Adaptive braking based aircraft heading maintenance method and apparatus

Abstract

The application provides an airplane heading keeping method and device based on adaptive braking, and belongs to the technical field of airplane braking control. The airplane heading keeping method based on adaptive braking carries out anti-yaw control on the brake optimization process and the state tracking process respectively. In the brake optimization process, the left and right sides are independently optimized, the selection and confirmation of the critical skid state of the left and right brakes of the airplane are realized through time sequence and skid amount calculation, airplane yaw is prevented, and airplane heading keeping is ensured. In the state tracking process, the left and right sides are independently used to calculate the real-time deceleration rate of the airplane wheel, the consistency of the real-time deceleration rate of the left and right sides is judged, when the difference exceeds the set threshold, the side with the high real-time deceleration rate of the airplane wheel actively reduces the brake pressure, and follows the side with the low real-time deceleration rate of the airplane wheel, the synchronous control of the real-time deceleration rate of the left and right sides of the airplane wheel is realized, airplane yaw is prevented, and airplane heading keeping is ensured.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aircraft brake control, and particularly relates to an aircraft heading keeping method and device based on adaptive braking. BACKGROUND

[0002] During the aircraft landing braking process, heading keeping is very important, and the heading directly affects the safety of aircraft landing. The conventional braking process corrects the heading deviation through differential braking. Adaptive braking is a kind of aircraft braking control method with full braking command and full pressure regulation. The effect of correcting the heading deviation through differential braking is not good, and even may cause braking overshoot oscillation. The adaptive braking process includes a braking optimization process and a state tracking process. The braking optimization process refers to a process of finding a critical slip state with the increase of braking pressure after the maximum braking command is applied. In the critical slip state, the braking torque is equal to the ground combined torque, and the aircraft wheel will not slip, which is the state with the highest braking efficiency. The braking control system determines the critical deceleration rate target according to the critical slip state. The state tracking process is a full pressure regulation process for keeping braking in the critical slip state after the braking optimization process ends. According to the aircraft braking design principle, the aircraft braking control is independent left and right control. The adaptive braking is based on the emergency braking intention of the pilot, and is often used when the aircraft speed is in the medium speed or high speed and the brake pedal is fully pressed. In the case of emergency braking, the yaw is unacceptable. In the braking critical optimization process, since the left and right independent optimization, the critical deceleration rate targets determined according to the left and right critical slip states may be out of sync or inconsistent in value, thereby possibly causing the aircraft to continuously yaw. In the state tracking process, although the left and right critical deceleration rate targets are consistent, the real-time deceleration rates of the aircraft wheels are inconsistent, for example, in the case of unilateral wheel locking, the aircraft yaw phenomenon may also occur.

[0003] Based on the adaptive aircraft full braking design principle, the conventional differential braking correction may make the braking system control exit the critical slip state control, and easily induce the left and right repeated swing deviation of the system heading, and the heading is not easy to keep. The conventional differential braking correction control method has the following shortcomings: 1. It has limitations and is not suitable for adaptive braking control; 2. It easily induces the left and right repeated swing deviation of the system heading, and the heading is not easy to keep, and the safety is low; 3. It excessively depends on the pilot operation, and is not easy to control. The conventional differential braking correction control method controls the yaw through the pilot control footrest stroke. In the case of conventional proportional braking control, the aircraft use requirements can be basically met, but there is also the problem of excessive correction and the heading is not easy to keep. Based on the adaptive braking optimization process and the state tracking process, based on the adaptive aircraft full braking design principle, the active anti-yaw control of the whole braking process is needed, the logic is rigorous, the synchronous response requirement is high, and the difficulty is great. SUMMARY

[0004] To avoid yaw during the adaptive braking optimization and state tracking processes and improve the safety of adaptive braking, this invention proposes an aircraft heading maintenance method and device based on adaptive braking. The technical solution is as follows:

[0005] Firstly, an aircraft heading maintenance method based on adaptive braking is provided, including:

[0006] Step 1: Determine whether adaptive braking is required based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command. If adaptive braking is required, proceed to Step 2.

[0007] Step 2: When adaptive braking is required, maintain course control based on the critical slippage state during the braking optimization process; then proceed to Step 3.

[0008] Step 3: During the state tracking process, maintain course control based on the real-time deceleration rates of the left and right wheels.

