CN104457735A - 4D trajectory displaying method based on World Wind - Google Patents

Abstract

The invention discloses a 4D trajectory displaying method based on World Wind. The 4D trajectory displaying method based on World Wind comprises the following steps of disposing flight dynamic data of an aircraft; converting projection coordinates of the aircraft so as to obtain the projection position; introducing control airspace GIS data so as to obtain an airspace background; combining the projection position of the aircraft and the airspace background so as to obtain the projection position of the aircraft with the combination of the airspace background; and displaying the flight dynamic data of the aircraft in the form of comprehensive information and the like. According to the method disclosed by the invention, the three-dimensional airspace background of a display subsystem is rendered by utilizing a World Wind platform; the dynamic information of the aircraft is displayed by adopting a transparent target layer, and the position of the aircraft at the target layer is consistent with the three-dimensional airspace background by adopting a space conversion mode, so that relatively intuitive airspace dynamic information can be provided for managers, and the effectiveness and reliability of air traffic control can be improved.

Description

Based on the 4D Target track displaying method of World Wind

Technical field

The invention belongs to display technique field, particularly relate to the four-dimensional Target track displaying method of blank pipe command system.

Background technology

The aircraft four-dimension (4Dimensional, being called for short 4D) flight path is the method for the locus (longitude, latitude and height) run aircraft with room and time form and time carrying out accurate description, U.S. air traffic control system (ATCS) (Next Generation Air Transportation System of future generation, one of be called for short NEXTGEN) and European sky integration blank pipe research (Single European Sky ATM Research, abbreviation SESAR) the important support technology of planning.Operation based on 4D flight path significantly can reduce the uncertainty of aircraft flight path, improves security and the utilization factor of spatial domain and Airport Resources.Meanwhile, 4D flight path is all significant in flight collision research, AIRSPACE PLANNING, trajectory planning, flight simulation, blank pipe support and air-accident investigation are analyzed.

Target track displaying is shown in real time on a monitor the current location of aircraft and flight path, dynamic with the aircraft making air traffic controller understand in time in control zone, to avoid driftage and conflict.The display of existing Civil Aviation ATM command system to aircraft 4D flight path information adopts two-dimentional Dynamic Announce pattern, namely the horizontal distribution situation of aircraft in control zone can only be demonstrated over the display intuitively, the elevation information of aircraft by label form digitized representation, by presenting its temporal information to the refreshing of aircraft position information.Controller needs in brains, reconstruct real three-dimensional dynamic scene to the control of relative position between aircraft, and this is higher to the technical requirement of controller, difficulty is comparatively large, is unfavorable for carrying out control to high density aircraft.The appearance of a new generation's air traffic control system (ATCS) (NEXTGEN and SESAR) and application, have higher requirement to the 4D flight path management of aircraft.Such as: in air traffic control system (ATCS) of new generation, for consideration that is energy-conservation and noise reduction, employing continuous decrease is entered nearly technology and guide aircraft lands, this requires that controller grasps more accurately to being in have into the 4D flight path of nearly stage aircraft.And current two-dimentional Dynamic Announce pattern is difficult to this requirement competent, need to explore aircraft 4D Target track displaying method that is new, that be more suitable for air traffic control system (ATCS) of new generation.

