A method for controlling an electronically controlled brake valve for a drone

Abstract

A method for controlling an electronically controlled brake valve for an unmanned aerial vehicle includes pressure closed-loop control, wherein a difference a is obtained between a brake command and a brake pressure. If the difference exceeds a first threshold range, the electronically controlled brake valve outputs a first control signal to a brake actuator. A difference b is obtained between the first control signal and a drive current signal. If the difference exceeds a second threshold range, the electronically controlled brake valve outputs a second control signal to the brake actuator; if the difference does not exceed the second threshold range, the first control signal is assigned to the second control signal. A difference c is obtained between the second control signal and a brake valve core flow rate. If the difference exceeds a third threshold, the electronically controlled brake valve outputs a third control signal to the brake actuator; if the difference does not exceed the third threshold, the second control signal is assigned to the third control signal. The third control signal controls the wheel speed, obtains a wheel speed signal, and performs anti-yaw control according to the wheel speed difference signal. The present invention realizes redundancy control of the electronically controlled brake valve and heading correction within a small angle, thereby enhancing the reliability and safety of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of brake control, and in particular to a method for controlling an electronically controlled brake valve for an unmanned aerial vehicle. Background Art

[0002] At present, the UAV hydraulic brake control system is still the mainstream direction of the current UAV wheel brake control system design. The electronically controlled brake valve, as the core braking device in the hydraulic brake control system, plays a vital role in the system. By adjusting the brake pressure, it ensures the landing safety of the UAV under various working conditions.

[0003] After the drone lands, the electromechanical processor outputs a brake command signal to the electronically controlled brake valve. Simultaneously, the electronically controlled brake valve receives the wheel speed signal from the wheel speed sensor and the brake pressure signal from the pressure sensor. Based on this, it generates the corresponding braking stroke through closed-loop control, pushing the actuator to output the corresponding brake pressure to achieve drone braking (static braking, normal braking, corrective braking, brake release, etc.). As a key component of the electronically controlled brake valve, the control method of the electronically controlled brake valve plays a vital role in the braking process. The safety and reliability of the electronically controlled brake valve control method will directly affect the safety of the drone's takeoff and landing, as well as the field failure rate.

[0004] Currently, the mainstream control method for electronically controlled brake valves is "pressure closed-loop" control. Electronically controlled brake valves dynamically and hysteretically adjust the brake command information output by the electromechanical processor and the brake pressure information returned by the pressure sensor. When the difference between the brake pressure returned by the pressure sensor and the brake command output by the electromechanical processor is within the ±δ (threshold) range, the wheel brake control system determines that the system brake pressure and the command information issued by the electromechanical processor are dynamically balanced, and no actuator stroke adjustment is required. When the difference between the brake pressure returned by the pressure sensor and the brake command output by the electromechanical processor is outside the ±δ (threshold) range, the wheel brake system determines that the system brake pressure and the command signal issued by the electromechanical processor are not dynamically balanced. In this case, the brake actuator stroke is controlled forward or backward, and dynamic adjustment is performed to rebalance the brake pressure and brake command. While existing electronically controlled brake valve control methods can effectively achieve wheel brake control, their "single closed-loop" control and normal system control deviations can lead to a loss of control accuracy and reduced braking efficiency.

[0005] The above-mentioned existing electronic brake valve control method has the following disadvantages: first, when the UAV brakes at high speed, it is very likely to produce a heading deviation angle due to the loss of control accuracy, causing the UAV to deviate from the heading; second, the existing control method cannot quickly achieve heading correction within a small angle; third, since the "single closed-loop" control is a single redundancy control design, there is a large risk of failure, which greatly reduces the safety of the wheel brake control system. Summary of the Invention

[0006] In order to improve the control accuracy of the electronically controlled brake valve for UAVs, realize the redundancy control of the electronically controlled brake valve and the heading correction within a small angle, and enhance the reliability and safety of the wheel brake control system, the present invention proposes a control method for the electronically controlled brake valve for UAVs.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for controlling an electronically controlled brake valve for a drone comprises the following steps:

[0009] Step 1: Pressure closed-loop control. The difference a between the brake command output by the electromechanical processor and the brake pressure returned by the pressure sensor is calculated and compared with a preset first threshold. If the difference exceeds the first threshold, the electronically controlled brake valve outputs a first control signal to the brake actuator. If the difference does not exceed the first threshold, the brake pressure and the brake command are dynamically balanced.

