Synthetic vision correction method and system based on head-up display

Abstract

The invention belongs to the technical field of aircraft navigation and positioning, and particularly relates to a synthetic vision correction method and system based on a head-up display. The method comprises the following steps: acquiring an airport environment image from an airborne visual sensor according to a scene operation stage of an aircraft; identifying airport ground mark features from the image, and matching the airport ground mark features with elements in an airport ground feature database; calculating the current geographic position information of the aircraft through the matched element geographic position information and the relative position information of the element and the current position of the aircraft; correcting errors of the airborne positioning equipment by using the geographic position information; and after correction, transmitting the corrected data to an airborne synthetic visual system, acquiring aircraft attitude data from an airborne sensor, and generating an airport synthetic visual image of the view angle of an aircraft operator at the same angle with an outdoor airport road. According to the invention, the display precision of the synthetic view based on the head-up display can be improved, and the usability of the synthetic view based on the head-up display in the airplane scene operation stage is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft navigation and positioning, and in particular relates to a synthetic vision correction method and system based on a head-up display. Background Art

[0002] The head-up display (HUD) is an important part of the airborne display system. Through various sensor information, after processing and calculation, the HUD displays flight guidance symbols and synthetic vision images. These symbols and images are projected onto the transparent combination mirror directly in front of the pilot and focused at infinity. Guidance symbols and synthetic vision images are equiangular relative to the external vision, and can provide pilots with the most intuitive flight guidance information that cannot be achieved by any other display device.

[0003] At present, when civil aircraft display synthetic vision in the surface operation stage, the source of the aircraft positioning data used is mainly the airborne GNSS (Global Navigation Satellite System) equipment, and the positioning accuracy of general aircraft GNSS equipment is 5 to 10 meters. When the aircraft is in the surface operation stage, the meter-level positioning deviation will cause the airport runway line, taxiway line, etc. in the synthetic vision on the head-up display to deviate too much from the external scene, and the pilot cannot provide equiangular airport runway line, taxiway line, etc. indication when observing the synthetic vision. The synthetic vision display error caused by the positioning error reduces the usability of the airborne synthetic vision based on the head-up display in the surface stage. At present, GBAS (Ground Based Augmentation Systems) is being introduced in China to improve the positioning accuracy, and the positioning accuracy can reach the sub-meter level. However, only a very small number of airports in China have built GBAS. Considering the needs of most domestic airports without GBAS to display synthetic vision for surface guidance through head-up displays during the surface operation stage, it is necessary to further study the correction method and system of airborne synthetic vision based on the head-up display. Summary of the invention

[0004] In view of this, the present invention provides a synthetic vision correction method and system based on a head-up display. When an aircraft is in a scene operation stage, an airborne visual sensor is used to obtain an airport environment image around the aircraft, and the airport ground marking features in the image are extracted and mapped to corresponding elements in an airport ground feature database. The geographical location information of the element in the database and the relative position information in the image are used to calculate the geographical location information of the current position of the aircraft, and the aircraft positioning error is corrected using the information. Then, the position information is transmitted to an airborne synthetic vision system to draw an equiangular scene guidance synthetic vision image displayed on the head-up display, thereby improving the accuracy of the synthetic vision scene guidance on the head-up display during the scene operation stage and enhancing the situation awareness capability of the pilot during the scene operation stage.

[0005] The technical solution of the present invention is:

[0006] A method for correcting synthetic vision based on a head-up display comprises the following steps:

[0007] Step 1, determine whether the aircraft is currently in the field operation stage;

[0008] Step 2, when the aircraft is in the surface operation phase, obtaining an airport environment image around the aircraft from an onboard visual sensor;

[0009] Step 3, performing image processing on the acquired airport environment image to identify the airport ground marking features;

[0010] Step 4: according to the current position of the aircraft output by the airborne positioning device, the area for feature matching is searched from the airport ground mark feature database;

[0011] Step 5, matching the elements of the area in the airport ground marking feature database with the airport ground marking features in the airport environment image, and finding the database elements corresponding to the airport ground marking features in the database;

[0012] Step 6, calculating the relative position information of the aircraft relative to the airport ground marking features through the airport ground marking feature information in the airport environment image;

[0013] Step 7, calculating the current geographical location information of the aircraft through the geographical location information of the corresponding elements of the airport ground features and the relative position information between the geographical location information and the current location of the aircraft;

[0014] Step 8, comparing the calculated current geographical location information of the aircraft with the geographical location information of the aircraft output by the airborne positioning device to determine whether the aircraft positioning is accurate and obtain the aircraft positioning error;

[0015] Step 9, when the positioning error is within the allowable range, correct the aircraft positioning error using the calculated current geographical location information of the aircraft;

[0016] When the positioning error exceeds the allowable range, a positioning error alarm is generated;

[0017] Step 10: Transmit the corrected aircraft positioning information to the airborne synthetic vision system, obtain aircraft attitude data from the airborne sensor, generate an airport synthetic vision image from the aircraft operator's perspective that is equiangular with the exterior airport road, and display the synthetic vision image on the head-up display.

