track tracking error d is used to approximate the calculation of sinη p We can get: In formula (2), when the aircraft speed V is constant, the distance D1 of the route reference point can be adaptively adjusted according to the aircraft speed V and the track tracking error d, and the calculation formula is: Among them, k D1 >0, k D2 >0 and k D3 >0 is a design parameter; D0>0 is a length value pre-set according to the aircraft parameters; when the absolute value of the track tracking error d is larger, that is, the aircraft is farther away from the expected route, the calculated D1 is smaller, the controller generates a larger roll angle command signal, and the aircraft approaches the route with a larger yaw angular velocity; when the absolute value of the track tracking error d is smaller, D1 is correspondingly larger, and the controller generates a smaller roll angle command signal, so that the aircraft can track the route smoothly; the influence of the flight speed V is considered in formula (3). When the flight speed increases, D1 increases accordingly; when the flight speed decreases, D1 decreases accordingly.

2. The method for adaptively selecting reference points for an aircraft path according to claim 1, characterized in that: When the aircraft is tracking a straight path; O g x g y g is the ground coordinate system, x g The y axis points due north. g The axis points to the east; Point P1 and Point P2 are the starting point and end point of the straight route respectively; d1 is the distance from the center point O of the aircraft to point P1; d C is the distance from reference point P to point P1; P for With the ground coordinate axis x g The angle between the axes; ψ P for With the ground coordinate axis x g The angle between the axes; λ P for and The angle between them; let the coordinate of the aircraft in the ground coordinate system be (y gu ,x gu ), the coordinates of point P1 and point P2 in the ground coordinate system are (y g1 ,x g1 ) and (y g2 ,x g2 ); The lateral nonlinear navigation control law is: Use the track tracking error d to approximate sinη p We can get: In formula (12), the distance D1 of the route reference point can be adaptively adjusted according to the flight speed V and the track tracking error d, and the calculation formula is: In formula (13), d, The calculation process is as follows: Where d(k) is the value of d in the current beat; d(k-1) is the value of d in the previous beat; Δt is the calculation period; λ P The calculation formula of d1 is: χ P The calculation formula is: Among them, Δ χ is the angle compensation, and the expression is: Among them, Δ ψ is the angle compensation, and the expression is:

3. An aircraft route reference point adaptive selection device, characterized in that: Adopting the method for adaptively selecting aircraft path reference points as described in any one of claims 1 to 2, adaptively selecting aircraft path reference points is performed.

4. An aircraft path reference point adaptive selection system, characterized in that: Adopting the method for adaptively selecting aircraft path reference points as described in any one of claims 1 to 2, adaptively selecting aircraft path reference points is performed.

5. An electronic device, characterized in that: include: processor; a memory for storing processor-executable instructions; The processor implements the method for adaptively selecting aircraft path reference points as described in any one of claims 1 to 2 by running the executable instructions.

6. A computer storage medium, characterized in that: The storage medium stores a computer program, which, when executed, executes the method for adaptively selecting aircraft path reference points as described in any one of claims 1 to 2.

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