[0009] Step one includes:

[0010] Determine the aircraft speed V P Is it greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed;

[0011] Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b is the percentage of the full travel of the pilot's braking command, U M Full-stroke voltage for the pilot's braking command;

[0012] If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b%U M And the right pilot's brake command U R ≥b%U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

[0013] Step two includes:

[0014] When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count;

[0015] When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η 0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slip state η0 = the right critical slip state η 0y .

[0016] Step three includes:

[0017] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time reduction rate a of the right engine wheel vy ;

[0018] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy The difference |Δa v |;

[0019] When the difference |Δa v When |>k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference |Δa is reached. v |≤k;k is the minimum threshold at which the difference in the deceleration rates of the left and right wheels of the aircraft does not affect the heading.

[0020] Specifically, the real-time reduction rate 'a' of the left engine wheel can be calculated based on the speed difference between the engine wheels. vz and the real-time deceleration rate a of the right engine wheel vy .

[0021] In step three, k is 5 m / s 2 ~7m / s 2 .

[0022] Secondly, an aircraft heading-keeping device based on adaptive braking is provided, comprising:

[0023] The judgment module is used to determine whether adaptive braking is needed based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command.

[0024] The control module is used to perform heading control based on the critical slip state during the braking optimization process when adaptive braking is required; and to perform heading control during the state tracking process based on the real-time deceleration rates of the left and right wheels.

[0025] The judgment module is specifically used for:

[0026] Determine the aircraft speed V P Is it greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed;

[0027] Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b is the percentage of the full travel of the pilot's braking command, U M Full-stroke voltage for the pilot's braking command;

[0028] If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b%U M And the right pilot's brake command U R ≥b%U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

[0029] The control module is specifically used for:

[0030] When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count;

[0031] When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η 0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slip state η0 = the right critical slip state η 0y .

[0032] Furthermore, the control module is specifically used for:

[0033] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy ;

[0034] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy The difference |Δa v |;

[0035] When the difference |Δa v When |>k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference |Δa is reached. v|≤k;k is the minimum threshold at which the difference in the deceleration rates of the left and right wheels of the aircraft does not affect the heading.

[0036] Compared to the differential braking correction control method in the prior art, the present invention is applicable to adaptive braking; it can actively maintain the heading and avoid repeated left and right swaying and deviation from the heading, so it is highly safe; it can automatically maintain the heading during the braking optimization process and the state tracking process, so it can achieve automatic control.

[0037] The adaptive braking-based aircraft heading maintenance method uses aircraft speed V P Left pilot brake command U L Right pilot brake command U R The system determines whether adaptive braking should be initiated. If adaptive braking is initiated, aircraft heading control is performed. During braking optimization, the critical deceleration rate targets for left and right braking are determined based on the critical slip state η0, and synchronized braking control is implemented on both sides to avoid yaw problems caused by inconsistent timing or inconsistent critical deceleration rate targets. During state tracking, the system uses the real-time deceleration rate a of the left wheel... vz and the real-time deceleration rate a of the right engine wheel vy Difference | Δa v |Calculate and compare with the threshold k, when the difference |Δa v If |>k, then the side with the higher real-time deceleration rate of the wheel actively reduces the braking pressure until the difference |Δa| is reached. v |≤k;When the difference|Δa v If |≤k, the current control is maintained, thereby preventing aircraft yaw and ensuring heading maintenance. Through brake optimization and state tracking process control, adaptive braking-based heading maintenance control is achieved, improving the safety and maneuverability of the braking system. Attached Figure Description

[0038] Figure 1 This is a flowchart of an aircraft heading maintenance method based on adaptive braking provided in an embodiment of the present invention. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0040] This invention provides a control method based on an anti-skid braking system. The anti-skid braking system is applicable to fly-by-wire anti-skid braking systems. For example... Figure 1 As shown, the aircraft heading maintenance method based on adaptive braking provided by the present invention includes the following steps:

[0041] Step 1: Determine whether adaptive braking is required based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command. If adaptive braking is required, proceed to Step 2.

[0042] In one possible implementation, step one includes the following sub-steps:

[0043] 1. Determine the aircraft's speed V P Whether it is greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed, which is generally taken as 20km / h~30km / h;

[0044] 2. Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b is the percentage of the full travel of the pilot's braking command, typically taken as 80%–90%. M The voltage at full stroke for the pilot's braking command is typically 4V to 5V.

