A dynamic management method for train track map
The dynamic management of train track maps using longitude and latitude for initial station determination and circular list updates addresses memory and time inefficiencies, improving the stability and real-time performance of train positioning systems.
Patent Information
- Application Number
- CN202111570791.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-21
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2041-12-21
AI Technical Summary
Current track map management technologies in train positioning systems are time-consuming and memory-intensive, occupying significant local memory and failing to meet the demands of increasing railway operations with larger and more complex track maps.
A dynamic management method for train track maps that determines the initial station based on longitude and latitude, constructs a local map list with a circular structure, and dynamically updates maps based on train direction, storing only the current, previous, and next station maps in the local memory.
This method significantly reduces preprocessing time, saves memory space, and enhances the stability and real-time performance of the positioning system by optimizing map storage and retrieval.
Smart Images
Figure CN114049050B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a dynamic management method of a train track map used in a train satellite navigation and positioning system. Background Art
[0002] At present, the global navigation satellite system (GNSS) is increasingly being used in train positioning systems. The GNSS train positioning system cannot do without the management of track maps. The track map downloaded from the TSRS center only contains the longitude and latitude of the track POI points and cannot be directly used for positioning projection. It needs to be pre-processed by the train (such as calculating the direction vector of the straight track, calculating the center and diameter of the curved track, etc.) and stored in the local memory before it can be used for positioning. Most of the current track map management technologies pre-process the entire line track map and store it locally before it can be used for positioning. This method is not only time-consuming, but also greatly occupies the local memory of the on-board software, making the software more dependent on the platform memory. As the railway operation tasks become increasingly heavy, the track maps that need to be stored and processed are also getting larger and larger. The existing track map processing methods can no longer meet the needs of the booming industry. Summary of the invention
[0003] The purpose of the present invention is to provide a dynamic management method for a train track map, which saves track map preprocessing time, reduces track map storage space, saves software memory space and running time, and improves the stability of a positioning system.
[0004] In order to achieve the above-mentioned purpose, the present invention provides a dynamic management method of a train track map, which determines the initial current station where the train is located according to the longitude and latitude of the initial position of the train and the longitude and latitude of the starting and ending points of each station, obtains the track map of the initial current station, the station in front of the initial current station and the station behind the initial current station and stores them in the local memory of the train, and after the train determines the running direction, obtains the track map of the rear station of the rear station that the train is about to arrive at in real time according to the running direction of the train and stores it in the local memory of the train.
[0005] A local map list is constructed in the local memory of the train for storing the track map; the local map list can store the track maps of m stations, where m≥3, and m is an odd number.
[0006] The local map list is a circular list.
[0007] When the train is running in the forward direction, the local map list is updated in a counterclockwise direction in a sequence from top to bottom. When the train is running in the reverse direction, the local map list is updated in a clockwise direction in a sequence from bottom to top.
[0008] The track map of the initial current station is stored in the middle position of the local map list.
[0009] The track map of the station ahead of the initial current station and the track map of the station behind the initial current station are respectively stored in the local map list at adjacent positions of the track map of the initial current station.
[0010] If there is no station ahead of the current station or no station behind the current station, the corresponding position in the local map list is empty.
[0011] The acquired track map of the rear station of the rear station is stored in a blank position in the local map list.
[0012] If there is no blank position in the local map list, the track map of the station farthest from the current station in the reverse direction of the train running stored in the local memory of the train is updated to the track map of the rear station of the rear station just obtained.
[0013] The original map of each station is pre-obtained and stored in the local memory of the train.
[0014] The method for determining the initial current station where the train is located includes:
[0015] Traverse the original map of each station and determine that the longitude and latitude of the train's initial position point P is within the range of the longitude and latitude of the starting and ending points of a certain station K;
[0016] The track of station K is simplified into a line segment AB with starting point A and end point B. The perpendicular point Q from the initial position point P of the train to the line segment AB is calculated. If point Q is on the line segment AB, station K is determined to be the initial current station of the train.
[0017] The original map is stored in the power-off protection area of the local memory of the train.
