Method for generating ideal track of chart program based on navigation database coding

Abstract

The invention discloses a navigation database coding-based chart program ideal track generation method, which comprises the following steps of: coding a flight program according to a flight path suspension code, converting a corresponding program into a series of flight segments in a navigation database according to a chart and a coding table, and generating a navigation database; a program in a navigation database is called to connect a series of flight segments in series for resolving, so that a complete flight plan is obtained; wherein the flight path suspension code is used for indicating a flight path ending code in a flight program and is used for indicating an action which should be taken after a specific flight segment is completed; the flight path can be obtained through analysis and simulation, and then the flight program is optimized.

Description

Technical Field

[0001] The invention relates to the technical field of navigation database coding, in particular to a method for generating an ideal trajectory of an aeronautical chart program based on navigation database coding. Background Art

[0002] At present, European and American scholars have conducted in-depth research on flight program simulation, especially flight programs in the terminal area. Many foreign scholars have adopted computer simulation methods when conducting terminal area program optimization research. For example, KHARDI S and other researchers have developed a model for optimizing flight programs in many aspects such as noise reduction and reducing fuel operating costs. They constructed a differential equation group for the functional relationship between the limiting factor variables and flight program optimization, and found the optimal approach and departure track points through mapping relationships. Some scholars have also developed simulation models based on flight management systems. For example, Ramasamy et al. constructed a key mathematical model for calculating and generating three-dimensional flight trajectories, and analyzed and studied the uncertainty influencing factors in the actual flight trajectory and the target flight trajectory, providing research ideas for subsequent simulation research on RNP.

[0003] With the rapid development of China's civil aviation industry and the continuous improvement of flight safety requirements, the research on airport terminal flight procedures has gradually received attention. For example, Zhang Yue and Hu Huaqing proposed in 2010 to introduce computer software modeling, simulation and evaluation in the long-term development and planning of airports to analyze the airspace operation status, so as to verify whether the airspace plan can achieve the expected goals. Yang Lei modeled the flight procedures of a certain civil-military airport through AirTop modeling, analyzed and judged the conflict points of the program in advance through simulation, and continuously optimized the program structure. Xu Tao, Chen Xuerui and others studied the representation method of the flight procedure trajectory in the terminal area, proposed a track similarity measurement method based on the area weighting between tracks, and used the CURE algorithm to realize track clustering and established a flight program trajectory representation model. Xiang Heng and other scholars simulated the flight program on the three-dimensional Google earth terrain, and drew the protection area and calculated the obstacle clearance by inputting important information such as the coordinate position of the navigation station, the runway orientation and configuration, to assist in the design of the optimal flight program.

[0004] Nowadays, the simulation research on flight procedures in China is mainly focused on the final approach, and there is relatively little research on approach and departure procedures. Since my country fully promoted the flight procedures based on database coding later than foreign countries, and the confidentiality requirements of NAIP charts have resulted in many scholars being unable to access the flight procedures of domestic airports, there is not much relevant data. However, the simulation research on flight procedures based on database coding still faces challenges such as the need to improve simulation accuracy, the inability to effectively simulate the simultaneous approach of multiple aircraft, and the incomplete simulation model, which require further in-depth research and discussion. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the purpose of the present invention is to provide a method for generating an ideal trajectory of an aeronautical chart program based on navigation database encoding. The present invention can analyze and simulate the flight trajectory and then optimize the flight program.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a method for generating an ideal trajectory of a chart program based on navigation database coding, comprising:

[0007] The flight program is encoded according to the path abort code, and the corresponding program is converted into a series of segments in the navigation database according to the aeronautical chart and the coding table. The program in the navigation database is called to connect the series of segments together for solution, so as to obtain a complete flight plan; among them, the path abort code is used in the flight program to indicate the end of the flight path, and is used to indicate the action to be taken after completing a specific segment.

[0008] As a further improvement of the present invention, in the solution process, the earth's surface is regarded as a plane, the preset route is planned as a straight line or arc on the local tangent plane, and various navigation parameters and guidance instructions are approximately calculated in this rectangular plane.

[0009] As a further improvement of the present invention, when the calculated heading is greater than 360°, 360° is subtracted by default, and when the calculated heading is less than 360°, the result obtained by subtracting the calculated value from 360° is the final result.