[0045] 3. If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b%U M And the right pilot's brake command U R ≥b%U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

[0046] This step determines whether adaptive braking is needed. If adaptive braking is initiated, heading hold control is performed.

[0047] Step 2: When adaptive braking is required, maintain heading control during the braking optimization process; proceed to Step 3.

[0048] In one possible implementation, step two includes the following sub-steps:

[0049] 1. When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count;

[0050] Determining whether a left-critical slippage state η has occurred 0z In this invention, based on the derivative of the braking slip ratio, when the derivative of the left braking slip ratio is 0, a left critical slip state η is determined to have occurred. 0z .

[0051] 2. When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slip state η0 = the right critical slip state η 0y .

[0052] Determining whether a right-critical slippage state η has occurred 0y In this invention, based on the derivative of the braking slip ratio, when the derivative of the right braking slip ratio is 0, a right critical slip state η is determined to have occurred. 0y .

[0053] Once the critical slippage state η0 is determined, the heading control is completed.

[0054] In related technologies, when the derivative of the braking slip ratio is 0, the braking torque equals the ground contact torque, resulting in the highest braking efficiency.

[0055] This step follows the first-come-first-served principle, selecting and confirming the critical slip state η0. Based on the critical slip state η0, the left and right braking critical deceleration rate targets are determined, and left and right synchronous braking control is performed, thereby avoiding yaw problems caused by inconsistent timing or inconsistent braking critical deceleration rate targets.

[0056] Step 3: During the state tracking process, maintain course control based on the real-time deceleration rates of the left and right wheels.

[0057] In one feasible implementation, step three includes the following sub-steps:

[0058] 1. Calculate the real-time reduction rate a of the left engine wheel. vz and the real-time deceleration rate a of the right engine wheel vy ;

[0059] The real-time deceleration rate a of the left engine wheel is calculated using formulas (1) and (2). vz and the real-time deceleration rate a of the right engine wheel vy :

[0060] Wheel speed difference ΔV W =V W1 -V W0 (1)

[0061] Real-time wheel reduction rate a v =-ΔV W / t (2)

[0062] In formula (1), V W1 V is the final velocity. W0 The initial velocity;

[0063] In formula (2), t is the control duration.

[0064] 2. Calculate the real-time reduction rate a of the left engine wheel. vz and the real-time deceleration rate a of the right engine wheel vy The difference |Δa v |;

[0065] The real-time deceleration rate a of the left engine wheel is calculated using formula (3). vz and the real-time deceleration rate a of the right engine wheel vy The difference |Δa v |:

[0066] |Δa v |=a vz -a vy (3)

[0067] 3. When the difference |Δa v When |>k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference |Δa is reached. v |≤k. Where k is the minimum threshold at which the difference in deceleration rates between the left and right aircraft wheels does not affect the heading. If the real-time deceleration rate of the wheels exceeds the threshold k, it indicates that the wheels are locked and have lost their braking capability. The threshold k is typically taken as 5 m / s². 2 ~7m / s 2 .

[0068] This step involves tracking the real-time deceleration rate 'a' of the left engine wheel during the adaptive braking state tracking process. vz and the real-time deceleration rate a of the right engine wheel vy Difference | Δa v |Calculate and compare with the threshold k, when the difference |Δa v When | > k, the side with the higher real-time deceleration rate of the rotor actively reduces the braking pressure until the difference |Δa| is reached. v |≤k;When the difference|Δa v When |≤k, the current control is maintained to prevent the aircraft from yawing and ensure that the aircraft's heading is maintained.

[0069] This invention provides an aircraft heading control method based on adaptive braking, which performs anti-yawing control during both the braking optimization process and the state tracking process. During the braking optimization process, the left and right wheels are optimized independently. Through timing and slippage calculations, the critical slippage states of the left and right wheels are selected and confirmed to prevent yawing and ensure heading maintenance. During the state tracking process, the left and right wheels independently calculate the real-time deceleration rate and determine the consistency of the real-time deceleration rates. However, if the difference exceeds a set threshold, the side with the higher real-time deceleration rate actively reduces braking pressure to follow the side with the lower real-time deceleration rate, achieving synchronous control of the real-time deceleration rates of the left and right wheels, thereby preventing yawing and ensuring heading maintenance.