[0018] Furthermore, in step 2, the airport environment image is acquired based on one or more airborne visual sensors, and the airport environment image is an image of the airport in front of or to the side of the aircraft.

[0019] Furthermore, the visual sensor is a sensor in the visible light band and / or a sensor in the infrared band.

[0020] Furthermore, it is identified that the airport ground marking features contain at least 3 feature points.

[0021] Furthermore, an area for feature matching is searched from the airport ground feature database and determined based on the positioning information output by the airborne positioning device and the maximum positioning error of the positioning device.

[0022] Furthermore, the relative position information of the aircraft relative to the airport ground marking features is based on the relative position of the airport ground marking features in the airport environment image, the installation position and angle information of the visual sensor relative to the aircraft reference point, and the visual sensor imaging parameter solution. The relative position information includes distance and direction.

[0023] Furthermore, the synthetic vision image is drawn based on reading the airport map database, taking the current position of the aircraft as the base point, and according to the aircraft attitude and altitude information; the drawing elements at least include images of the sidelines and centerlines of the road in front of the aircraft, and the name of the road where the aircraft is currently located, the name of the target road, and turn instructions are displayed in a prominent position of the synthetic vision image.

[0024] Furthermore, the synthetic vision image also includes flight parameter symbols of ground speed, attitude and altitude generated according to the parameters of the aircraft, and the flight parameter symbols are superimposed and displayed on the synthetic vision image.

[0025] The present invention also proposes a head-up display-based synthetic vision correction system for implementing the head-up display-based synthetic vision correction method, comprising:

[0026] The data interface module is connected to the visual sensor, the airborne positioning device and the airport data link to obtain the aircraft's current flight phase information, positioning data and airport environment images;

[0027] Data storage module, used to store airport ground feature database, airport map database, visual sensor installation and imaging parameters and system logs;

[0028] The vision correction module is connected to the data interface module and is used to process the airport environment images collected by one or more visual sensors, identify the airport ground marking features, and read the airport ground feature database to find the area for feature matching, match the elements of the area in the database with the airport ground marking features in the image, find the corresponding database element, and calculate the geographical location information of the current position of the aircraft through the geographical location information of the element and its relative position information with the current position of the aircraft, so as to correct the aircraft positioning error;

[0029] The graphics processing module is connected to the visual correction module, and is used to receive the corrected aircraft positioning data, read the airport map database, generate the airport synthetic visual image, draw the road sidelines and centerlines that are equiangular with the exterior scene, and draw the name of the road where the aircraft is currently located, the name of the target road, and the turn instructions;

[0030] The head-up display module is connected to the graphics processing module and serves as a carrier for displaying the synthetic vision image directly in front of the aircraft operator.

[0031] Furthermore, the visual correction module is also used to output positioning error warning information when the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device exceeds the allowable range;

[0032] The graphics processing module is also used to receive the positioning error warning information output by the vision correction module, and draw an error warning symbol at a prominent position of the synthetic vision image to remind the aircraft operator that the current aircraft positioning is wrong;

[0033] The graphics processing module is also used to receive aircraft parameters, generate ground speed, attitude and altitude flight parameter symbols, and overlay and draw them on the synthetic vision image.

[0034] Beneficial effects of the present invention:

[0035] 1) At present, the aircraft positioning accuracy of most airports does not meet the requirements of the equiangular display of the synthetic vision on the head-up display for scene guidance. This paper has made a breakthrough in the method of improving the aircraft positioning accuracy during the scene operation phase, improved the display accuracy of the synthetic vision based on the head-up display, and increased the availability of the synthetic vision based on the head-up display during the aircraft scene operation phase;

[0036] 2) The method and system of the present application are compatible with current airport facilities and airborne equipment, and can utilize the existing airborne enhanced vision system to carry out airport environment image acquisition, without increasing the cost of aircraft modification and without adding additional airport facilities, and are applicable to most domestic airports;

[0037] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 This is an architecture diagram of a synthetic vision correction system based on a head-up display according to an embodiment of the present application.

[0040] Figure 2 Schematic diagram of airport ground marking feature recognition in an airport environment image according to an embodiment of the present application.