[0018] According to the station number on the original map, determine whether the train's initial current station has a front station and a rear station.
[0019] The method for obtaining the track map comprises: obtaining the straight track and the curved track of the station from the original map, calculating the direction vector of the straight track, and calculating the center and diameter of the curved track.
[0020] The present invention has the following advantages:
[0021] 1. The initial position of the train is determined only by the longitude and latitude of the starting and ending points between stations. There is no need to pre-process the track maps of all stations before starting positioning, which greatly saves the time required for the initial positioning of the train and improves the availability of the train positioning system.
[0022] 2. Pre-process the track map of the next station of the train according to the train running trajectory, saving software running time and improving the stability of the positioning system.
[0023] 3. A method of dynamically storing maps is defined, which only stores the track maps of the previous station, current station and next station in the direction of the train's operation, saving software memory space, greatly reducing the software's dependence on platform memory, and also improving the real-time performance of the positioning system in managing maps. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 This is the flow chart of the initial positioning of the train.
[0025] Figure 2 Flowchart for managing the stored map after determining the initial position for the train.
[0026] Figure 3 Flowchart for dynamically managing stored maps after determining the running direction for the train.
[0027] Figure 4 Schematic diagram of storing local map lists for dynamic management of trains. DETAILED DESCRIPTION
[0028] The following is based on Figure 1 to Figure 4 , specifically describe the preferred embodiments of the present invention.
[0029] The present invention provides a dynamic management method for a train track map of a train satellite navigation and positioning system, which is implemented in the train satellite navigation and positioning system. The dynamic management method specifically comprises the following steps:
[0030] Step S1, downloading the original map, obtaining the original map file of each station, wherein the original map file stores information such as the station number and longitude and latitude, and storing the original map file in the power-off protection area of a storage device, wherein the storage device is usually a Flash memory;
[0031] Step S2, roughly determining the initial position of the train according to the longitude and latitude obtained by the train and the starting and ending longitude and latitude of each station in the original map;
[0032] Step S3: Get the track map from the original map and pre-process the station where the current train is located. [K] The track map of the vehicle, the preprocessing includes: calculating the direction vector of the straight track, calculating the center and diameter of the curved track, etc.;
[0033] Step S4: Set the current station [K] The track map is stored in the local map list L of the on-board software n(The local map list can store map files of up to m stations, m ≥ 3, and m is an odd number, n = 0, 1, ..., m-1) in the middle position, that is, L [n / 2] Where, " / " means integer division;
[0034] Step S5: Using L in the local map list [n / 2] The Station stored at [K] Station track map for accurate train positioning;
[0035] Step S6: Determine the station where the train is located based on the station number on the original map [K] Is there a forward station? If yes, pre-process the forward station Station [K-1] The track map is then stored in the local map list L [n / 2 -1] If there is no track map for the next station, then L in the local map list [n / 2 -1] The track map is empty;
[0036] Step S7: Determine the station where the train is located based on the station number on the original map. [K] Is there a rear station? If yes, pre-process the rear station Station [K+1] The track map is then stored in the local map list L [n / 2+1] If there is no track map for the following station, then L in the local map list [n / 2+1] The track map is empty;
[0037] Step S8: Dynamically update the map according to the train running direction. If the train is running in the forward direction, the train location is determined by Station [K] Enter Station [K+1] If the station is running in the station direction, the rear station Station is read from the power-off protection area. [K+2] Station track map file, pre-processing, and then enter step S9; if the train runs in the reverse direction, the train positioning is determined by the Station [K] Station Enter Station [K-1] Station, then read the previous station Station from the power-off protection area [K-2] The track map file of the station is pre-processed, and then the process goes to step S10;
[0038] Step S9: Since the train is at Station [K+1] Station, then clear Station [K+1] Station location local map list L [n / 2+1] The track map in the local map list of the next station at the location, that is, clear the local map list L[((n / 2+1)+1)％n] The track map stored at the station [K+2] Station track maps are stored in the local map list L [((n / 2+1)+1)％n] Where, “%” means remainder.