[0070] An embodiment of the present invention proposes an aircraft heading maintenance method based on adaptive braking, comprising the following steps:

[0071] Step 1: Determine if adaptive braking is required. If adaptive braking is required, proceed to Step 2.

[0072] The anti-skid failure speed 'a' is set to 25 km / h; the pilot's braking command full travel U M The value is 5V; the percentage b of the full travel of the pilot's braking command is 85%.

[0073] When the aircraft speed V P =200km / h, and the left pilot brake command U L =5V, and the right pilot's brake command U R =5V, which is suitable for adaptive braking and heading control.

[0074] Step 2: When adaptive braking is required, perform heading hold control during the braking optimization process. Proceed to Step 3.

[0075] I z1 =I z2 =I z3 =I z4 =I z5 =I z6 =0, at i=6, the derivative of the left wheel brake slip ratio is 0, reaching the left critical slip state η. 0z i stops counting; at the same time, I y1 =I y2 =1,I y3 =I y4 =I y5 =I y6 =0, when i=6, the right critical slip state η has not been reached. 0y ,i stops counting. Critical slippage state η0 = left critical slippage state η 0z .

[0076] Once the critical slippage state η0 is determined, the heading control is completed.

[0077] Step 3: Perform heading hold control during state tracking.

[0078] k takes a value of 6 m / s 2 t takes a value of 1 second. Left side V W1 Take the value as 200km / h, V W0 Value taken as 190km / h; V on the right W1 Take the value as 200km / h, V W0 Taking a value of 50 km / h, a was calculated. vz =2.78m / s 2a vy = 41.67m / s 2 ,|Δa v |=38.89m / s 2 6 m / s greater than the threshold k 2 The right landing gear actively reduces braking pressure to prevent the aircraft from yawing to the right.

[0079] Another embodiment of the present invention proposes an aircraft heading maintenance method based on adaptive braking, comprising the following steps:

[0080] Step 1: Determine if adaptive braking is required. If adaptive braking is required, proceed to Step 2.

[0081] The anti-skid failure speed 'a' is set to 25 km / h; the pilot's braking command full travel U M The value is 5V; the percentage b of the full travel of the pilot's braking command is 85%.

[0082] When the aircraft speed V P =220km / h, and the left pilot's braking command U L =5V, and the right pilot's brake command U R =5V, which is suitable for adaptive braking and heading control.

[0083] Step 2: When adaptive braking is required, perform heading hold control during the braking optimization process. Proceed to Step 3.

[0084] I y1 =I y2 =I y3 =I y4 =I y5 =I y6 =0, at i=6, the derivative of the right wheel brake slip ratio is 0, reaching the right critical slip state η. 0y i stops counting; at the same time, I z1 =I z2 =I z3 =I z4 =I z5 =I z6 =0, at i=6, the left critical slip state η has not been reached. 0y ,i stops counting. Critical slip state η0 = right critical slip state η 0y .

[0085] Once the critical slippage state η0 is determined, the heading control is completed.

[0086] Step 3: Perform heading hold control during state tracking.

[0087] k is set to 6.5 m / s2 t takes a value of 1.2s. Left side V W1 Take the value as 200km / h, V W0 Value taken as 120km / h; V on the right W1 Take the value as 200km / h, V W0 The value is taken as 185 km / h, and a is calculated. vz =18.55m / s 2 a vy =3.48m / s 2 ,|Δa v |=15.07m / s 2 6.5 m / s greater than the threshold k 2 The left landing gear actively reduces braking pressure to prevent the aircraft from yawing to the left.

[0088] The present invention also provides an aircraft heading-keeping device based on adaptive braking, comprising:

[0089] The judgment module is used to determine whether adaptive braking is needed based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command.

[0090] The control module is used to perform heading control based on the critical slip state during the braking optimization process when adaptive braking is required; and to perform heading control during the state tracking process based on the real-time deceleration rates of the left and right wheels.

[0091] The judgment module is specifically used for:

[0092] Determine the aircraft speed V P Is it greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed;

[0093] Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b is the percentage of the full travel of the pilot's braking command, U M Full-stroke voltage for the pilot's braking command;

[0094] If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b%U M And the right pilot's brake command U R ≥b%U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

[0095] The control module is specifically used for:

[0096] When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count;

[0097] When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η 0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slip state η0 = the right critical slip state η 0y .