[0010] As a further improvement of the present invention, the navigation database is a navigation database standard format ARI NC424 specification established by the Aviation Electronics Industry Association ARINC.

[0011] As a further improvement of the present invention, the flight segments include: CF segment, which means flying along a certain track to a certain navigation station or positioning point; CA segment, which means keeping a certain track to a certain altitude; CI segment, which means keeping the route angle to cut into the next segment; IF segment, which means starting the positioning point; TF segment, which means flying directly from one positioning point to another along the great circle route; DF segment, which means flying directly to a certain positioning point; FA segment, which means keeping the route angle from a certain positioning point to a certain altitude; FM segment, which means keeping the route angle from a certain positioning point to an artificial end point; RF segment, which means turning to a positioning point with a fixed radius; HF segment, which means waiting at a certain positioning point; HA segment, which means waiting at a certain positioning point to climb to another altitude; HM segment, which means waiting at a certain positioning point until artificial termination; VA segment, which means keeping the heading to a certain altitude; VI segment, indicating maintaining the heading until cutting into the next segment; VM segment, indicating maintaining the heading to the artificial end point; FC segment, indicating flying along a certain track to a point at a specified distance from the navigation station or positioning point; FD segment, indicating flying along a certain track to a specified DME distance; PI segment, indicating a procedure turn, used for right-angle procedures; CD segment, indicating flying along a certain track to a specified DME distance and crossing it; CR segment, indicating flying along a certain track to a specified radial line of a VOR navigation station; AF segment, indicating flying along the DME arc from an uncertain positioning point on the DME arc to the next positioning point; VD segment, indicating flying over a point at a specific DME distance at a certain heading starting from the previous waypoint; VR segment, indicating flying to a specific VOR radial line at a certain heading starting from the previous waypoint.

[0012] The beneficial effects of the present invention are:

[0013] The present invention takes the chart program based on database coding as the entry point, simulates the specific flight program based on Matlab software, and can analyze and simulate the flight trajectory to optimize the flight program. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the DF segment in an embodiment of the present invention;

[0015] Figure 2 Schematic diagram of the turning radius of the CF segment being too large or too small in an embodiment of the present invention;

[0016] Figure 3 This is a schematic diagram of the FC segment in an embodiment of the present invention;

[0017] Figure 4 This is a schematic diagram of the FA segment in an embodiment of the present invention;

[0018] Figure 5 Schematic diagram of CA and VA segments in an embodiment of the present invention

[0019] Figure 6 This is a schematic diagram of the FD segment in an embodiment of the present invention;

[0020] Figure 7 Schematic diagram of CD and VD segments in an embodiment of the present invention;

[0021] Figure 8 This is a schematic diagram of a VM segment in an embodiment of the present invention;

[0022] Fig. 9 Schematic diagram of VR and CR segments in an embodiment of the present invention;

[0023] Fig.10 Schematic diagram of a waiting route sector in an embodiment of the present invention;

[0024] Fig.11 This is a schematic diagram of adding a waiting route in parallel in an embodiment of the present invention;

[0025] Fig.12 This is a schematic diagram of adding a waiting route with an offset in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] Example

[0028] A method for generating an ideal trajectory of a chart program based on navigation database coding, comprising:

[0029] 1. Path abort code:

[0030] A path abort code is a code used in a flight procedure to indicate the end of a flight path. It is used to instruct the pilot on the action to take after completing a specific segment. In flight procedure design, the role of a path abort code is crucial, ensuring that the flight path is consistent with the code table, the waypoint flyover / fly-by markings on the chart are consistent with the code table markings, and the navigation performance requirements are consistent with the procedure design. In addition, the path abort codes and their arrangement sequence must comply with the ARINC424 standard to ensure the accuracy and safety of the flight procedure.

