A flight control method and system based on multi-information collaborative control

Abstract

The present invention discloses a flight control method and system based on multi-information collaborative control, the method comprising: a flight computer acquires each sensor signal and a predetermined target position, initializes an ideal trajectory of an aircraft and acquires an ideal position of the aircraft; calculates GNSS and IMU failure detection factors, and determines the actual position of the aircraft according to the failure detection results of GNSS signals and IMU signals; when the distance between the actual position of the aircraft and the predetermined target position is greater than a distance threshold, for the case where the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculates the deviation time interval and the adaptive optimization time, and obtains the aircraft correction acceleration, otherwise continues to monitor each signal parameter; when the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, the target is screened by infrared image. The present invention combines signal failure detection, correction algorithm optimization and pixel temperature screening to achieve precise navigation of the aircraft.

Description

Technical Field

[0001] The present invention relates to the field of flight control technology, and in particular to a flight control method and system based on multi-information collaborative control. Background Art

[0002] In traditional aircraft control methods, usually only aircraft GNSS signals or aircraft IMU signals are used to guide and control the flight trajectory to ensure that the landing position of the aircraft meets expectations and reaches the predetermined target. Once these signals have problems, it will cause unpredictable consequences for the tasks being performed. Therefore, it is necessary to detect the failure of the signal before using it and provide feasible remedial measures for the specific failure situation. In addition, due to the remoteness and limitation of aircraft control, there will be a deviation between the actual landing position of the aircraft and the predetermined target position. Although the traditional method uses data processing + track adjustment to correct the deviation, it does not take into account that the length of time used in the deviation correction process will also affect the aircraft. Once the deviation correction time is too long and the correction speed is too slow, the correction efficiency will be reduced, affecting the subsequent correction. Or if the deviation correction time is too short and the correction speed is too fast, the rapid change in speed will easily affect the flight stability of the aircraft. Multiple inaccurate adjustments will seriously affect the final control effect of the aircraft. Therefore, researchers in this field need to propose a more comprehensive aircraft control method to solve the above problems. Summary of the invention

[0003] The present invention provides a flight control method and system based on multi-information collaborative control to solve the technical problems of the current flight control method, such as lack of signal failure detection, poor position correction effect and low landing accuracy.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] In one aspect, the present invention provides a flight control method based on multi-information coordinated control, comprising the following steps:

[0006] S1. The flight computer obtains the aircraft's GNSS position, the aircraft's IMU position, the aircraft's infrared detector signal and the predetermined target position, initializes the aircraft's ideal trajectory, and obtains the aircraft's ideal position;

[0007] S2. Initialize the failure detection factor threshold, calculate the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculate the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, compare the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, and determine the actual position of the aircraft according to the failure detection results of the GNSS signal and the IMU signal;

[0008] S3, initialize the distance threshold, calculate the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initialize the position deviation threshold, calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculate the deviation time interval and the adaptive optimization time, and obtain the aircraft correction acceleration, otherwise continue to monitor the signal parameters;

[0009] S4. When the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, the predetermined target is screened by the temperature of each pixel point on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the pixel points corresponding to each suspicious target are calculated to determine the predetermined target;

[0010] S5. Lock and track the predetermined target to complete the aircraft navigation.

[0011] Furthermore, the step S1 includes the following steps:

[0012] The flight computer obtains the aircraft's GNSS position ,in

[0013] , The x-axis coordinate of the aircraft's GNSS position. The y-axis coordinate of the aircraft's GNSS position. The z-axis coordinate representing the aircraft's GNSS position;

[0014] The flight computer obtains the aircraft IMU position ,in , Indicates the x-axis coordinate of the aircraft IMU position, Indicates the y-axis coordinate of the aircraft IMU position, Indicates the z-axis coordinate of the aircraft IMU position;

[0015] The flight computer acquires the aircraft's infrared detector signal;

[0016] The flight computer acquires the predetermined target position ,in , represents the x-axis coordinate of the intended target position, represents the y-axis coordinate of the intended target position, The z-axis coordinate representing the predetermined target position;

[0017] Initialize the ideal trajectory of the aircraft and obtain the ideal position of the aircraft ,in , The x-axis coordinate representing the ideal position of the aircraft, The y-axis coordinate representing the ideal position of the aircraft, The z-axis coordinate representing the ideal position of the aircraft;

[0018] It should be noted that the flight computer in the present invention refers to the control computer of the aircraft, which is used to monitor various parameters of the aircraft and issue various commands.