At aircraft 4D Target track displaying technical elements, Chinese scholars has carried out a large amount of useful exploration.Some scholars are studied the feasibility of aircraft 4D Target track displaying and using value, as: Below etc. have carried out attempting application to 4D flight path in cockpit display system, assess 4D Target track displaying and flight safety; Teutsch etc. have inquired into the application feasibility of 4D flight path at following air traffic control system, study in the management and control ability of the different mission phase of aircraft controller, set forth the using value of 4D flight path at air traffic control automation system; Lin etc. establish three-dimensional real-time target positioning track display prognoses system, for monitoring the running orbit of terrain object and making a prediction, for the supervision of 4D flight path surveillance provides theoretical foundation.Above-mentioned research does not carry out in-depth explanation to 4D Target track displaying know-why.Zhang Zhi is quick etc. sets up real-time Target track displaying system, temporal information is introduced two-dimentional Target track displaying, in conjunction with map three-point fix principle, uses overall background roaming technology to improve display positioning precision.Although this research achieves the real-time display of flight path, but still be confined to traditional two dimensional surface display.Some scholars are also had to propose three-dimensional geographic information system (Geographic Information System is called for short GIS) to introduce in the display of blank pipe command system.Lin etc. have studied implementation method and the key technical problem of three-dimensional track surveillance; Cui Wen etc. set up based on the flight path plotting system of GIS assembly, to pacify the good etc. to have studied the using value of GIS in radar asorbing paint control system.Above-mentioned achievement shows that three-dimension GIS has vital role in the aircraft 4D flight path of blank pipe command system.Three-dimensional visualization numeral GIS browing system---World Wind---that Tian Lianghui etc. utilize NASA (NASA) to develop establishes aircraft simulation track 3D demo system, for carrying out analog demenstration to the space flight state of aircraft.

For air traffic control system (ATCS) of new generation, due to the fine-grained management to aircraft 4D flight path, need controller to have the relative position between the aircraft in responsible spatial domain and control more intuitively.The intuitive technique of display aircraft 4D flight path utilizes dynamic three-dimensional display system to realize, and three-dimensional display system increases multidate information.Current more ripe dimension display technologies, as light splitting anaglyph spectacles, line holographic projections etc., good 3-D effect can be realized, but utilize the display system of these technique constructions to be easy to cause fatigue to user, be unsuitable for long-time use, therefore, the display subsystem of the air traffic control system (ATCS) of new generation both aircraft 4D flight path of demand fulfillment to display possesses 3-D effect directly perceived, meets the requirement that controller can work for a long time before display system again.

Summary of the invention

In order to solve the problem, the object of the present invention is to provide a kind of 4D Target track displaying method based on World Wind that can meet air traffic control system (ATCS) display subsystem of new generation actual demand.

In order to achieve the above object, the 4D Target track displaying method that the invention provides based on World Wind comprises the following step sequentially carried out:

(1) the S1 stage that the aircraft dynamic data transferred blank pipe command system arranges;

(2) aircraft projection coordinate is converted, to obtain the S2 stage of its projected position;

(3) control zone GIS data is introduced, to obtain the S3 stage of spatial domain background;

(4) the spatial domain background that aircraft projected position above-mentioned steps (2) obtained and step (3) obtain is synthesized, to obtain the S4 stage of the aircraft projected position combining spatial domain background;

(5) according to the aircraft projected position combining spatial domain background that step (4) is determined, the aircraft dynamic data of step (1) storage and management is carried out S5 stage of showing with integrated information form.

In step (1), the method that the described aircraft dynamic data transferred blank pipe command system arranges to coordinate hands over data specification and European monitoring data between air traffic control radar and Control Centre's facility and transfer the aircraft dynamic data that standard specifies by meeting and store with structure form, and manage with Hash table and chain sheet form, aircraft dynamic data comprises identifying information, flight dynamic data, temporal information and further feature information.

In step (2), described converts aircraft projection coordinate, is that the longitude of aircraft, latitude, elevation information to be transformed to according to WGS-84 co-ordinated standard with the earth's core be the model coordinate systems coordinate of initial point to obtain the method for its projected position; Then with earth surface point corresponding to display screen center for initial point builds world coordinate system, and aircraft coordinate is converted to world coordinates by model coordinate; Build projected coordinate system according to virtual image space relation, the world coordinates of aircraft is converted to the projection coordinate that screen shows.

In step (3), described introducing control zone GIS data, with obtain the method for spatial domain background be by NASA develop World Wind dynamic three-dimensional display system platform as a setting, utilize its external interface earth's surface altitude figures and texture to be loaded in system.