[0031] The concept of a path abort code is to encode the flight procedure. According to the chart and the code table, the corresponding procedure is converted into a series of ARI NC424 segments in the navigation database. The program in the navigation database is retrieved and connected in series. It is input into the FMS to obtain a complete flight plan. At present, 23 types of segments converted into computer languages ​​have been created. This set of codes specifies the expected route from takeoff, passing through each departure segment to a point on the route, or from the route through each arrival segment and approach segment to the missed approach point, landing runway end or missed approach holding point. The path abort code is generally composed of two letters, the first letter indicates the type of path flown, and the second letter indicates where the segment ends. For example, a direct route from a certain fixed point to another fixed point can be defined as "TF" with a path abort code, where "T" represents the type of path flown (here refers to a track), and "F" indicates that the segment ends at a fixed point. The path abort code is described in Table 1:

[0032] Table 1 Description of path abort codes

[0033]

[0034]

[0035] 2. Path abort code calculation logic:

[0036] This embodiment mainly introduces the calculation logic of the path stop code when the flight distance is short. At present, for the sake of simplicity, the industry generally regards a small area of ​​the earth's surface as a plane, and the preset route is planned as a straight line or arc on the local tangent plane, and various navigation parameters and guidance instructions are approximately calculated in this rectangular plane; when the flight distance is long, generally exceeding 50km, the spherical model of the earth's surface must be taken into account.

[0037] The azimuth and heading in the following solution logic are true azimuth and true heading. When the calculated heading is greater than 360°, 360° is subtracted by default. When the calculated heading is less than 360°, the result obtained by subtracting the calculated value from 360° is the final result. Since the IF segment is a point and the TF segment is a line connecting two points, the above two segments are relatively simple, so they are not described in detail. In this embodiment, the ARINC424 database for some segments does not require a starting point, but such segments actually start from the end point of the previous segment, so the starting point of such segments is used as a known condition for solution.

[0038] 2.1、DF segment:

[0039] Figure 1 The figure below is a schematic diagram of the DF segment, where point A is the starting point, point B is the end point, and PA is the previous segment. The entire segment is divided into the turning segment AC and the direct flight segment CB, and O is the center of the turning segment.

[0040] Known: the heading of the previous leg (PA) θ0; the latitude and longitude of the starting point A (X A , Y A ); latitude and longitude of stop point B (X B , Y B ); turning radius r (and OA, OB length, in kilometers); turning direction;

[0041] Required solution: latitude and longitude of point C (X C , Y C );

[0042] Solution: First, we can calculate the position θ of O relative to point A. OA =θ0±90° (left turn is minus, right turn is plus). Since the earth can be regarded as a plane within a short distance, the Pythagorean theorem can be used to solve the problem. Substitute the longitude and latitude of point A and the length of AC into the distance formula between two points on the same longitude and latitude, and then substitute the longitude and latitude of point O (X O ,Y O ) is as follows:

[0043]

[0044] The Pythagorean theorem can also be used to obtain the relative position of two points with known longitude and latitude (the longitude and latitude of the two points are (X1, Y1) and (X2, Y2) respectively). The formula is as follows:

[0045]

[0046] The (X O ,Y O ) and the known (X B , X B ) into formula (2) to obtain the relative position θ of point B with respect to point O OB , then we need to find the length of OB. To find the distance D between two points with known longitude and latitude, we can substitute the longitude and latitude of the two points (the longitude and latitude of the two points are (X1, Y1) and (X2, Y2)) into the distance formula between two points on the same longitude and latitude, and then use the Pythagorean theorem to find the distance. The formula is as follows:

[0047]

[0048] The known (X O ,Y O ) and (X B , Y B ) into formula (3) to obtain the OB length D OB , and the orientation of point C relative to point O is θ Oc And for (Left turn is plus, right turn is minus). Oc and (X O ,Y O ) into formula (3.1) to obtain (X C , Y C ). With the longitude and latitude of point A and point C and the turning radius, the turning segment can be constructed. The direct flight segment can be obtained by connecting point C and point B.

[0049] 2.2、CF segment:

[0050] The horizontal diagram of the CF segment is similar to that of the DF segment, except that the known conditions are different. The construction logic of the CF segment will continue to use Figure 1 Provide explanation.

[0051] Known: the heading θ0 of the previous leg (PA); the altitude, longitude and latitude (X A , Y A ); latitude and longitude of stop point B (X B , Y B );CF segment heading (and CB heading)θ;

[0052] Required solution: latitude and longitude of point C (X C , Y C ); turning radius r (and OA, OB length, in kilometers); turning direction;

[0053] Solution: The turning direction can be obtained by comparing θ0 and θ. The formula is:

[0054]

[0055] At this time, all known data can be substituted into the DF segment solution logic for solution. An arbitrary value is first input for the turning radius r. According to the CF segment characteristics and the DF segment solution logic in this article, it can be known that if the input turning radius is too large or too small, the result will not match the CF segment characteristics. Figure 2 As shown, the red line is the track with a turning radius that is too large, and the blue line is the track with a turning radius that is too small.