[0019] Furthermore, the step S2 comprises the following steps:

[0020] Initialize the failure detection factor threshold , S represents failure detection;

[0021] Calculate the GNSS failure detection factor based on the aircraft GNSS position and the aircraft ideal position , GNSS failure detection factor at the i-th moment The expression is as follows:

[0022] ;

[0023] in, represents the x-axis coordinate of the aircraft GNSS position at the i-th moment, represents the y-axis coordinate of the aircraft GNSS position at the i-th moment, represents the z-axis coordinate of the aircraft GNSS position at the i-th moment, represents the x-axis coordinate of the ideal position of the aircraft at the i-th moment, represents the y-axis coordinate of the ideal position of the aircraft at the i-th moment, The z-axis coordinate of the ideal position of the aircraft at the i-th moment;

[0024] Calculate the IMU failure detection factor based on the aircraft IMU position and the aircraft ideal position , IMU failure detection factor at the i-th moment The expression is as follows:

[0025] ;

[0026] in, represents the x-axis coordinate of the aircraft IMU position at the i-th moment, represents the y-axis coordinate of the aircraft IMU position at the i-th moment, Represents the z-axis coordinate of the aircraft IMU position at the i-th moment;

[0027] when , it means that the aircraft GNSS position and aircraft IMU position at the i-th moment are both valid. At this time, the actual position of the aircraft at the i-th moment is the GNSS position of the aircraft at the i-th moment;

[0028] when , it means that the GNSS position of the aircraft at the i-th moment is valid but the IMU position of the aircraft is invalid. The IMU position of the aircraft is corrected. At this time, the actual position of the aircraft at the i-th moment is is the GNSS position of the aircraft at the i-th moment;

[0029] It should be noted that the correction of the aircraft IMU position means that the deviation between the aircraft IMU position and the ideal position of the aircraft is too large, so the aircraft actual position and aircraft speed at the previous moment can be used to correct the aircraft IMU position;

[0030] when , it means that the GNSS position of the aircraft at the i-th moment is invalid but the IMU position of the aircraft is valid. At this time, the actual position of the aircraft at the i-th moment is is the IMU position of the aircraft at the i-th moment;

[0031] when When the GNSS position and IMU position of the aircraft at the i-th moment are both invalid, the flight computer sends an alarm message to the aircraft command center for manual intervention, and uses the velocity and acceleration information of the previous moment to calculate the actual position of the aircraft at the i-th moment. ;

[0032] It should be noted that the present invention does not consider the situation where signal failure is detected due to the similarity of the multiplied values ​​of the changes in the x-axis, y-axis and z-axis. Although this situation does exist, since the GNSS signal and IMU signal are monitored in real time, even if this situation occurs, the influence of this interference can be eliminated in the subsequent correction stage. Through failure detection, the mission failure of the aircraft due to signal failure during the navigation process can be avoided, thereby improving the fault tolerance and landing accuracy of the present technical solution.

[0033] Furthermore, step S3 includes the following steps:

[0034] Initialize distance threshold ;

[0035] Calculate the distance between the actual position of the aircraft and the predetermined target position , where the distance between the actual position of the aircraft and the predetermined target position at the i-th moment is The expression is as follows:

[0036] ;

[0037] in, represents the x-axis coordinate of the actual position of the aircraft at the i-th moment, represents the y-axis coordinate of the actual position of the aircraft at the i-th moment, represents the z-axis coordinate of the actual position of the aircraft at the i-th moment, represents the x-axis coordinate of the target position at the i-th moment, represents the y-axis coordinate of the target position at the i-th moment, represents the z-axis coordinate of the target position at the i-th moment;

[0038] when When the flight computer processes only GNSS and IMU signals, it does not process the aircraft's infrared detector signals;

[0039] Initialize position deviation threshold ;

[0040] Calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft , where the deviation between the actual position of the aircraft and the ideal position of the aircraft at the i-th moment is The expression is as follows:

[0041] ;

[0042] when When , calculate the deviation time interval and adaptive optimization time to obtain the corrected acceleration of the aircraft;

[0043] It should be noted that when the flight computer obtains the parameters of the aircraft's corrective acceleration, it will adjust the aircraft's acceleration by adjusting the engine thrust direction and the control surface deflection angle;

[0044] when The flight computer continues to monitor the GNSS and IMU signals.

[0045] Furthermore, the calculation of the deviation time interval and the adaptive optimization time in step S3 to obtain the aircraft correction acceleration includes the following steps:

[0046] Traverse the historical moments before the i-th moment in turn and calculate the deviation of each historical moment , if at the jth moment Greater than 0.1 , then the deviation time interval can be obtained ;

[0047] Calculate the number of positions in the deviation time interval ,in ;

[0048] Initialization time deviation threshold , the expression of adaptive optimization time T is as follows:

[0049] when When ;

[0050] when When ;

[0051] The flight computer obtains the relationship between the x-axis position deviation, y-axis position deviation and z-axis position deviation at the i-th moment and the x-axis direction correction acceleration, y-axis direction correction acceleration and z-axis direction correction acceleration respectively, where the relationship between the i-th moment and the The expression of the above relationship at this moment is as follows:

[0052] ;

[0053] in, Indicates the corrected acceleration in the x-axis direction, Indicates the corrected acceleration in the y-axis direction, Indicates the corrected acceleration in the z-axis direction, represents the ideal speed of the aircraft on the x-axis at the i-th moment, represents the actual speed of the aircraft on the x-axis at the i-th moment, represents the ideal speed of the aircraft on the y-axis at the i-th moment, represents the actual speed of the aircraft on the y-axis at the i-th moment, represents the ideal speed of the aircraft on the z-axis at the i-th moment, represents the actual speed of the aircraft on the z-axis at the i-th moment;