In step (4), the spatial domain background that described aircraft projected position above-mentioned steps (2) obtained and step (3) obtain is synthesized, place a transparent destination layer in the front of dynamic three-dimensional display background layer to obtain the method for the aircraft projected position combining spatial domain background, destination layer marks the position of the pocket that sails, aircraft is in the background environment of actual spatial domain.

In step (5), the described aircraft projected position combining spatial domain background determined according to step (4), aircraft dynamic data step (1) stored and manage is the aircraft projected position combining spatial domain background determined according to step (4) with the method that integrated information form carries out showing, the aircraft dynamic data utilizing aircraft identification information retrieval to go out step (1) to store and manage, and these data are drawn in destination layer with the tail of aircraft, label form.

4D Target track displaying method based on World Wind provided by the invention, can also be compatible with traditional display subsystem pattern well while realization is to aircraft 4D flight path dynamic three-dimensional display.The method utilizes the three-dimensional spatial domain background that World Wind platform is display subsystem to play up, adopt the multidate information of transparent objects layer to aircraft to show, and make aircraft consistent with three-dimensional spatial domain background in the position of destination layer by the mode of spatial alternation.The inventive method utilizes ADS-B to gather the real-time dynamic information of aircraft in spatial domain as experiment information source, shows the 4D flight path of aircraft.Experimental result shows, the 4D Target track displaying technology proposed and conventional aerial traffic display technique compatibility, and can provide spatial domain multidate information more intuitively for keeper, is conducive to the validity and reliability improving air traffic control.

Accompanying drawing explanation

Fig. 1 is the 4D Target track displaying method flow diagram based on World Wind provided by the invention;

Fig. 2 is view coordinate schematic diagram;

Fig. 3 is transparent objects layer and Background From Layer graph of a relation;

Fig. 4 is aircraft intergrated information display schematic diagram;

Fig. 5 is control zone multi-target traces vertical view;

Fig. 6 is control zone multi-target traces side view;

Fig. 7 is certain targetpath partial enlarged drawing in Fig. 6.

Embodiment

Below in conjunction with the drawings and specific embodiments, the 4D Target track displaying method based on World Wind provided by the invention is described in detail.

Fig. 1 is the 4D Target track displaying method flow diagram based on World Wind provided by the invention.

As shown in Figure 1, the 4D Target track displaying method based on World Wind provided by the invention comprises the following step carried out in order:

(1) the S1 stage that the aircraft dynamic data transferred blank pipe command system arranges:

Aircraft dynamic data needed for display is distributed to display subsystem by LAN (Local Area Network) by blank pipe command system.According to coordinating the regulation such as hands over data specification (MH/T 4008-200) and European monitoring data transfer standard (SUR.ETI.ST05.2000-STD-09-01) between air traffic control radar and Control Centre's facility, aircraft dynamic data mainly comprises:

1) identifying information: this information can be unique 24 identification codes of every frame aircraft of ICAO regulation, also can be 12 identification codes that airborne secondary radar answering machine provides;

2) fly dynamic data: the information mainly comprising the real-time change such as the three-dimensional position of aircraft, ground velocity, climbing speed, angle of deviation, the emergency circumstance;

3) temporal information: refer to be distributed to the temporal information comprised in the packet of display subsystem, this information is for marking the moment producing in packet and put mark or flight path report.Blank pipe command system can receive the flight dynamic data generated from different sensors (as aviation management primary radar, navigation management secondary radar, ADS-B etc.).The acquisition of these data in time, spatially asynchronous, for synchronously processing in display subsystem, need mark report produce temporal information;

4) further feature: this kind of information spinner will comprise flight number, aircraft type etc., this category information is used for the aid illustration to aircraft usually, substantially constant in aircraft whole process.