[0056] observe Figure 2 It can be found that when the turning direction is left, the heading of the blue track direct flight segment is significantly greater than the heading of the CB segment, while the red segment is the opposite (the opposite when the turning direction is right). From this, it can be inferred that the relationship between the magnitude of the direct flight segment heading θ1 and the CF segment heading θ in the DF calculation result and the turning radius r is:

[0057]

[0058] If the turning direction is right, then

[0059] Since the coordinates of the connecting point C between the turning segment and the direct flight segment can be calculated by solving the DF segment, θ1 can be calculated by substituting the longitude and latitude of point C and point B into formula (2):

[0060] The above formula can be used to calculate θ1, and then substitute it into formula (5) to determine whether the obtained r is too large or too small. According to the difference between θ1 and θ, r can be appropriately increased or decreased, and the above steps can be repeated again. After continuous iteration, the CF segment can be obtained.

[0061] 2.3、FC segment:

[0062] Figure 3 This is a schematic diagram of the FC segment, with point A as the starting point and point B as the end point.

[0063] Known: The latitude and longitude of the starting point A (X A , Y A );FC segment heading (and AB heading) θ;segment length (and AB length) D.

[0064] Required solution: Latitude and longitude of stop point B (X B , Y B ).

[0065] Solution: Replace (X A , Y A ), θ, D into formula (1) to obtain the longitude and latitude of B (X B , Y B ), and then connect the two points AB with a straight line to complete the construction of the FC segment.

[0066] FA segment:

[0067] The FA segment starts from a specified waypoint and follows a specified track to a specified altitude. Figure 4 This is a schematic diagram of the FA and CA segments, with point A as the starting point and point B as the end point.

[0068] Known: The latitude and longitude of the starting point A (X A , Y A ), altitude H0; stop point B altitude H (and target altitude); segment heading θ; climb rate ROC (in m / s); flight speed V (in m / s);

[0069] Required solution: The longitude and latitude of the stop point B (X B , Y B );

[0070] Solution: First calculate the length D of segment AB, the formula is as follows

[0071]

[0072] D and θ, (XA , Y A ) into formula (1) to obtain the longitude and latitude of the stop point B (X B , Y B ), connect point A and point B to complete the construction of FA segment and CA segment.

[0073] 2.4、CA and VA sectors:

[0074] The CA segment starts from any given point and follows a specified track until it ends at a specified altitude. The VA segment starts from any given point and follows a specified heading until it ends at a specified altitude. Since the influence of wind will not be considered in this article, the heading and track are consistent. Therefore, the VA segment and the CA segment will be solved using the same method in this embodiment. Figure 5 It is a schematic diagram of the CA and VA segments. Point A in the figure is the end point of the previous segment (and the starting point of this segment), the PA direction is the direction of the previous segment, point B is the end point, and the entire segment is divided into the turning segment AC and the direct flight segment CB, and O is the center of the turning segment.

[0075] Known: the heading of the previous leg (PA) θ0; the longitude and latitude of point A (X A , Y A ), altitude H0; stop point B altitude H (and target altitude); turning radius r (and OA, OB length, in kilometers); CD segment heading θ; climb rate ROC (in m / s); flight speed V (in m / s);

[0076] Required solution: The longitude and latitude of the stop point B (X B , Y B ); latitude and longitude of point C (X C , Y C ); Turn direction;

[0077] Solution: First, the turning direction can be obtained by formula (3). The orientation of O relative to point A is θ AO =θ0±90° (left turn is minus, right turn is plus). AO and the latitude and longitude of point A (X A , Y A ) into formula (1) to obtain the longitude and latitude of point O (X O , Y O ). The orientation of C relative to point O is θ OC is θ AO ±(180°-∠AOC), since the size of ∠AOC is very large compared to the heading change, θ OC =θ AO ±(180°-|θ0-θ|)(left turn is plus, right turn is minus), change θ OC and (X O , Y O) into formula (1) to obtain the longitude and latitude of point C (X C , Y C ).