[0010] Step 2, current closed-loop control, calculates the difference b between the first control signal obtained in step 1 and the drive current signal, and compares it with a preset second threshold. If it exceeds the second threshold range, the electronically controlled brake valve outputs a second control signal to the brake actuating device; if it does not exceed the second threshold range, the first control signal output in step 1 is assigned to the second control signal;

[0011] Step 3: Flow closed-loop control. The difference c between the second control signal obtained in step 2 and the brake valve core flow rate is compared with a preset third threshold. If the difference exceeds the third threshold, the electronically controlled brake valve outputs a third control signal to the brake actuating device. If the difference does not exceed the third threshold, the second control signal output in step 2 is assigned to the third control signal.

[0012] Step 4: "PD+PBM" bias control, the third control signal controls the wheel speed, obtains the wheel speed signal, and performs anti-yaw control based on the wheel speed difference signal.

[0013] The specific process of step 1 is to normalize the brake command and the brake pressure, calculate the difference a between the normalized brake command and the brake pressure, compare it with a preset first threshold range, determine whether the brake actuator needs to be actuated to adjust the ball screw stroke, and output the brake command as the first control signal;

[0014] When the difference a is within the first threshold range of ±δ1, the brake pressure and the brake command are dynamically balanced, and there is no need to adjust the ball screw stroke;

[0015] When the difference a is outside the first threshold range of ±δ1, the brake pressure and the brake command have not reached dynamic balance, and the first control signal is output to control the ball screw stroke forward or backward, and dynamically adjust the brake pressure and the brake command to reach a new balance.

[0016] The specific process of step 2 is to obtain the driving current signal returned by the current sensor, normalize the driving current signal, calculate the difference b between the first control signal obtained in step 1 and the normalized driving current signal, and compare the difference with a preset second threshold range to determine whether the brake actuator needs to be activated to adjust the ball screw stroke;

[0017] When the difference b is within the second threshold range of ±δ2, the drive current signal and the brake command reach a dynamic balance in the system current domain, and there is no need to further adjust the ball screw stroke. The first control signal output in step 1 is assigned to the second control signal;

[0018] When the difference b is outside the second threshold range of ±δ2, the drive current signal and the brake command have not reached a dynamic balance in the system current domain, and a second control signal is output to further control the ball screw stroke forward or backward, and dynamically adjust the drive current signal and the brake command to reach a new balance.

[0019] The specific process of step 3 is to obtain the brake valve core flow rate based on the valve core position and the hydraulic flow rate, normalize the brake valve core flow rate, calculate the difference c between the second control signal obtained in step 2 and the normalized brake valve core flow rate, and compare it with a preset third threshold range to determine whether the brake actuator needs to be activated to adjust the ball screw stroke;

[0020] When the difference c is within the third threshold range of ±δ3, the brake valve core flow and the brake command reach a dynamic balance in the system flow domain, and there is no need to adjust the ball screw stroke. The second control signal output in step 2 is assigned to the third control signal;

[0021] When the difference c is outside the third threshold range of ±δ3, the brake valve core flow and the brake command have not reached a dynamic balance in the system flow domain, and a third control signal is output to further control the ball screw stroke forward or backward, and dynamically adjust the valve core flow and the brake command to reach a new balance.

[0022] The specific process of step 4 is as follows: judging based on the collected wheel speed signal, when the speed difference between the wheel speed on one side and the wheel speed on the other side reaches a threshold value Vd1, reducing the voltage of the electronically controlled brake valve on the low-speed side, releasing the brake pressure on the low-speed side, and rapidly increasing the wheel speed on the low-speed side, thereby preventing the aircraft from deviation and activating the anti-yaw control function; when the above speed difference is less than the threshold value Vd2, the anti-yaw control function automatically fails.

[0023] The normalization is to normalize the information dimensionlessly.

[0024] The beneficial effects of the present invention are:

[0025] On the basis of existing control signals, the present invention introduces wheel speed signals, drive line current signals and electronically controlled brake valve core displacement signals, and implements a bias control strategy based on "PD+PBM" to achieve wheel redundancy, precise braking and heading correction control, thereby increasing the reliability and safety of the wheel braking system. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Flow chart of the method of the present invention. DETAILED DESCRIPTION

[0027] The present invention will be described in further detail below with reference to the accompanying drawings.

[0028] The execution components involved in the wheel brake control system to which this embodiment is applicable but not limited include: an electromechanical processor, a wheel speed sensor, a current sensor, a displacement sensor, a pressure sensor, an electronically controlled brake valve, etc.