[0041] Figure 3 This is a correspondence diagram between the airport ground marking features in the airport environment image of an embodiment of the present application and the elements in the airport ground feature database. DETAILED DESCRIPTION

[0042] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0043] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0044] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0045] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The illustrations only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0046] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0047] A synthetic vision correction method based on a head-up display of this embodiment includes the following steps:

[0048] Step 1, determine whether the aircraft is currently in the field operation stage;

[0049] Step 2, when the aircraft is in the surface operation phase, obtaining an airport environment image around the aircraft from an onboard visual sensor;

[0050] Step 3: Process the acquired airport environment image to identify the airport ground marking features, such as Figure 2 As shown;

[0051] Step 4: According to the current position of the aircraft output by the airborne positioning device, the area for feature matching is searched from the airport ground feature database, such as Figure 3 As shown in S3;

[0052] Step 5, match the elements of the area in the airport ground feature database with the airport ground marking features in the airport environment image, and find the database elements corresponding to the airport ground marking features in the database. The corresponding relationship is as follows: Figure 3 As shown in A1;

[0053] Step 6, calculating the relative position information of the aircraft relative to the airport ground marking features through the airport ground marking feature information in the airport environment image;

[0054] Step 7, calculating the geographical location information of the current position of the aircraft through the geographical location information of the corresponding elements of the airport ground features and the relative position information between the geographical location information and the current position of the aircraft;

[0055] Step 8, using the calculated current geographical location information of the aircraft to compare with the geographical location information of the aircraft output by the airborne positioning device to determine whether the aircraft positioning is accurate;

[0056] Step 9: If the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device is within an allowable range, the calculated current geographical location information of the aircraft is used to correct the aircraft positioning error;

[0057] If the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device exceeds the allowable range, an aircraft positioning error alarm will be displayed on the head-up display;

[0058] Step 10: Transmit the corrected aircraft positioning information to the airborne synthetic vision system, obtain aircraft attitude data from the airborne sensor, generate an airport synthetic vision image from the aircraft operator's perspective that is equiangular with the exterior airport road, and display the synthetic vision image on the head-up display.

[0059] In this embodiment, the determination of whether the aircraft is currently in the field operation phase uses airborne inertial navigation and atmospheric aircraft sensor data, wheel-borne signals, and airport air traffic control (ATC) data to comprehensively determine the aircraft's current flight phase.

[0060] In this embodiment, the airport environment image around the aircraft is obtained from the airborne visual sensor, and one or more visual sensors may be used to obtain the airport environment image in front of or to the side of the aircraft.

[0061] In this embodiment, the visual sensor may use a sensor in the visible light band or a sensor in the infrared band.

[0062] In this embodiment, the identified airport ground marking features include at least three feature points.

[0063] In this embodiment, the area for feature matching is searched from the airport ground feature database and is determined based on the longitude and latitude information output by the airborne positioning device and the maximum positioning error of the device.

[0064] In this embodiment, the calculation of the relative position information of the aircraft relative to the airport ground marking features requires the use of information such as the relative position of the airport ground marking features in the airport environment image, the installation position and angle information of the visual sensor relative to the aircraft reference point, and the imaging parameters of the visual sensor. The calculated relative position information includes information such as distance and direction.

[0065] In this embodiment, the synthetic visual image is displayed on a head-up display, and the airport map database is read. Taking the current position of the aircraft as the base point, at least information such as the sideline and center line of the road in front of the aircraft is drawn according to the aircraft's attitude and altitude information, and the name of the road where the aircraft is currently located, the name of the target road, and turn instructions are displayed in a prominent position on the image.

[0066] In this embodiment, when the head-up display displays the synthetic vision image, flight parameter symbols such as ground speed, attitude, altitude, etc. are also generated according to the parameters of the aircraft and superimposed and displayed on the synthetic vision image.

[0067] In one embodiment, the present invention further proposes a synthetic vision correction system for implementing the synthetic vision correction method based on a head-up display of the above embodiment, comprising:

[0068] The data interface module is connected to the visual sensor, the airborne positioning device and the airport data link to obtain the aircraft's current flight phase, positioning data and airport environment images;

[0069] Data storage module, used to store airport ground feature database, airport map database, visual sensor installation and imaging parameters and system logs;

[0070] The vision correction module is connected to the data interface module and is used to process the airport environment images collected by one or more visual sensors, identify the airport ground marking features, and read the airport ground feature database to find the area for feature matching, match the elements of the area in the database with the airport ground marking features in the image, find the corresponding database element, and calculate the geographical location information of the current position of the aircraft through the geographical location information of the element and its relative position information with the current position of the aircraft, so as to correct the aircraft positioning error;

[0071] The graphics processing module is connected to the visual correction module, and is used to receive the corrected aircraft positioning data, read the airport map database, generate the airport synthetic visual image, draw the road sidelines and centerlines that are equiangular with the exterior scene, and draw the name of the road where the aircraft is currently located, the name of the target road, and the turning instructions;

[0072] The head-up display module is connected to the graphics processing module and serves as a carrier for displaying the synthetic vision image directly in front of the aircraft operator.