[0078] Next, we need to find the longitude and latitude of the stop point B (X B , Y B ), first we need to calculate the total length D of the segment, and substitute H, H0, V, and ROC into formula (6) to calculate it. Since the radius and center angle of the AC segment arc are known, the length of the AC segment arc can be calculated. CB length D BC The total length of the extreme segment D minus the length of the arc of segment AC. BC Substituting θ into formula (1) can obtain the longitude and latitude of the stop point B (X B , Y B ). Connect AC with an arc and CB with a straight line to complete the segment construction.

[0079] 2.5、FD segment:

[0080] The FD segment starts from a given fix point and maintains the track angle to fly to the specified DME distance. Figure 6 Point A is the starting point, point B is the ending point, and point M is the designated DME station.

[0081] Known: The latitude and longitude of the starting point A (X A , Y A ); latitude and longitude of point M (and longitude and latitude of designated DME station) (X M , Y M ); AB direction (and specified heading) θ; BM length (and specified DME distance) D; point B height H.

[0082] Required solution: latitude and longitude of point B (X B , Y B );

[0083] First find the horizontal distance between point B and point M as D BM , the formula is Next, enter an AB length D AB0 =0.01 km and substitute it and θ into formula (1) to obtain the longitude and latitude of point B. Then substitute the longitude and latitude of point B and point M into formula (3) to calculate the BM length D at this time. BM0 By comparing D BM0 With D BM The size relationship is in units of 0.01 km in the first input D AB0 Repeat the above steps again until D BM0 With D BM When the difference is within 0.01 km, stop the calculation and output the D in the last calculation AB0 For the final DAB . The output D AB Substituting θ into formula (1) can calculate the longitude and latitude of point B (X B , Y B ). Connect CB with a straight line to complete the segment construction.

[0084] 2.6、CD、VD sectors:

[0085] The CD segment starts from any given point and follows the specified track until the specified DME distance is reached. The VD segment starts from any given point and follows the specified heading until the specified distance is reached. Since the wind effect is not considered in this embodiment, the heading is consistent with the track. Therefore, the VD segment and the CD segment will be solved using the same method in this embodiment. Figure 7 This is a schematic diagram of the CA and VA segments. Point A in the figure is the end point of the previous segment (and the starting point of this segment), the PA direction is the direction of the previous segment, point B is the end point, M is the designated DME station, and the entire segment is divided into the turning segment AC and the direct flight segment CB, and O is the center of the turning segment.

[0086] Known: The latitude and longitude of the starting point A (X A , Y A ); latitude and longitude of point M (and longitude and latitude of designated DME station) (X M , Y M ); AB direction (and specified heading) θ; heading of the previous segment (PA) θ0; turning radius r (and OA, OB length, in kilometers); BM length (and specified DME distance) D; height H of point B.

[0087] Required solution: latitude and longitude of point B (X B , Y B ); latitude and longitude of point C (X C , Y C ).

[0088] Solution method: This segment is divided into two segments for solution, which is the same as the CD and VD segments. First, solve the longitude and latitude of point C. Substitute the known conditions into the solution method of the turning segment in the CD and VD segments to find the longitude and latitude of point C (X C , Y C Then, the longitude and latitude of point C (X C , Y C ) and other known conditions into the FD segment solution to find the longitude and latitude of point B (X B , Y B ). Connect AC with an arc and CB with a straight line to complete the segment construction.

[0089] 2.7、RF、AF segments:

[0090] The RF segment is a fixed radius turning segment, and the AF segment is to fly from a point on the DME arc to a specified point along the DME arc. Since the turns in the calculation of these two path stop codes can be regarded as an arc, and the longitude and latitude of the starting point of the arc (the starting point of the AF segment is the end point of the previous segment), the longitude and latitude of the end point, the longitude and latitude of the center of the circle, and the radius are all known, and the data required for the calculation are the above data, then the two path stop codes do not require data to be solved.