[0029] First, the working status of the wheel brake system is determined. The electromechanical processor in the wheel brake system sends a power-on BIT fault detection signal. Each component in the wheel brake system responds to the power-on BIT fault detection signal and generates a feedback signal. The electromechanical processor receives the feedback signal. If the wheel brake system has no faults, the electronically controlled brake valve responds to the instructions issued by the electromechanical processor and works. If the wheel brake system has a fault, the electronically controlled brake valve does not respond to the instructions issued by the electromechanical processor and works.

[0030] After confirming that the wheel brake system has no faults, the control method of the present application is implemented.

[0031] Example 1

[0032] A method for controlling an electronically controlled brake valve for a drone comprises the following steps:

[0033] Step 1: Pressure closed-loop control: The electronically controlled brake valve dynamically and hysteretically adjusts the brake command output by the electromechanical processor and the brake pressure returned by the pressure sensor. The brake command and brake pressure are normalized to normalize the dimensions of the collected information to improve system control accuracy. The difference a between the normalized brake command and brake pressure is calculated and compared with a preset threshold range to determine whether the actuator needs to be activated.

[0034] When the difference a is within the ±δ1 threshold, the brake pressure is dynamically balanced with the brake command issued by the electromechanical processor, and there is no need to adjust the ball screw stroke. The brake command is output as the control signal P1;

[0035] When the difference a is outside the ±δ1 threshold range, the brake pressure and the brake command issued by the electromechanical processor have not reached dynamic equilibrium. At this time, a control signal P1 is output to the brake actuator to control the ball screw to move forward or backward, and dynamically adjust the brake pressure and the brake command signal to reach a new balance.

[0036] Step 2, current closed-loop control: obtain the driving current signal sent back by the current sensor, normalize the driving current signal, and calculate the difference b between the brake actuator control signal P1 obtained in step 1 and the normalized driving current signal;

[0037] When the difference b is within the ±δ2 threshold, the drive current signal and the brake command signal issued by the electromechanical processor reach a dynamic balance in the system current domain. No further adjustment of the ball screw stroke is required. The system adopts the control result of step 1 and assigns the brake actuator control signal P1 output in step 1 to P2.

[0038] When the difference b is outside the ±δ2 threshold range, the drive current signal and the brake command signal issued by the electromechanical processor have not reached a dynamic balance in the system current domain. At this time, a control signal P2 is output to the brake actuator to further control the ball screw stroke forward or backward, and dynamically adjust the drive current and the brake command signal to reach a new balance;

[0039] Step 3, flow closed-loop control: obtain the brake valve core flow according to the valve core position and the hydraulic flow, normalize the brake valve core flow, and calculate the difference c between the brake actuator control signal P2 obtained in step 2 and the normalized brake valve core flow;

[0040] When the difference c is within the ±δ3 threshold, the brake valve core flow and the brake command issued by the electromechanical processor reach a dynamic balance in the system flow domain. There is no need to adjust the ball screw stroke. The system adopts the control result of step 2 and assigns the brake actuator control signal P2 output in step 2 to P3.

[0041] When the difference c is outside the ±δ3 threshold range, the brake spool flow rate and the brake command issued by the electromechanical processor have not reached a dynamic balance in the system flow domain. At this time, a control signal P3 is output to the brake actuator to control the ball screw stroke forward or backward, and dynamically adjust the spool flow rate and the brake command to reach a new balance;

[0042] Step 4: "PD+PBM" bias control: Bias control involves hysteresis adjustment between the brake actuator control signal P3 output from step 3 and the wheel speed difference signal returned by the wheel speed sensor. The magnitude and rise and fall pattern of the brake actuator control signal are modulated based on the amplitude, duration, and frequency of the wheel speed difference signal.

[0043] Based on the collected wheel speed signals, when the speed difference between the wheel speeds on one side and the other side reaches the threshold value Vd1, the anti-yaw control function is used to reduce the brake valve voltage on the low-speed side, releasing the brake pressure on that side, causing the wheel speed on the low-speed side to increase rapidly, thereby preventing the aircraft from running off the track; when the above speed difference is less than the threshold value Vd2, the anti-yaw control function automatically fails.

[0044] Example 2

[0045] A method for controlling an electronically controlled brake valve for a drone comprises the following steps:

[0046] Step 1: The electronically controlled brake valve performs PID closed-loop control based on the brake command output by the received electromechanical processor and the brake pressure sent back by the pressure sensor; the brake command is a (0~20)mA current signal, corresponding to the brake command (0~8)MPa, and the corresponding pressure sensor returns a current of (4~21)mA.