[0073] In this embodiment, the vision correction module is further configured to output positioning error warning information when the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device exceeds an allowable range.

[0074] In this embodiment, the graphics processing module is further used to receive positioning error warning information output by the vision correction module, and draw an error warning symbol at a prominent position of the synthetic vision image to prompt the aircraft operator that the current aircraft positioning is wrong.

[0075] In this embodiment, the graphics processing module is also used to receive aircraft parameters, generate flight parameter symbols such as ground speed, attitude, altitude, etc., and overlay and draw them on the synthetic visual image.

[0076] In one embodiment, the present invention further provides a synthetic vision correction system based on a head-up display, which is installed inside an aircraft, such as Figure 1 As shown, it includes a data interface module, a vision correction module, a graphics processing module, a data storage module, a head-up display module, etc.

[0077] Specifically, the data interface module is connected to the aircraft's inertial navigation, ground speed, radio altitude, and atmospheric aircraft sensors, and receives aircraft positioning data through a GNSS positioning device, and receives images of the airport environment around the aircraft through an enhanced vision system. The vision correction module is connected to the data interface module, the data storage module, and the graphics processing module, and the graphics processing module is connected to the data storage module and the aircraft cockpit head-up display module.

[0078] The aircraft acquires images of the surrounding airports through the enhanced vision system, and then the synthetic vision correction system based on the head-up display in this example performs feature recognition and matching, completes the aircraft positioning correction, and generates and displays the synthetic vision scene guidance image based on the head-up display:

[0079] The data interface module receives avionics data from sensors such as inertial navigation, radio altimeter, GNSS, and atmospheric machine, determines whether the aircraft is in the field operation phase, and transmits aircraft parameters to the vision correction module and the graphics processing module. It also receives the airport environment image output by the enhanced vision system and transmits it to the vision correction module for correction of the synthetic vision.

[0080] When the aircraft is in the surface operation phase, the vision correction module receives the airport environment image output by the enhanced vision system, identifies the airport ground features in the image, and reads the airport ground feature database to find the area for feature matching, matches the elements of the area in the database with the airport ground marking features in the image, finds the corresponding database element, and calculates the geographical location information of the aircraft's current position through the geographical location information of the element and its relative position information with the aircraft's current position;

[0081] When the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device is within the allowable range, the calculated current geographical location information of the aircraft is used to correct the aircraft positioning error;

[0082] When the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device exceeds the allowable range, an aircraft positioning error warning message is output to the graphics processing module;

[0083] The graphics processing module receives the aircraft parameters and the corrected aircraft positioning information, reads the airport map database, and draws a synthetic visual image from the perspective of the aircraft operator at the same angle as the external airport road based on the aircraft's current longitude, latitude, altitude, and the three-dimensional digital model of the earth, including the road sidelines and centerlines, and draws the name of the road the aircraft is currently on, the name of the target road, and turn instructions;

[0084] The head-up display module receives synthetic vision images and displays them directly in front of the aircraft operator.

[0085] Specifically, when generating a synthetic vision image, the graphics processing module will also generate flight parameter symbols such as ground speed, attitude, altitude, etc. according to the aircraft parameters, and overlay them on the synthetic vision image.

[0086] Specifically, after receiving the aircraft positioning error warning information output by the vision correction module, the graphic processing module draws an error warning symbol at a prominent position of the synthetic vision image to prompt the aircraft operator that the current aircraft positioning is wrong.