[0054] Obtained by the following formula and :

[0055] ;

[0056] In the Time to At the moment, the corrected acceleration in the x-axis direction is , the corrected acceleration in the y-axis direction is , the corrected acceleration in the z-axis direction is ;

[0057] It should be noted that by setting the adaptive optimization time, the correction requirements of deviations generated under different conditions can be met to avoid the effect of too fast correction on the flight stability of the aircraft or too slow correction on the correction efficiency. This can ensure the correction of deviations while minimizing interference with the flight process. In addition, the adaptive optimization time is divided into two correction stages, and the correction accelerations in the two stages are the same in magnitude but opposite in direction, so that after the position deviation is corrected, the speed that causes the deviation is also corrected, that is, the deviation speed in the corresponding direction is zero, which can avoid repeated deviations and further improve the calculation efficiency of the algorithm. The proportional division of the correction stages in the adaptive optimization time mainly depends on the empirical value. Since the time must be an integer, Just round up to the nearest integer.

[0058] Furthermore, the step S4 comprises the following steps:

[0059] (1) When When the aircraft infrared detector signals are detected, the flight computer processes the aircraft infrared detector signals and generates infrared images from the aircraft infrared detector signals;

[0060] (2) Initialization temperature threshold , traverse each pixel on the infrared image, count the number of pixels with temperatures higher than the temperature threshold and record them as the number of suspicious pixels;

[0061] (3) If the number of suspicious pixels is 1, the pixel is directly locked as the predetermined target. If the number of suspicious pixels is greater than 1, there are interference points and further screening is required;

[0062] (4) If the number of suspicious pixels is greater than 1, calculate the temperature confidence U of each suspicious pixel, where the temperature confidence of the kth suspicious pixel is , the expression is as follows:

[0063] ;

[0064] in, Represents the temperature value of the kth suspicious pixel, Represents the number of pixels around the kth suspicious pixel, Indicates the maximum temperature of the pixel in the infrared image. Indicates the minimum value of the pixel temperature in the infrared image;

[0065] Calculate the gray confidence H of each suspicious target, where the gray confidence of the kth suspicious pixel is , the expression is as follows:

[0066] ;

[0067] in, represents the gray value of the kth suspicious pixel, Indicates the maximum value of the grayscale of the pixel in the infrared image. Indicates the minimum gray value of the pixel in the infrared image;

[0068] (5) Initialize temperature confidence threshold and gray confidence threshold , if the temperature confidence of the suspicious pixel in the current frame of the infrared image is greater than the temperature confidence threshold and the gray confidence is greater than the gray confidence threshold, then the flag FLAG of the suspicious pixel is increased by 1, and 5 frames are taken continuously. If the FLAG of the suspicious pixel is 5, the suspicious pixel is determined to be the predetermined target, otherwise it is an interference point. If there are still multiple suspicious pixels with FLAG of 5 at this time, the K-means clustering method is used to cluster the above suspicious pixels. If it is determined that all suspicious pixels are of the same type, it indicates that the volume of the predetermined target is too large and occupies multiple pixels. The pixel at the center of the cluster is taken as the center of the predetermined target and locked and tracked. Otherwise, the number of frames taken is continued to increase for detection until the only suspicious pixel is distinguished. If the predetermined target is not found in the infrared image, frames are continuously taken for detection until the predetermined target is found and locked and tracked;

[0069] It should be noted that in order to reserve enough maneuvering time and space, the aircraft must start searching for the intended target at a certain distance. Under this distance condition, the intended target observed in the infrared image usually only occupies one pixel. If there are multiple suspicious pixels, two situations are considered: one is that there are interfering targets around the intended target that interfere with the aircraft identification, and the other is that the intended target itself is too large and occupies more pixels. The pixels of the former are more scattered, and the pixels of the latter are more concentrated. At this time, the K-means clustering algorithm can be used to determine the specific situation. For the former, the technical solution uses temperature confidence and grayscale confidence to eliminate the influence of interfering targets in time. For the latter, the technical solution tracks the center point of the intended target to achieve the optimal guidance effect. Through the above process, the intended target can be locked more accurately, thereby improving the landing accuracy.

[0070] Furthermore, the step S5 comprises the following steps:

[0071] After the aircraft locks and tracks the predetermined target, the predetermined target always remains in the field of view of the aircraft's infrared detector, and the flight computer monitors the predetermined target in real time to complete the aircraft's navigation mission.

[0072] On the other hand, the present invention also provides a flight control system based on multi-information collaborative control, comprising the following modules:

[0073] Signal acquisition module: The flight computer obtains the aircraft's GNSS position, aircraft's IMU position, aircraft's infrared detector signal and predetermined target position, initializes the aircraft's ideal trajectory, and obtains the aircraft's ideal position;

[0074] Signal failure detection module: Initialize the failure detection factor threshold, calculate the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculate the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, compare the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, and determine the actual position of the aircraft based on the failure detection results of the GNSS signal and the IMU signal;

[0075] Deviation correction module: initialize the distance threshold, calculate the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initialize the position deviation threshold, calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculate the deviation time interval and the adaptive optimization time, and obtain the aircraft correction acceleration, otherwise continue to monitor the signal parameters, when the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, run the predetermined target tracking module;

[0076] Predetermined target tracking module: The predetermined target is screened through the temperature of each pixel point on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the corresponding pixel points of each suspicious target are calculated to determine the predetermined target, lock and track the predetermined target, and complete the aircraft navigation.