[0047] The pressure closed-loop control response is as follows:

[0048] 1) The brake command is set to 20mA current. The electronically controlled brake valve outputs a corresponding brake command of 6.8MPa according to the brake command. The pressure sensor returns a brake pressure of 18.2mA, which is lower than the lower limit of the pressure closed loop of 7.2Mpa. The pressure closed loop is started, and the difference between the brake command and the recovered brake pressure is controlled by PID closed loop. After reaching a new balance, the electronically controlled brake valve outputs a corresponding brake command of 7.4MPa, and the pressure sensor returns a brake pressure of 20.1mA.

[0049] 2) The brake command is set to a current of 20mA. The electronically controlled brake valve outputs a corresponding brake pressure of 9.5MPa according to the brake command. The pressure sensor returns a brake pressure of 23.9mA, which is higher than the upper limit of the pressure closed loop of 8.8Mpa. The pressure closed loop is started, and PID closed-loop control is performed on the difference between the brake command and the recovered brake pressure. After reaching a new balance, the electronically controlled brake valve outputs a corresponding brake command of 8.6MPa, and the pressure sensor returns a brake pressure of 22.2mA.

[0050] 3) The brake command is set to 20mA current. The electronically controlled brake valve outputs the corresponding brake pressure of 8.4MPa according to the brake command. The pressure sensor returns the brake pressure of 21.6mA. Within the upper and lower limit thresholds of the pressure closed loop, the equilibrium state has been reached and the pressure closed loop control is not started.

[0051] Step 2, current closed loop response

[0052] The electronically controlled brake valve performs PID closed-loop control according to the brake command output in step 1 and the drive line current signal sent back by the current sensor. The brake command signal range is (0-10) MPa, and the corresponding current sensor returns a current of (2-12) V.

[0053] In this embodiment, the current closed-loop control response is as follows:

[0054] 1) The brake command output in step 1 reaches 8 MPa. The electronically controlled brake valve outputs a corresponding brake pressure of 7.3 MPa according to the brake command. The current sensor returns a driving current signal of 9.3 V, which is lower than the current closed-loop lower limit of 7.5 MPa. The current closed-loop is started, and PID closed-loop control is performed on the difference between the output command of the pressure closed-loop and the returned driving current signal. After reaching a new balance, the electronically controlled brake valve outputs a corresponding brake pressure of 7.6 MPa according to the brake command, and the current sensor returns a driving current signal of 9.6 V.

[0055] 2) The brake command output in step 1 reaches 8 MPa. The electronically controlled brake valve outputs the corresponding brake pressure of 8.7 MPa according to the brake command. The current sensor returns a driving current signal of 10.7 V, which is higher than the current closed-loop upper limit of 8.5 MPa. The current closed-loop is started, and PID closed-loop control is performed on the difference between the output command of the pressure closed-loop and the recovered driving current signal. After reaching a new balance, the electronically controlled brake valve outputs the corresponding brake pressure of 8.3 MPa according to the brake command, and the current sensor returns a driving current signal of 10.3 V.

[0056] 3) The brake command output in step 1 reaches 8 MPa. The electronically controlled brake valve outputs the corresponding brake pressure of 8.2 MPa according to the brake command. The current sensor returns a driving current signal of 10.2 V. Within the upper and lower limit thresholds of the current closed loop, dynamic balance has been achieved, and the current closed loop control is not started.

[0057] Step 3: Flow closed-loop response

[0058] The electronically controlled brake valve performs PID closed-loop control on the brake valve core flow rate calculated based on the brake command information output in step 2 and the valve core position information returned by the displacement sensor. The brake command signal range is (0~10)Mpa, and the corresponding displacement sensor returns a displacement of (4~14)V.

[0059] In this embodiment, the flow closed-loop control response is as follows:

[0060] 1) The brake command output in step 2 is 8 MPa. The electronically controlled brake valve outputs a corresponding brake pressure of 7.6 MPa according to the brake command. The displacement sensor returns the valve core displacement of 11.6 V, which is lower than the flow closed loop lower limit of 7.8 MPa. The flow closed loop is started, and the PID closed loop control is performed on the difference between the output command of the current closed loop and the displacement signal of the return valve core. After reaching a new balance, the electronically controlled brake valve outputs a corresponding brake pressure of 8.1 MPa according to the brake command, and the displacement sensor returns a displacement signal of 12.1 V.