[0098] Furthermore, the control module is specifically used for:

[0099] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy ;

[0100] Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy The difference |Δa v |;

[0101] When the difference |Δa v When |>k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference |Δa is reached. v |≤k;k is the minimum threshold at which the difference in the deceleration rates of the left and right wheels of the aircraft does not affect the heading.

[0102] The above description merely illustrates embodiments of the present invention and is quite specific and detailed; however, it should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Furthermore, any parts of the present invention not described in detail are conventional techniques.

Claims

1. A method for maintaining an aircraft's heading based on adaptive braking, characterized in that, include: Step 1: Determine whether adaptive braking is required based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command. If adaptive braking is required, proceed to Step 2. Step 2: When adaptive braking is required, heading control is performed based on the critical slip state during the braking optimization process; the critical slip state η0 is selected and confirmed, and the left and right braking critical deceleration rate targets are determined based on the critical slip state η0 to perform left and right synchronous braking control; then proceed to Step 3. Step 3: Perform heading control during state tracking based on the real-time deceleration rates of the left and right wheels. Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy ; Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy The difference | Δa v |; When the difference | Δa v When | > k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference | Δa is reached. v |≤k; k is the minimum threshold at which the difference in the deceleration rates of the left and right wheels of the aircraft does not affect the heading.

2. The method according to claim 1, characterized in that, Step one includes: Determine the aircraft speed V P Is it greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed; Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b represents the percentage of the full travel of the pilot's braking command, U M Full-stroke voltage for the pilot's braking command; If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b % U M And the right pilot's brake command U R ≥b % U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

3. The method according to claim 1, characterized in that, Step two includes: When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count; When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η 0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slippage state η0 = the right critical slippage state η 0y .

4. The method according to claim 1, characterized in that, Calculate the real-time deceleration rate 'a' of the left engine wheel based on the speed difference between the engine wheels. vz and the real-time deceleration rate a of the right engine wheel vy .

5. The method according to claim 1, characterized in that, In step three, k is 5 m / s 2 ~7 m / s 2 .

6. An aircraft heading-keeping device based on adaptive braking, characterized in that, include: The judgment module is used to determine whether adaptive braking is needed based on the aircraft speed, the left pilot's braking command, and the right pilot's braking command. The control module is used to perform heading control based on the critical slip state during the braking optimization process when adaptive braking is required. It selects and confirms the critical slip state η0, determines the critical deceleration rate targets for left and right braking based on the critical slip state η0, and performs synchronous braking control for left and right wheels. It also performs heading control during state tracking based on the real-time deceleration rates of the left and right wheels. The control module is also specifically used for: Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy ; Calculate the real-time reduction rate a of the left engine wheel vz and the real-time deceleration rate a of the right engine wheel vy The difference | Δa v |; When the difference | Δa v When | > k, determine the side with the higher real-time deceleration rate of the impeller and actively reduce the braking pressure until the difference | Δa is reached. v |≤k; k is the minimum threshold at which the difference in the deceleration rates of the left and right wheels of the aircraft does not affect the heading.

7. The apparatus according to claim 6, characterized in that, The judgment module is specifically used for: Determine the aircraft speed V P Is it greater than or equal to the preset anti-skid failure speed a km / h; where a is the anti-skid failure speed; Determine the left pilot's brake command U L Right pilot brake command U R Are they all greater than or equal to the full travel U of the pilot's braking command? M b%; b represents the percentage of the full travel of the pilot's braking command, U M Full-stroke voltage for the pilot's braking command; If the aircraft speed V P ≥a, and the left pilot's brake command U L ≥b % U M And the right pilot's brake command U R ≥b % U M If adaptive braking is required, then adaptive braking is not required; otherwise, it is not required.

8. The apparatus according to claim 7, characterized in that, The control module is specifically used for: When the left anti-slip current I zi ≤0 and produces a left-hand critical slip state η 0z At this point, the right critical slip state η 0y No right-hand critical slip state η was generated. 0y If identification is no longer performed, then the critical slippage state η0 = the left critical slippage state η 0z Where i = 1, 2, 3, ..., i is the control cycle count; When the right anti-slip current I yi ≤0 and produces a right-hand critical slip state η 0y At this point, the left critical slip state η 0z No left-hand critical slip state η was generated. 0z If identification is no longer performed, then the critical slippage state η0 = the right critical slippage state η 0y .

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