[0077] The beneficial effects brought about by the technical solution provided by the present invention include at least:

[0078] 1. The present invention adopts a flight control method based on multi-information collaborative control. According to the distance between the actual position of the aircraft and the predetermined target position, it determines which sensor information needs to be processed. For example, when the distance is far, the aircraft infrared detector signal is ignored, otherwise it will cause a waste of computing power. Compared with the traditional method of processing a single sensor data or processing all sensor data, the present invention can more accurately guide the aircraft to fly along the optimal flight path while taking into account the computing efficiency, which can reduce the weight of the aircraft itself and the hardware cost, and has obvious economic value;

[0079] 2. Before processing the aircraft GNSS position and the aircraft IMU position, the present invention first performs failure detection on the GNSS signal and the IMU signal to avoid the failure of the flight mission due to sensor errors. Compared with the solution of directly processing the sensor data, the present invention has higher fault tolerance and higher intelligence when facing sensor failures;

[0080] 3. When processing the GNSS position and IMU position of the aircraft, if it is found that there is an obvious deviation between the actual position of the aircraft and the ideal position of the aircraft, the present invention first determines the deviation time interval. When the deviation changes slowly, the correction is accelerated to improve the efficiency of deviation correction. When the deviation changes rapidly, the correction is slowed down to reduce the impact of extreme changes on the flight stability of the aircraft. By using adaptive optimization time to calculate the correction acceleration, the deviation can be eliminated in time. Compared with traditional methods, the present invention can perform adaptive repair for different deviation conditions, reduce the risk of navigation failure, and has higher safety.

[0081] 4. When the distance between the actual position of the aircraft and the predetermined target position is close, the present invention uses the aircraft infrared detector to lock and track the predetermined target. However, the predetermined target usually interferes with the aircraft by immediately releasing or pre-setting other interference targets. The present invention can timely identify the predetermined target by calculating the temperature confidence and grayscale confidence, and eliminate the influence of the interference target on the aircraft identification function. Compared with traditional solutions, the present invention has higher accuracy in locking and tracking targets and can adapt to modern complex application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0083] Figure 1 A flowchart of a flight control method based on multi-information collaborative control provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0084] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0085] Embodiment 1:

[0086] This embodiment will provide a more detailed description of a flight control method based on multi-information cooperative control provided by the present invention in conjunction with the corresponding drawings. Figure 1Specifically, the flight control method of this embodiment includes the following steps:

[0087] Step S1, the flight computer obtains the aircraft GNSS position, the aircraft IMU position, the aircraft infrared detector signal and the predetermined target position, initializes the aircraft ideal trajectory, and obtains the aircraft ideal position; including:

[0088] The flight computer obtains the aircraft's GNSS position ,in

[0089] , The x-axis coordinate of the aircraft's GNSS position. The y-axis coordinate of the aircraft's GNSS position. The z-axis coordinate representing the aircraft's GNSS position;

[0090] The flight computer obtains the aircraft IMU position ,in , Indicates the x-axis coordinate of the aircraft IMU position, Indicates the y-axis coordinate of the aircraft IMU position, Indicates the z-axis coordinate of the aircraft IMU position;

[0091] The flight computer acquires the aircraft's infrared detector signal;

[0092] The flight computer acquires the predetermined target position ,in , represents the x-axis coordinate of the intended target position, represents the y-axis coordinate of the intended target position, The z-axis coordinate representing the predetermined target position;

[0093] Initialize the ideal trajectory of the aircraft and obtain the ideal position of the aircraft ,in , The x-axis coordinate representing the ideal position of the aircraft, The y-axis coordinate representing the ideal position of the aircraft, The z-axis coordinate representing the ideal position of the aircraft.

[0094] Step S2, initializing the failure detection factor threshold, calculating the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculating the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, comparing the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, respectively, and determining the actual position of the aircraft according to the failure detection results of the GNSS signal and the IMU signal; including:

[0095] Initialize the failure detection factor threshold , S represents failure detection;

[0096] Calculate the GNSS failure detection factor based on the aircraft GNSS position and the aircraft ideal position , GNSS failure detection factor at the i-th moment The expression is as follows:

[0097] ;

[0098] in, represents the x-axis coordinate of the aircraft GNSS position at the i-th moment, represents the y-axis coordinate of the aircraft GNSS position at the i-th moment, represents the z-axis coordinate of the aircraft GNSS position at the i-th moment, represents the x-axis coordinate of the ideal position of the aircraft at the i-th moment, represents the y-axis coordinate of the ideal position of the aircraft at the i-th moment, The z-axis coordinate of the ideal position of the aircraft at the i-th moment;