[0061] 2) The brake command output in step 2 reaches 8 MPa. The electronically controlled brake valve outputs the corresponding brake pressure of 8.4 MPa according to the brake command. The displacement sensor returns the valve core displacement of 12.4 V, which is higher than the flow closed loop upper limit of 8.2 MPa. The flow closed loop is started, and the PID closed loop control is performed on the difference between the output command of the current closed loop and the displacement signal of the return valve core. After reaching a new balance, the electronically controlled brake valve outputs the corresponding brake pressure of 8.0 MPa according to the brake command, and the displacement sensor returns a displacement signal of 12.0 V.

[0062] 3) The brake command output in step 2 reaches 8 MPa. The electronically controlled brake valve outputs the corresponding brake pressure of 7.9 MPa according to the brake command. The displacement sensor returns a valve core displacement signal of 11.9 V. Within the upper and lower limit thresholds of the flow closed loop, dynamic balance has been achieved, and the flow closed loop control is not started.

[0063] Step 4: Small Angle Correction Response

[0064] "PD+PBM" bias control achieves small-angle heading correction by dynamically adjusting the brake pressure output from step 3 with the wheel speed information returned by the wheel speed sensor. This control method modulates the brake pressure level and its rise and fall pattern based on the amplitude, duration, and frequency of the wheel speed difference signal, demonstrating a certain degree of adaptive brake pressure regulation.

[0065] In this embodiment, the “PD+PBM” bias control response is as follows:

[0066] 1) With both left and right wheel speeds set to 200 km / h and the brake command set to 20 mA, and no wheel slippage occurring, the electronically controlled brake valves output the corresponding brake current according to the given brake command. The left and right electronically controlled brake valves output brake pressures of 7.9 MPa, respectively. No heading deviation occurs, and the correction function is not activated.

[0067] 2) The left and right wheel speeds are set to 200 km / h at the same time, and the brake command is set to 20 mA current. When the left wheel slips due to the change in the runway binding coefficient, when the left wheel speed drops to 30 km / h, the UAV's heading will deviate to the left, forcibly triggering the "PD+PBM" bias control to perform anti-skid correction on the left wheel, releasing the left brake pressure, and reducing the left brake pressure to 3 MPa, causing the wheel on this side to change from sliding to rolling. At the same time, the left wheel speed is assigned to the right wheel speed, triggering the anti-skid correction function of the right wheel, actively releasing the right brake pressure, and the right electric brake pressure is synchronously reduced to 3 MPa. Finally, the left and right wheel brake pressures slowly rise to the output pressure value of 7.9 MPa corresponding to the command, ensuring the synchronization of the left and right wheel speeds and correcting the aircraft heading.

[0068] 3) The left and right wheel speeds are set to 200 km / h at the same time, and the brake command is set to 20 mA current. When the right wheel slips due to the change in the runway binding coefficient, when the right wheel speed drops to 30 km / h, the UAV's heading will deviate to the right, forcibly triggering the "PD+PBM" bias control to perform anti-skid correction on the right wheel, releasing the right brake pressure, and reducing the right brake pressure to 3 MPa, causing the wheel on this side to change from sliding to rolling state; at the same time, the right wheel speed is assigned to the left wheel speed, triggering the anti-skid correction function of the left wheel, actively releasing the left brake pressure, and the left electric brake pressure is synchronously reduced to 3 MPa. Finally, the left and right wheel brake pressures slowly rise to the output pressure value of 7.9 MPa corresponding to the command, ensuring the synchronization of the left and right wheel speeds and correcting the aircraft heading.

[0069] In this embodiment, by gradually increasing the pressure closed-loop control, current closed-loop control and flow closed-loop control, the brake pressure is monitored and gradually approaches the brake command, and when any closed-loop fails, it does not affect the braking of the drone. The result is consistent with expectations, and the goal of improving the control accuracy and redundancy control of the electronically controlled brake valve is achieved; in this embodiment, by changing the input conditions of the hydraulic brake system, whether the drone yaws is monitored, and once yawed, the aircraft heading is corrected in real time. The result is consistent with expectations, and the goal of correcting the aircraft's small-angle heading deviation is achieved, thereby improving the reliability and safety of the hydraulic brake system.

[0070] The parts not described in detail in this embodiment are commonly known in the industry and are not described here one by one. The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same or similar to the present invention fall within the scope of protection of the present invention.