Utilize above-mentioned information can by the generation necessary position of aircraft 4D flight path, history tail, velocity magnitude and direction, highly, the information such as identification.

The present invention adopts the key message of Hash table form to above-mentioned aircraft 4D flight path to manage, and the key attribute using the identifying information of aircraft as Hash table, the division of realize target.In spatial domain aircraft increasing, to subtract and follow the tracks of be managed by modes such as the establishment to Hash table object, deletion and renewals.

(2) aircraft projection coordinate is converted, to obtain the S2 stage of its projected position:

In spatial domain, the position of aircraft usually utilizes its longitude, latitude and highly represents, because the display subsystem at blank pipe command system adopts flat-panel screens, aircraft needs to provide its position at screen prjection with the form of screen coordinate, therefore needs the geodetic transformation of aircraft to screen prjection coordinate form.

Suppose to be distributed to longitude, the latitude of certain aircraft of display subsystem by blank pipe command system and to be highly respectively α, β and h.World Wind with the earth centre of sphere for initial point builds earth model coordinate system.The z-axis sensing arctic identical with earth's axis of this coordinate, x-y plane is positioned at the equatorial plane, and x-axis is through Greenwich meridian.Under WGS-84 coordinate-system, the coordinate (x of aircraft in model coordinate systems _m, y _m, z _m) be:

$\left\{\begin{array}{c}{x}_m=(r+h)\cos \mathrm{\α}\cos \mathrm{\β}\\ y_m=(r+h)\sin \mathrm{\α}\cos \mathrm{\β}\\ z_m=[r(1-e^2)+h]\sin \mathrm{\β}\end{array}\right.---\left(1\right)$

Wherein, r is equivalent redius:

$r=\frac{R_e}{{\left({1-e}^2{\sin }^2\mathrm{\β}\right)}^{1/2}}---\left(2\right)$

E=0.0818 is eccentricity of the earth, R _efor terrestrial equator radius, R _e=6378137 meters.In World Wind, the rotation translation of three-dimensional scenic all can not affect the position of aircraft in model coordinate systems.

Earth surface point corresponding to indicator screen center is considered as initial point, and structure world coordinate system, the coordinate axis that each coordinate axis of this coordinate system is corresponding with on earth model coordinate system is parallel.The coordinate of initial point in earth model coordinate system of world coordinate system is (x ₀, y ₀, z ₀), then aircraft is (x in the position of world coordinate system _w, y _w, z _w).Consider the impact of translation in conversion between different coordinates, each coordinate is expressed as (x _m, y _m, z _m, 1) and (x _w, y _w, z _w, 1), then both sides relation is:

$\left[\begin{array}{c}{x}_w\\ y_w\\ z_w\\ 1\end{array}\right]=\left[\begin{array}{cccc}1& 0& 0& -x_0\\ 0& 1& 0& -y_0\\ 0& 0& 1& {-z}_0\\ 0& 0& 0& 1\end{array}\right]\left[\begin{array}{c}{x}_m\\ y_m\\ z_m\\ 1\end{array}\right]---\left(3\right)$

With virtual observation point for initial point (position as camera in Fig. 2 1) towards and perpendicular to projection plane for z-axis, the horizontal direction being parallel to projection plane is x-axis, form view coordinate, the coordinate of aircraft in view coordinate is expressed as (x _c, y _c, z _c, 1):

$\left[\begin{array}{c}{x}_c\\ y_c\\ z_c\\ 1\end{array}\right]=M_2\·M_1\·\left[\begin{array}{c}{x}_w\\ y_w\\ z_w\\ 1\end{array}\right]---\left(4\right)$

Wherein, M ₁for the transformation matrix of camera 1, concrete form is:

$M_1={\left[\begin{array}{cccc}{\sin \mathrm{\α}}_c& -{\sin \mathrm{\α}}_c\sin {\mathrm{\β}}_c& -\cos {\mathrm{\α}}_c\cos {\mathrm{\β}}_c& 0\\ -{\cos \mathrm{\α}}_c& -\cos {\mathrm{\α}}_c\sin {\mathrm{\β}}_c& -{\sin \mathrm{\α}}_c\cos {\mathrm{\β}}_c& 0\\ 0& \cos {\mathrm{\β}}_c& -\sin {\mathrm{\β}}_c& 0\\ r_c\cos {\mathrm{\α}}_c\cos {\mathrm{\β}}_c& r_c\sin {\mathrm{\α}}_c\cos {\mathrm{\β}}_c& r_c\sin {\mathrm{\β}}_c& 1\end{array}\right]}^T---\left(5\right)$

[] ^trepresenting matrix matrix transpose operation, α _c, β _cand r _crepresent the longitude of camera 1, latitude and camera 1 distance to ground respectively, M ₂for rotation matrix:

the angle rotated along the x-axis of view coordinate and z-axis is represented respectively with θ.

Virtual image space V under view coordinate be by front find a view face S1 and after the conical region that face S2 cuts out of finding a view form, as shown in Figure 2.Face S1 found a view in the past as projecting plane, and the z-axis of view coordinate and the point on projecting plane are as the initial point of projected coordinate system, and the x-axis of projected coordinate system and y-axis are parallel to x-axis and the y-axis of view coordinate respectively.(x in view coordinate _c, y _c, z _c, 1) and place's aircraft is hand over the point on projecting plane to determine by view coordinate initial point and aircraft line at the coordinate on projecting plane, the therefore projection coordinate of aircraft and x _cand y _clinear, with z _cin reciprocal relation.Triangular transformation is utilized to obtain:

$\left[\begin{array}{c}{x}_p^{\′}\\ y_p^{\′}\\ r_p\end{array}\right]=\left[\begin{array}{cccc}{s}_w/2& 0& 0& 0\\ 0& s_h/2& 0& 0\\ 0& 0& \tan (\mathrm{\φ}/2)& 0\end{array}\right]\·\left[\begin{array}{c}{x}_c\\ y_c\\ z_c\\ 1\end{array}\right]---\left(7\right)$

S in formula _wand s _hfind a view before representing respectively the width of face in view coordinate and height, φ is visual angle size, and in three-dimensional display system, φ is normally fixing, x ' _pwith y ' _pfor not utilizing z _ccarry out the projection coordinate before nonlinear transformation, 1/r _pfor projection coordinate's scaling coefficient, so the coordinate of aircraft on projecting plane is:

$\left\{\begin{array}{c}{x}_p=x_p^{\′}/r_p\\ y_p=y_p^{\′}/r_p\end{array}\right.---\left(8\right)$

Projection coordinate (the x of the aircraft utilizing formula (8) to obtain _p, y _p) can be implemented in the location to aircraft on transparent objects layer.

(3) control zone GIS data is introduced, to obtain the S3 stage of spatial domain background:

What the display subsystem of blank pipe command system adopted is integrated display, it will relate to the key element of navigation safety, as airport, the navigation station, course line, special spatial domain, barrier etc. are integrated into the background information of aircraft battle state display, enable controller grasp airspace operation situation more clearly.The air traffic control system (ATCS)s of new generation such as the SESAR in the NEXTGEN of the U.S. and Europe all require to the management of aircraft by based on time management to developing based on flight path management orientation, this requires that on the one hand display subsystem should be able to provide the dynamic three-dimensional display of control zone for controller, also require that display subsystem can provide the background information of more horn of plenty on the other hand, special needs introduce GIS information in the terminal area of near airports, as data elevation model (Digital Elevation Model, vehicle economy M) information, map image information etc., for display terminal regional landforms information.