[0099] Calculate the IMU failure detection factor based on the aircraft IMU position and the aircraft ideal position , IMU failure detection factor at the i-th moment The expression is as follows:

[0100] ;

[0101] in, represents the x-axis coordinate of the aircraft IMU position at the i-th moment, represents the y-axis coordinate of the aircraft IMU position at the i-th moment, Represents the z-axis coordinate of the aircraft IMU position at the i-th moment;

[0102] when , it means that the aircraft GNSS position and aircraft IMU position at the i-th moment are both valid. At this time, the actual position of the aircraft at the i-th moment is the GNSS position of the aircraft at the i-th moment;

[0103] when , it means that the GNSS position of the aircraft at the i-th moment is valid but the IMU position of the aircraft is invalid. The IMU position of the aircraft is corrected. At this time, the actual position of the aircraft at the i-th moment is is the GNSS position of the aircraft at the i-th moment;

[0104] when , it means that the GNSS position of the aircraft at the i-th moment is invalid but the IMU position of the aircraft is valid. At this time, the actual position of the aircraft at the i-th moment is is the IMU position of the aircraft at the i-th moment;

[0105] when When the GNSS position and IMU position of the aircraft at the i-th moment are both invalid, the flight computer sends an alarm message to the aircraft command center for manual intervention, and uses the velocity and acceleration information of the previous moment to calculate the actual position of the aircraft at the i-th moment. .

[0106] It should be noted that in actual application scenarios, sensor signals will be affected by many factors. The present invention can realize effective monitoring of aircraft pre-navigation signals by constructing failure detection factors. Once the sensor signal is inaccurate, it can be reported to the command center in time to improve the accuracy of the aircraft's flight process and landing position.

[0107] Step S3, initializing the distance threshold, calculating the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initializing the position deviation threshold, calculating the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculating the deviation time interval and the adaptive optimization time, and obtaining the aircraft correction acceleration, otherwise continue to monitor the signal parameters; including:

[0108] Initialize distance threshold ;

[0109] Calculate the distance between the actual position of the aircraft and the predetermined target position , where the distance between the actual position of the aircraft and the predetermined target position at the i-th moment is The expression is as follows:

[0110] ;

[0111] in, represents the x-axis coordinate of the actual position of the aircraft at the i-th moment, represents the y-axis coordinate of the actual position of the aircraft at the i-th moment, represents the z-axis coordinate of the actual position of the aircraft at the i-th moment, represents the x-axis coordinate of the target position at the i-th moment, represents the y-axis coordinate of the target position at the i-th moment, represents the z-axis coordinate of the target position at the i-th moment;

[0112] when When the flight computer processes only GNSS and IMU signals, it does not process the aircraft's infrared detector signals;

[0113] Initialize position deviation threshold ;

[0114] Calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft , where the deviation between the actual position of the aircraft and the ideal position of the aircraft at the i-th moment is The expression is as follows:

[0115] ;

[0116] when The flight computer continues to monitor GNSS and IMU signals;

[0117] when When , the deviation time interval and adaptive optimization time are calculated to obtain the aircraft correction acceleration; the specific process is as follows:

[0118] Traverse the historical moments before the i-th moment in turn and calculate the deviation of each historical moment , if at the jth moment Greater than 0.1 , then the deviation time interval can be obtained ;

[0119] Calculate the number of positions in the deviation time interval ,in ;

[0120] Initialization time deviation threshold , the expression of adaptive optimization time T is as follows:

[0121] when When ;

[0122] when When ;

[0123] The flight computer obtains the relationship between the x-axis position deviation, y-axis position deviation and z-axis position deviation at the i-th moment and the x-axis direction correction acceleration, y-axis direction correction acceleration and z-axis direction correction acceleration respectively, where the relationship between the i-th moment and the The expression of the above relationship at this moment is as follows:

[0124] ;

[0125] in, Indicates the corrected acceleration in the x-axis direction, Indicates the corrected acceleration in the y-axis direction, Indicates the corrected acceleration in the z-axis direction, represents the ideal speed of the aircraft on the x-axis at the i-th moment, represents the actual speed of the aircraft on the x-axis at the i-th moment, represents the ideal speed of the aircraft on the y-axis at the i-th moment, represents the actual speed of the aircraft on the y-axis at the i-th moment, represents the ideal speed of the aircraft on the z-axis at the i-th moment, represents the actual speed of the aircraft on the z-axis at the i-th moment;

[0126] Obtained by the following formula and :

[0127] ;

[0128] In the Time to At the moment, the corrected acceleration in the x-axis direction is , the corrected acceleration in the y-axis direction is , the corrected acceleration in the z-axis direction is .

[0129] It should be noted that in actual application, the aircraft will adjust the direction of the corrective acceleration as described above during the entire process of eliminating the deviation. The purpose of this is to not only eliminate the deviation in time within the adaptive optimization time, but also eliminate the speed in the direction of the deviation to avoid the immediate occurrence of the deviation again, thereby improving the calculation efficiency of the entire solution.