Claims

1. A method for controlling an electronically controlled brake valve for a drone, characterized in that: The following steps are involved: Step 1: Pressure closed-loop control. The difference a between the brake command output by the electromechanical processor and the brake pressure returned by the pressure sensor is calculated and compared with a preset first threshold. If the difference exceeds the first threshold, the electronically controlled brake valve outputs a first control signal to the brake actuator. If the difference does not exceed the first threshold, the brake pressure and the brake command are dynamically balanced. The specific process of step 1 is to normalize the brake command and the brake pressure, calculate the difference a between the normalized brake command and the brake pressure, compare it with a preset first threshold range, and determine whether the brake actuator needs to be activated to adjust the ball screw stroke; When the difference a is within the first threshold range of ±δ1, the brake pressure and the brake command are dynamically balanced, and there is no need to adjust the ball screw stroke. The brake command is output as the first control signal; When the difference a is outside the first threshold range of ±δ1, the brake pressure and the brake command have not reached dynamic equilibrium, and a first control signal is output to control the ball screw to move forward or backward, and dynamically adjust the brake pressure and the brake command to reach a new balance; Step 2, current closed-loop control, calculates the difference b between the first control signal obtained in step 1 and the drive current signal, and compares it with a preset second threshold. If it exceeds the second threshold range, the electronically controlled brake valve outputs a second control signal to the brake actuating device; if it does not exceed the second threshold range, the first control signal output in step 1 is assigned to the second control signal; Step 3: Flow closed-loop control. The difference c between the second control signal obtained in step 2 and the brake valve core flow rate is compared with a preset third threshold. If the difference exceeds the third threshold, the electronically controlled brake valve outputs a third control signal to the brake actuating device. If the difference does not exceed the third threshold, the second control signal output in step 2 is assigned to the third control signal. Step 4, "PD+PBM" bias control, the third control signal controls the wheel speed, obtains the wheel speed signal, and performs anti-yaw control based on the wheel speed difference signal.

2. The method for controlling an electronically controlled brake valve for a drone according to claim 1, wherein: The specific process of step 2 is to obtain the driving current signal returned by the current sensor, normalize the driving current signal, calculate the difference b between the first control signal obtained in step 1 and the normalized driving current signal, and compare the difference with a preset second threshold range to determine whether the brake actuator needs to be activated to adjust the ball screw stroke; When the difference b is within the second threshold range of ±δ2, the drive current signal and the brake command reach a dynamic balance in the system current domain, and there is no need to further adjust the ball screw stroke. The first control signal output in step 1 is assigned to the second control signal; When the difference b is outside the second threshold range of ±δ2, the drive current signal and the brake command have not reached a dynamic balance in the system current domain, and a second control signal is output to further control the ball screw stroke forward or backward, and dynamically adjust the drive current signal and the brake command to reach a new balance.

3. The method for controlling an electronically controlled brake valve for a UAV according to claim 2, characterized in that: The specific process of step 3 is to obtain the brake valve core flow rate based on the valve core position and the hydraulic flow rate, normalize the brake valve core flow rate, calculate the difference c between the second control signal obtained in step 2 and the normalized brake valve core flow rate, and compare it with a preset third threshold range to determine whether the brake actuator needs to be activated to adjust the ball screw stroke; When the difference c is within the third threshold range of ±δ3, the brake valve core flow and the brake command reach a dynamic balance in the system flow domain, and there is no need to adjust the ball screw stroke. The second control signal output in step 2 is assigned to the third control signal; When the difference c is outside the third threshold range of ±δ3, the brake valve core flow and the brake command have not reached a dynamic balance in the system flow domain, and a third control signal is output to further control the ball screw stroke forward or backward, and dynamically adjust the valve core flow and the brake command to reach a new balance.

4. The method for controlling an electronically controlled brake valve for a UAV according to claim 3, characterized in that: The specific process of step 4 is as follows: judging based on the collected wheel speed signal, when the speed difference between the wheel speed on one side and the wheel speed on the other side reaches a threshold value Vd1, reducing the voltage of the electronically controlled brake valve on the low-speed side, releasing the brake pressure on the low-speed side, and rapidly increasing the wheel speed on the low-speed side, thereby preventing the aircraft from deviation and activating the anti-yaw control function; when the above speed difference is less than the threshold value Vd2, the anti-yaw control function automatically fails.

5. The method for controlling an electronically controlled brake valve for a UAV according to claim 3, characterized in that: The normalization is to normalize the information dimensionlessly.

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