The World Wind system that the present invention utilizes NASA to develop is as the background platform of blank pipe command system dynamic three-dimensional display.World Wind possesses the three-dimensional graphics renderer mechanism of Direct3D engine, can carry out playing up of image, model etc. on earth model.World Wind also provides the data-interface of XML file form, and by this interface, local map tile segmentation image and DEM altitude figures can be loaded in World Wind platform.The aircraft be shown as in commander spatial domain of three-dimension GIS provides target surrounding reference, can directly be judged periphery landform and environment etc., enrich the displaying contents of blank pipe command system, reduce the what comes into a driver's gap of controller and pilot, thus improve Effectiveness of Regulation and accuracy.

Other control information such as weather nephogram, radar signal strength can also be loaded by the XML file interface of World Wind, enrich the background information of blank pipe command system dynamic three-dimensional display further.

(4) the spatial domain background that aircraft projected position above-mentioned steps (2) obtained and step (3) obtain is synthesized, to obtain the S4 stage of the aircraft projected position combining spatial domain background:

The control zone background information that the aircraft that step (2) obtains projected position on the display screen needs and step (3) generates is harmonious, and aircraft is properly positioned in background environment by display subsystem.As described in step (3), World Wind can adopt XML file form to receive external data and load, but the positional information of aircraft is unsuitable for and adopts this interface to load, and reason is that the three-dimensional scenic of World Wind is played up by Direct3D engine renders.Scene information changes and will trigger Direct3D engine and again play up scene.When aircraft position information is loaded by XML file interface, Direct3D engine will be triggered.Because the updating location information of aircraft is frequent, and spatial domain internal object number is more, adopts the method frequently can trigger Direct3D engine.Direct3D engine renders process computation complexity is high, time load large, is unsuitable for frequently calling.

Method provided by the invention places one deck in the front of three-dimensional scenic display layer L2 for drawing the transparent destination layer L1 of target dynamic, as shown in Figure 3.Dynamically playing up three-dimensional scenic to upgrade with aircraft multidate information and be separated, thus Direct3D engine is only called when three-dimensional scenic changes, and the renewal of target dynamic information can not trigger Direct3D engine.

The introducing of destination layer L1 solves Direct3D engine and frequently calls problem by target update informational influence, decreases the time load of aircraft dynamic drafting, ensures the real-time of aircraft 4D Target track displaying.About the consistency problem of aircraft in the position that destination layer shows and three-dimensional scenic position, method provided by the invention adopts the coordinate system that change synchronous with step (3) in step (2).

(5) according to the aircraft projected position combining spatial domain background that step (4) is determined, the aircraft dynamic data of step (1) storage and management is carried out S5 stage of showing with integrated information form:

The synthesis display information of aircraft comprises aircraft current location, history flight path, flight label, projection line and speed line etc., by the Display Realization of these information to the description of aircraft 4D flight path.

The present invention is according to the identifying information of each aircraft, object retrieval in the Hash table that step (1) is managed, obtain the flight dynamic data in aircraft a period of time, and utilize these data to generate corresponding rendering parameter according to the information displaying classification such as tail, label of aircraft, and draw on destination layer L1 centered by the aircraft projected position combining spatial domain background determined by step (4), as shown in Figure 4, the intergrated information display task of aircraft is completed.

Experimental result

4D Target track displaying method based on World Wind provided by the invention can be further illustrated by following experiment.

Experiment adopt data source be ADS-B receiver real-time reception spatial domain, Beijing in aircraft dynamic data.These dynamic datas comprise ICAO identification code, secondary radar identification code, real-time three-dimensional positional information (longitude, latitude, highly), velocity information, course information, temporal information etc.

4D Target track displaying method based on World Wind provided by the invention overlook design sketch as shown in Figure 5.In figure, larger black circle identifies the current location of aircraft, corresponding label provides identifying information and the information such as speed, height of aircraft, the some points be connected with aircraft by broken line represent the historical position of aircraft, and the line of these positions defines the tail information of aircraft.As seen from Figure 5, the 4D Target track displaying method based on World Wind provided by the invention deteriorates to the display mode compatible mutually with existing display packing when overlooking.