[0130] Step S4: when the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, the predetermined target is screened by the temperature of each pixel point on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the pixel points corresponding to each suspicious target are calculated to determine the predetermined target; including:

[0131] (1) When When the flight computer processes the aircraft infrared detector signal, the aircraft infrared detector signal generates an infrared image. In this embodiment, the infrared image has 640 pixels. 480;

[0132] (2) Initialization temperature threshold , traverse each pixel on the infrared image, count the number of pixels with temperatures higher than the temperature threshold and record them as the number of suspicious pixels;

[0133] (3) If the number of suspicious pixels is 1, the pixel is directly locked as the predetermined target. If the number of suspicious pixels is greater than 1, there are interference points and further screening is required;

[0134] (4) If the number of suspicious pixels is greater than 1, calculate the temperature confidence U of each suspicious pixel, where the temperature confidence of the kth suspicious pixel is , the expression is as follows:

[0135] ;

[0136] in, Represents the temperature value of the kth suspicious pixel, Represents the number of pixels around the kth suspicious pixel, Indicates the maximum temperature of the pixel in the infrared image. Indicates the minimum value of the pixel temperature in the infrared image;

[0137] Calculate the gray confidence H of each suspicious target, where the gray confidence of the kth suspicious pixel is , the expression is as follows:

[0138] ;

[0139] in, represents the gray value of the kth suspicious pixel, Indicates the maximum value of the grayscale of the pixel in the infrared image. Indicates the minimum gray value of the pixel in the infrared image;

[0140] (5) Initialize temperature confidence threshold and gray confidence threshold If the temperature confidence of the suspicious pixel in the current frame of the infrared image is greater than the temperature confidence threshold and the gray confidence is greater than the gray confidence threshold, the flag FLAG of the suspicious pixel is increased by 1, and 5 frames are taken continuously. If the FLAG of the suspicious pixel is 5, the suspicious pixel is determined to be the predetermined target, otherwise it is an interference point. If there are still multiple suspicious pixels with FLAG of 5 at this time, the K-means clustering method is used to cluster the above suspicious pixels. If it is determined that all suspicious pixels are of the same type, it indicates that the volume of the predetermined target is too large and occupies multiple pixels. The pixel at the center of the cluster is taken as the center of the predetermined target and locked and tracked. Otherwise, the number of frames taken is continued to increase for detection until the only suspicious pixel is distinguished. If the predetermined target is not found in the infrared image, frames are continuously taken for detection until the predetermined target is found and locked and tracked.

[0141] Step S5: After the aircraft locks and tracks the predetermined target, the predetermined target always remains in the field of view of the aircraft's infrared detector, and the flight computer monitors the predetermined target in real time to complete the aircraft's navigation mission.

[0142] Embodiment 2:

[0143] This embodiment provides a flight control system based on multi-information coordinated control, which includes the following modules:

[0144] Signal acquisition module: The flight computer obtains the aircraft's GNSS position, aircraft's IMU position, aircraft's infrared detector signal and predetermined target position, initializes the aircraft's ideal trajectory, and obtains the aircraft's ideal position;

[0145] Signal failure detection module: Initialize the failure detection factor threshold, calculate the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculate the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, compare the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, and determine the actual position of the aircraft based on the failure detection results of the GNSS signal and the IMU signal;

[0146] Deviation correction module: initialize the distance threshold, calculate the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initialize the position deviation threshold, calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculate the deviation time interval and the adaptive optimization time, and obtain the aircraft correction acceleration, otherwise continue to monitor the signal parameters, when the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, run the predetermined target tracking module;

[0147] Predetermined target tracking module: The predetermined target is screened through the temperature of each pixel point on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the corresponding pixel points of each suspicious target are calculated to determine the predetermined target, lock and track the predetermined target, and complete the aircraft navigation.

[0148] The flight control system provided in this embodiment is used to implement the flight control method in the above-mentioned embodiment 1, wherein the functions implemented by each functional module in the flight control system correspond one-to-one to each process step in the flight control method; therefore, they will not be repeated here.

[0149] It should be noted that the serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments. And the terms "including", "comprising" or any other variants thereof in this article are intended to cover non-exclusive inclusion, so that a process, device, article or method including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, device, article or method. In the absence of further restrictions, an element defined by the sentence "including a ..." does not exclude the presence of other identical elements in the process, device, article or method including the element.

[0150] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0151] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A flight control method based on multi-information collaborative control, characterized in that: The following steps are involved: S1. The flight computer obtains the aircraft's GNSS position, the aircraft's IMU position, the aircraft's infrared detector signal and the predetermined target position, initializes the aircraft's ideal trajectory, and obtains the aircraft's ideal position; S2. Initialize the failure detection factor threshold, calculate the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculate the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, compare the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, and determine the actual position of the aircraft according to the failure detection results of the GNSS signal and the IMU signal; S3, initialize the distance threshold, calculate the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initialize the position deviation threshold, calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculate the deviation time interval and the adaptive optimization time, and obtain the aircraft correction acceleration, otherwise continue to monitor the signal parameters; S4. When the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, the predetermined target is screened by the temperature of each pixel point on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the pixel points corresponding to each suspicious target are calculated to determine the predetermined target; S5. Lock and track the predetermined target to complete the aircraft navigation.