[0091] 2.8、VM, FM segments:

[0092] The FM segment is to maintain the track from a point until it is manually terminated, and the VM segment is to maintain the heading from a point until it is manually terminated. Since the influence of wind will not be considered in the simulation of this paper, the heading is the track, and the FM segment and the VM segment will be constructed in the same way. Figure 8 shown.

[0093] Known: latitude and longitude of point A (X A , Y A ); segment heading θ; termination time (and total flight time) T; flight speed V;

[0094] Required solution: latitude and longitude of point B (X B , Y B );

[0095] Solution: First, we need to get the length D of AB, which can be obtained by multiplying T and V. Then we can calculate the latitude and longitude of point A (X A , Y A ) and D into formula (1) to obtain the longitude and latitude of point B (X B , Y B ). Connect CB with a straight line to complete the segment construction.

[0096] 2.9、VR, CR segments:

[0097] The VR segment is to maintain the track until the specified VOR radial line is terminated, and the CR segment is to maintain the heading until the specified VOR radial line is terminated. Since the influence of wind will not be considered in the simulation of this embodiment, the heading and are the track, and the VR segment and the VR segment will be constructed using the same method. Fig. 9 In the figure, point A is the starting point of the segment, point B is the end point of the segment, AC is the turning segment, CB is the direct flight segment, and V is the designated VOR station.

[0098] Known: latitude and longitude of point A (X A , Y A );Segment heading θ;V point latitude and longitude (X V , Y V );VB direction (and radial line orientation)θ R ;

[0099] Required solution: latitude and longitude of point B (X B , Y B ); latitude and longitude of point C (X C , Y C );

[0100] Solution method: First, solve the longitude and latitude of point C, and then use the known conditions to solve the turning segment in CD and VD to find the longitude and latitude of point C (X C , Y C ).

[0101] Point B latitude and longitude (X B , Y B ) will be solved by iteration method, input AB length D as 0.1, and compare D with (X C , Y C ) and θ into formula (1) to obtain the latitude and longitude of point B at this time. Substituting the latitude and longitude of point B at this time into formula (2) can calculate the VB direction θ at this time VB , add 0.1 to the original value of D and repeat the above steps again. Repeat the above steps until θ R With θ VB If the difference is less than 0.1, the latitude and longitude of point B at this time are output as the final (X B , Y B ).

[0102] The segment can be constructed by connecting AC with an arc and then connecting CB with a straight line.

[0103] 2.10、CI,VI segments:

[0104] The CI segment is to maintain the specified track until the next segment is interrupted, and the VI segment is to maintain the specified heading until the next segment is interrupted. Since the influence of wind will not be considered in the simulation of this embodiment, the heading and are the track, and the VI segment and the VI segment will be constructed using the same method.

[0105] According to the relationship between the path stop codes in the ARINC424 file, the CI and VI segments can be followed by AF, CF, FA, FC, FD, FM, and IF. When the next segment is CF, FA, FC, FD, FM, or IF, just use the starting point of the next segment as the stop point and then solve it according to the CF segment solution method. When the next segment is AF, the CI and VI segments can be regarded as stopping at a certain DME distance. At this time, the CI and VI segments are basically the same as the CD and VD segments, so the same solution method can be used.

[0106] 2.11、HA, HF, HM sectors:

[0107] HA, HF, and HM segments are all join-hold. First, you need to know the way to join the hold, which depends on which sector the hold track belongs to. The figure shows a schematic diagram of the holding route sector.

[0108] Given the known conditions of joining the waiting heading θ0, waiting for the entry heading θ, and waiting for the longitude and latitude (X, Y) of the positioning point HF, the method for determining the sector is as follows:

[0109] When the waiting direction is left waiting, if θ-110<θ0-180<θ, it is the first sector; when θ0≤180 or θ0>180 and 290≤θ≤360, if θ<θ0+180<θ+70, it is the second sector; when θ0>180 and 0≤θ≤180, if θ<θ0-180<θ+70, it is also the second sector. When the above conditions are not met, it is the third sector.

[0110] When the waiting direction is right waiting, if θ-70<θ0-180<θ, it is the second sector; when θ0≤180 or θ0>180 and 250≤θ≤360, if θ<θ0+180<θ+110, it is the first sector; when θ0>180 and 0≤θ≤180, if θ<θ0-180<θ+110, it is also the first sector. When the above conditions are not met, it is the third sector.