[0087] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A synthetic vision correction method based on a head-up display, characterized in that: The following steps are involved: Step 1, determine whether the aircraft is currently in the field operation stage; Step 2, when the aircraft is in the surface operation phase, obtaining an airport environment image around the aircraft from an onboard visual sensor; Step 3, performing image processing on the acquired airport environment image to identify the airport ground marking features; Step 4: according to the current position of the aircraft output by the airborne positioning device, the area for feature matching is searched from the airport ground mark feature database; Step 5, matching the elements of the area in the airport ground marking feature database with the airport ground marking features in the airport environment image, and finding the database elements corresponding to the airport ground marking features in the database; Step 6, calculating the relative position information of the aircraft relative to the airport ground marking features through the airport ground marking feature information in the airport environment image; Step 7, calculating the current geographical location information of the aircraft through the geographical location information of the corresponding elements of the airport ground features and the relative position information between the geographical location information and the current location of the aircraft; Step 8, comparing the calculated current geographical location information of the aircraft with the geographical location information of the aircraft output by the airborne positioning device to determine whether the aircraft positioning is accurate and obtain the aircraft positioning error; Step 9, when the positioning error is within the allowable range, correct the aircraft positioning error using the calculated current geographical location information of the aircraft; When the positioning error exceeds the allowable range, a positioning error alarm is generated; Step 10: Transmit the corrected aircraft positioning information to the airborne synthetic vision system, obtain aircraft attitude data from the airborne sensor, generate an airport synthetic vision image from the aircraft operator's perspective that is equiangular with the exterior airport road, and display the synthetic vision image on the head-up display.

2. The synthetic vision correction method according to claim 1, characterized in that: In step 2, the airport environment image is acquired based on one or more airborne visual sensors, and the airport environment image is an image of the airport in front of or to the side of the aircraft.

3. The synthetic vision correction method according to claim 2, characterized in that: The visual sensor is a sensor in the visible light band and / or a sensor in the infrared band.

4. The synthetic vision correction method according to claim 1, characterized in that: The airport ground marking features are identified to contain at least 3 feature points.

5. The synthetic vision correction method according to claim 1, characterized in that: The area used for feature matching is searched from the airport ground feature database and is determined based on the positioning information output by the onboard positioning device and the maximum positioning error of the positioning device.

6. The synthetic vision correction method according to claim 1, characterized in that: The relative position information of the aircraft relative to the airport ground marking features is based on the relative position of the airport ground marking features in the airport environment image, the installation position and angle information of the visual sensor relative to the aircraft reference point, and the imaging parameter solution of the visual sensor. The relative position information includes distance and direction.

7. The synthetic vision correction method according to claim 1, characterized in that: The synthetic vision image is drawn based on reading the airport map database, taking the current position of the aircraft as the base point, and according to the aircraft attitude and altitude information; the drawing elements at least include images of the sidelines and centerlines of the road in front of the aircraft, and the name of the road where the aircraft is currently located, the name of the target road, and turn instructions are displayed in a prominent position of the synthetic vision image.

8. The synthetic vision correction method according to claim 7, characterized in that: The synthetic vision image also includes flight parameter symbols of ground speed, attitude and altitude generated according to the parameters of the aircraft, and the flight parameter symbols are superimposed and displayed on the synthetic vision image.

9. A system for correcting synthetic vision based on a head-up display, which implements the method for correcting synthetic vision based on a head-up display according to any one of claims 1 to 8, characterized in that: include: The data interface module is connected to the visual sensor, the airborne positioning device and the airport data link to obtain the aircraft's current flight phase information, positioning data and airport environment images; Data storage module, used to store airport ground feature database, airport map database, visual sensor installation and imaging parameters and system logs; The vision correction module is connected to the data interface module and is used to process the airport environment images collected by one or more visual sensors, identify the airport ground marking features, and read the airport ground feature database to find the area for feature matching, match the elements of the area in the database with the airport ground marking features in the image, find the corresponding database element, and calculate the geographical location information of the current position of the aircraft through the geographical location information of the element and its relative position information with the current position of the aircraft, so as to correct the aircraft positioning error; The graphics processing module is connected to the visual correction module, and is used to receive the corrected aircraft positioning data, read the airport map database, generate the airport synthetic visual image, draw the road sidelines and centerlines that are equiangular with the exterior scene, and draw the name of the road where the aircraft is currently located, the name of the target road, and the turn instructions; The head-up display module is connected to the graphics processing module and serves as a carrier for displaying the synthetic vision image directly in front of the aircraft operator.

10. The synthetic vision correction system according to claim 9, characterized in that: The visual correction module is also used to output positioning error warning information when the difference between the calculated current geographical location information of the aircraft and the geographical location information of the aircraft output by the airborne positioning device exceeds the allowable range; The graphics processing module is also used to receive the positioning error warning information output by the vision correction module, and draw an error warning symbol at a prominent position of the synthetic vision image to remind the aircraft operator that the current aircraft positioning is wrong; The graphics processing module is also used to receive aircraft parameters, generate ground speed, attitude and altitude flight parameter symbols, and overlay and draw them on the synthetic vision image.

Images