2. The flight control method based on multi-information coordinated control according to claim 1, characterized in that: The step S1 comprises the following steps: The flight computer obtains the aircraft's GNSS position ,in , The x-axis coordinate of the aircraft's GNSS position. The y-axis coordinate of the aircraft's GNSS position. The z-axis coordinate representing the aircraft's GNSS position; The flight computer obtains the aircraft IMU position ,in , Indicates the x-axis coordinate of the aircraft IMU position, Indicates the y-axis coordinate of the aircraft IMU position, Indicates the z-axis coordinate of the aircraft IMU position; The flight computer acquires the aircraft's infrared detector signal; The flight computer acquires the predetermined target position ,in , represents the x-axis coordinate of the intended target position, represents the y-axis coordinate of the intended target position, The z-axis coordinate representing the predetermined target position; Initialize the ideal trajectory of the aircraft and obtain the ideal position of the aircraft ,in , The x-axis coordinate representing the ideal position of the aircraft, The y-axis coordinate representing the ideal position of the aircraft, The z-axis coordinate representing the ideal position of the aircraft.

3. The flight control method based on multi-information coordinated control according to claim 2, characterized in that: The step S2 comprises the following steps: Initialize the failure detection factor threshold , S represents failure detection; Calculate the GNSS failure detection factor based on the aircraft GNSS position and the aircraft ideal position , GNSS failure detection factor at the i-th moment The expression is as follows: ； in, represents the x-axis coordinate of the aircraft GNSS position at the i-th moment, represents the y-axis coordinate of the aircraft GNSS position at the i-th moment, represents the z-axis coordinate of the aircraft GNSS position at the i-th moment, represents the x-axis coordinate of the ideal position of the aircraft at the i-th moment, represents the y-axis coordinate of the ideal position of the aircraft at the i-th moment, The z-axis coordinate of the ideal position of the aircraft at the i-th moment; Calculate the IMU failure detection factor based on the aircraft IMU position and the aircraft ideal position , IMU failure detection factor at the i-th moment The expression is as follows: ； in, represents the x-axis coordinate of the aircraft IMU position at the i-th moment, represents the y-axis coordinate of the aircraft IMU position at the i-th moment, Represents the z-axis coordinate of the aircraft IMU position at the i-th moment; when and , it means that the aircraft GNSS position and aircraft IMU position at the i-th moment are both valid. At this time, the actual position of the aircraft at the i-th moment is the GNSS position of the aircraft at the i-th moment; when , it means that the GNSS position of the aircraft at the i-th moment is valid but the IMU position of the aircraft is invalid. The IMU position of the aircraft is corrected. At this time, the actual position of the aircraft at the i-th moment is is the GNSS position of the aircraft at the i-th moment; when , it means that the GNSS position of the aircraft at the i-th moment is invalid but the IMU position of the aircraft is valid. At this time, the actual position of the aircraft at the i-th moment is is the IMU position of the aircraft at the i-th moment; when When the GNSS position and IMU position of the aircraft at the i-th moment are both invalid, the flight computer sends an alarm message to the aircraft command center for manual intervention, and uses the velocity and acceleration information of the previous moment to calculate the actual position of the aircraft at the i-th moment. .

4. The flight control method based on multi-information coordinated control according to claim 3, characterized in that: The step S3 comprises the following steps: Initialize distance threshold ; Calculate the distance between the actual position of the aircraft and the predetermined target position , where the distance between the actual position of the aircraft and the predetermined target position at the i-th moment is The expression is as follows: ； in, represents the x-axis coordinate of the actual position of the aircraft at the i-th moment, represents the y-axis coordinate of the actual position of the aircraft at the i-th moment, represents the z-axis coordinate of the actual position of the aircraft at the i-th moment, represents the x-axis coordinate of the target position at the i-th moment, represents the y-axis coordinate of the target position at the i-th moment, represents the z-axis coordinate of the target position at the i-th moment; when When the flight computer processes only GNSS and IMU signals, it does not process the aircraft's infrared detector signals; Initialize position deviation threshold ; Calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft , where the deviation between the actual position of the aircraft and the ideal position of the aircraft at the i-th moment is The expression is as follows: ； when When , calculate the deviation time interval and adaptive optimization time to obtain the corrected acceleration of the aircraft; when The flight computer continues to monitor the GNSS and IMU signals.