When adopting stravismus, the 4D Target track displaying method based on World Wind provided by the invention to aircraft 4D Target track displaying as shown in Figure 6.Fig. 6 is that comparatively large scene shows situation, and Fig. 7 is the situation that in Fig. 6, localized target amplifies display.Compared with Fig. 5, in Fig. 6, the display of aircraft adds projection line, thus can more intuitively for controller provides the elevation information of aircraft.And the three-dimension GIS information that World Wind introduces more can assist controller to grasp the dynamic of control zone.

Experimental result shows, spatial domain geography information that 4D Target track displaying method based on World Wind provided by the invention is both perfect, realize again the breakthrough of flight path 3-D display, controller can be assisted more clearly to grasp mutual alignment in spatial domain between each aircraft, improve the validity and reliability of air traffic control.

Claims (6)

1. based on a 4D Target track displaying method of World Wind, it is characterized in that, the described 4D Target track displaying method based on World Wind comprises the following step carried out in order:

(1) the S1 stage that the aircraft dynamic data transferred blank pipe command system arranges;

(2) aircraft projection coordinate is converted, to obtain the S2 stage of its projected position;

(3) control zone GIS data is introduced, to obtain the S3 stage of spatial domain background;

(4) the spatial domain background that aircraft projected position above-mentioned steps (2) obtained and step (3) obtain is synthesized, to obtain the S4 stage of the aircraft projected position combining spatial domain background;

(5) according to the aircraft projected position combining spatial domain background that step (4) is determined, the aircraft dynamic data of step (1) storage and management is carried out S5 stage of showing with integrated information form.

2. the 4D Target track displaying method based on World Wind according to claim 1, it is characterized in that: in step (1), the method that the described aircraft dynamic data transferred blank pipe command system arranges to coordinate hands over data specification and European monitoring data between air traffic control radar and Control Centre's facility and transfer the aircraft dynamic data that standard specifies by meeting and store with structure form, and manage with Hash table and chain sheet form, aircraft dynamic data comprises identifying information, flight dynamic data, temporal information and further feature information.

3. the 4D Target track displaying method based on World Wind according to claim 1, it is characterized in that: in step (2), described converts aircraft projection coordinate, is that the longitude of aircraft, latitude, elevation information to be transformed to according to WGS-84 co-ordinated standard with the earth's core be the model coordinate systems coordinate of initial point to obtain the method for its projected position; Then with earth surface point corresponding to display screen center for initial point builds world coordinate system, and aircraft coordinate is converted to world coordinates by model coordinate; Build projected coordinate system according to virtual image space relation, the world coordinates of aircraft is converted to the projection coordinate that screen shows.

4. the 4D Target track displaying method based on World Wind according to claim 1, it is characterized in that: in step (3), described introducing control zone GIS data, with obtain the method for spatial domain background be by NASA develop World Wind dynamic three-dimensional display system platform as a setting, utilize its external interface earth's surface altitude figures and texture to be loaded in system.

5. the 4D Target track displaying method based on World Wind according to claim 1, it is characterized in that: in step (4), the spatial domain background that described aircraft projected position above-mentioned steps (2) obtained and step (3) obtain is synthesized, place a transparent destination layer in the front of dynamic three-dimensional display background layer to obtain the method for the aircraft projected position combining spatial domain background, destination layer marks the position of the pocket that sails, aircraft is in the background environment of actual spatial domain.

6. the 4D Target track displaying method based on World Wind according to claim 1, it is characterized in that: in step (5), the described aircraft projected position combining spatial domain background determined according to step (4), aircraft dynamic data step (1) stored and manage is the aircraft projected position combining spatial domain background determined according to step (4) with the method that integrated information form carries out showing, the aircraft dynamic data utilizing aircraft identification information retrieval to go out step (1) to store and manage, and by these data with the tail of aircraft, label form is drawn in destination layer.