[0111] The schematic diagram of parallel joining of the first sector is as follows Fig.11 As shown in the figure, the heading of the straight flight segment from HF to point A is the waiting direction ±180°. This segment can be solved using the VA segment solution method. The only difference is that the total distance is the product of the flight speed V and the time T (one minute at this time). From point A to HF can be regarded as a DF segment (left waiting is a right turn, right waiting is a left turn), and the solution can be performed according to the DF segment.

[0112] The second sector bias addition diagram is as follows Fig.12 As shown in the figure, the heading from HF to point A is ±180° of the waiting direction and then ±30° (left waiting is plus, right waiting is minus). The calculation method is the same as that from HF to point A during parallel joining. The calculation method from point A to point HF can be calculated according to the CF segment calculation method. The only difference is that the turning direction is fixed at this time. Left waiting is a left turn, and right waiting is a right turn.

[0113] The third sector direct join solution method is: first use the parallel join solution method from HF to point A to solve the waiting position to the end of the flight, and then use the offset join solution method from HF to point A to solve the remaining track. The parallel join and offset join flight path after the second arrival at the waiting position HF are also solved by direct join.

[0114] In the HA, HF, and HM segment solutions, all turns without a fixed turning radius are standard turns.

[0115] The above-mentioned embodiments only express the specific implementation of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for generating an ideal trajectory of a chart program based on navigation database coding, characterized in that: include: The flight program is encoded according to the path abort code, and the corresponding program is converted into a series of segments in the navigation database according to the aeronautical chart and the coding table. The program in the navigation database is called to connect the series of segments together for solution, so as to obtain a complete flight plan; among them, the path abort code is used in the flight program to indicate the end of the flight path, and is used to indicate the action to be taken after completing a specific segment.

2. The method for generating an ideal trajectory of a chart program based on navigation database coding according to claim 1, characterized in that: During the solution process, the earth's surface is regarded as a plane, the preset route is planned as a straight line or arc on the local tangent plane, and various navigation parameters and guidance instructions are approximately calculated in this rectangular plane.

3. The method for generating an ideal trajectory of a chart program based on navigation database coding according to claim 2, characterized in that: When the calculated heading is greater than 360°, 360° is subtracted by default. When the calculated heading is less than 360°, the final result is obtained by subtracting the calculated value from 360°.

4. The method for generating an ideal trajectory of a chart program based on navigation database coding according to claim 1, characterized in that: The navigation database is in accordance with the ARINC424 standard of the navigation database standard format established by the Aviation Electronics Industry Association (ARINC).

5. The method for generating an ideal trajectory of a chart program based on navigation database coding according to claim 4, characterized in that: The flight segments include: CF segment, which means flying along a certain track to fly over or cut by a certain navigation station or positioning point; CA segment, which means keeping a certain track to a certain altitude; CI segment, which means keeping the route angle to cut into the next segment; IF segment, which means starting positioning point; TF segment, which means flying directly from one positioning point to another along a great circle route; DF segment, which means flying directly to a certain positioning point; FA segment, which means keeping the route angle from a certain positioning point to a certain altitude; FM segment, which means keeping the route angle from a certain positioning point to an artificial end point; RF segment, which means turning to a positioning point with a fixed radius; HF segment, which means waiting at a certain positioning point; HA segment, which means waiting at a certain positioning point to climb to another altitude; HM segment, which means waiting at a certain positioning point until artificial termination; VA segment, which means keeping the heading to a certain altitude; VI segment, which means waiting at a certain positioning point until artificial termination; A segment means maintaining a heading until the next segment is entered; a VM segment means maintaining a heading until the artificial end point; an FC segment means flying along a certain track to a point at a specified distance from the navigation station or positioning point; an FD segment means flying along a certain track to a specified DME distance; a PI segment means a procedure turn, which is used for right-angle procedures; a CD segment means flying along a certain track to a specified DME distance and then crossing it; a CR segment means flying along a certain track to a specified radial line of a VOR navigation station; an AF segment means flying along the DME arc from an uncertain positioning point on the DME arc to the next positioning point; a VD segment means flying from the previous waypoint to a point at a specific DME distance at a certain heading; a VR segment means flying from the previous waypoint to a specific VOR radial line at a certain heading.

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