5. The flight control method based on multi-information coordinated control according to claim 4, characterized in that: The step S3 calculates the deviation time interval and the adaptive optimization time to obtain the aircraft correction acceleration, including the following steps: Traverse the historical moments before the i-th moment in turn and calculate the deviation of each historical moment , if at the jth moment Greater than 0.1 , then the deviation time interval can be obtained ; Calculate the number of positions in the deviation time interval ,in ; Initialization time deviation threshold , the expression of adaptive optimization time T is as follows: when When ; when When ; The flight computer obtains the relationship between the x-axis position deviation, y-axis position deviation and z-axis position deviation at the i-th moment and the x-axis direction correction acceleration, y-axis direction correction acceleration and z-axis direction correction acceleration respectively, where the relationship between the i-th moment and the The expression of the above relationship at this moment is as follows: ； in, Indicates the corrected acceleration in the x-axis direction, Indicates the corrected acceleration in the y-axis direction, Indicates the corrected acceleration in the z-axis direction, represents the ideal speed of the aircraft on the x-axis at the i-th moment, represents the actual speed of the aircraft on the x-axis at the i-th moment, represents the ideal speed of the aircraft on the y-axis at the i-th moment, represents the actual speed of the aircraft on the y-axis at the i-th moment, represents the ideal speed of the aircraft on the z-axis at the i-th moment, represents the actual speed of the aircraft on the z-axis at the i-th moment; Obtained by the following formula and : ； In the Time to At the moment, the corrected acceleration in the x-axis direction is , the corrected acceleration in the y-axis direction is , the corrected acceleration in the z-axis direction is .

6. The flight control method based on multi-information coordinated control according to claim 4, characterized in that: The step S4 comprises the following steps: (1) When When the aircraft is in the air, the flight computer processes the aircraft's infrared detector signal and generates an infrared image from the aircraft's infrared detector signal; (2) Initialization temperature threshold , traverse each pixel on the infrared image, count the number of pixels with temperatures higher than the temperature threshold and record them as the number of suspicious pixels; (3) If the number of suspicious pixels is 1, the pixel is directly locked as the predetermined target. If the number of suspicious pixels is greater than 1, there are interference points and further screening is required; (4) If the number of suspicious pixels is greater than 1, calculate the temperature confidence U of each suspicious pixel, where the temperature confidence of the kth suspicious pixel is , the expression is as follows: ； in, Represents the temperature value of the kth suspicious pixel, Represents the number of pixels around the kth suspicious pixel, Indicates the maximum temperature of the pixel in the infrared image. Indicates the minimum value of the pixel temperature in the infrared image; Calculate the gray confidence H of each suspicious target, where the gray confidence of the kth suspicious pixel is , the expression is as follows: ； in, represents the gray value of the kth suspicious pixel, Indicates the maximum value of the grayscale of the pixel in the infrared image. Indicates the minimum gray value of the pixel in the infrared image; (5) Initialize temperature confidence threshold and gray confidence threshold If the temperature confidence of the suspicious pixel in the current frame of the infrared image is greater than the temperature confidence threshold and the gray confidence is greater than the gray confidence threshold, the flag FLAG of the suspicious pixel is increased by 1, and 5 frames are taken continuously. If the FLAG of the suspicious pixel is 5, the suspicious pixel is determined to be the predetermined target, otherwise it is an interference point. If there are still multiple suspicious pixels with FLAG of 5 at this time, the K-means clustering method is used to cluster the above suspicious pixels. If it is determined that all suspicious pixels are of the same type, it indicates that the volume of the predetermined target is too large and occupies multiple pixels. The pixel at the center of the cluster is taken as the center of the predetermined target and locked and tracked. Otherwise, the number of frames taken is continued to increase for detection until the only suspicious pixel is distinguished. If the predetermined target is not found in the infrared image, frames are continuously taken for detection until the predetermined target is found and locked and tracked.

7. A flight control system based on multi-information collaborative control, characterized in that: Includes the following modules: Signal acquisition module: The flight computer obtains the aircraft's GNSS position, aircraft's IMU position, aircraft's infrared detector signal and predetermined target position, initializes the aircraft's ideal trajectory, and obtains the aircraft's ideal position; Signal failure detection module: Initialize the failure detection factor threshold, calculate the GNSS failure detection factor according to the aircraft GNSS position and the ideal position of the aircraft, calculate the IMU failure detection factor according to the aircraft IMU position and the ideal position of the aircraft, compare the failure detection factor threshold with the GNSS failure detection factor and the IMU failure detection factor, and determine the actual position of the aircraft based on the failure detection results of the GNSS signal and the IMU signal; Deviation correction module: initialize the distance threshold, calculate the distance between the actual position of the aircraft and the predetermined target position, when the distance between the actual position of the aircraft and the predetermined target position is greater than the distance threshold, initialize the position deviation threshold, calculate the deviation between the actual position of the aircraft and the ideal position of the aircraft, when the deviation between the actual position of the aircraft and the ideal position of the aircraft is greater than the position deviation threshold, calculate the deviation time interval and the adaptive optimization time, and obtain the aircraft correction acceleration, otherwise continue to monitor the signal parameters, when the distance between the actual position of the aircraft and the predetermined target position is less than or equal to the distance threshold, run the predetermined target tracking module; Predetermined target tracking module: The predetermined target is screened by the temperature of each pixel on the infrared image. If there are multiple suspicious targets, the temperature confidence and grayscale confidence of the corresponding pixel of each suspicious target are calculated to determine the predetermined target, lock and track the predetermined target, and complete the aircraft navigation; To realize the flight control method based on multi-information collaborative control as described in any one of claims 1-6.

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