[0039] Step S10: Since the train is at Station [K-1] Station, then clear Station [K-1] Station location local map list L [n / 2 -1] The map in the local map list of the previous station, that is, clear the local map list L [((n / 2 -1)-1+n)％n] The track map stored at the station [K-2] Station track maps are stored in the local map list L [((n / 2 -1)-1+n)％n] Place.
[0040] Step S11, and so on, according to the current station of the train [p] The track map is located in the local map list L [q] and the direction of the train, and update the map of the next stop of the train in the local map list in advance.
[0041] The step S2 specifically comprises the following steps:
[0042] Step S12, traverse each station in the original map, and determine whether the longitude and latitude obtained by the train are within the range of the starting and ending longitude and latitude of a certain station in the original map;
[0043] Step S13: If a station that satisfies step S12 is found, it is considered that the track of the station can be simplified to a starting point A (Lat a ,Lon a ), the end point is B(Lat b ,Lon b ) and the train position is point P(Lat p ,Lon p ). Calculate the foot of the perpendicular Q (Lat q ,Lon q ), if the coordinates of point Q are within the range of line segment AB, the train is considered to be initially located at Station [K] stand.
[0044] Example
[0045] refer to Figure 1 , explaining the method for the train to determine its initial position.
[0046] Step 100, traverse each station in the original map and find the latitude and longitude of a station K that meets the conditions: Station [K] Longitude of starting point A - Lon 阈值 ≤Longitude of train position point P≤Station [K] Longitude of end point B + Lon 阈值 , and Station [K] Latitude of starting point A - Lat 阈值 ≤Latitude of train location point P≤Station [K] Latitude of end point B +Lat 阈值 , where the two thresholds Lon 阈值 and Lat 阈值 It is an empirical value obtained from experiments. Since the signal strength and the actual longitude and latitude of the error train may deviate within a certain range, the threshold is added to provide a certain redundancy. For example, 1.01 is not between 0 and 1, but between -0.1 and 1.1, so it is roughly considered that 1.01 is between 0 and 1.
[0047] Step 101, the train position is represented as point P (Lat p ,Lon p ), Station [K] Starting point A(Lat a ,Lon a ) and Station [K] End point B (Lat b ,Lon b ) as a line segment; use mathematical formulas to calculate the foot coordinates Q (Lat q ,Lon q ), if Lat a ≤Lat q ≤Lat b , and Lon a ≤Lon q ≤Lon b , then the train is considered to be initially located at Station [K] stand.
[0048] refer to Figure 2 , which illustrates the principle of storing a local map after the train determines its initial position.
[0049] Step 102: Preprocess the station where the current train is located [K] Track map;
[0050] Step 103, set the current station Station [K] The track map is stored in the local map list L of the on-board software n(The local map list can store map files of up to m stations, m ≥ 3, and m is an odd number, n = 0, 1, ..., m-1) in the middle position, that is, L [n / 2] Where, " / " means integer division;
[0051] If the onboard software has more memory, more station rail maps can be saved in the local map list. If the onboard software has less memory, at least three station rail maps need to be saved in the local map list. For example, when m=3, the local map list is L[0]-L[2], and the current station is Station [K] The track map is stored in the middle list L[1]. When m=5, the local map list is L[0]-L[4]. The current station is Station [K] The track map is stored in the list L[2] in the middle position;
[0052] Step 104: Determine the station where the train is located based on the station number on the original map. [K] Is there a forward station? If yes, pre-process the forward station Station [K-1] The track map is then stored in the local map list L [n / 2 -1] If there is no track map for the next station, then L in the local map list [n / 2 -1] The track map is empty;
[0053] Step 105: Determine the station where the train is located based on the station number on the original map. [K] Is there a rear station? If yes, pre-process the rear station Station [K+1] The track map is then stored in the local map list L [n / 2+1] If there is no track map for the following station, then L in the local map list [n / 2+1] The track map is empty;
[0054] refer to Figure 3 , which explains the method of dynamically managing the stored map after the train determines its running direction.
[0055] Step 106, dynamically update the map according to the train running direction. If the train is running in the forward direction, the train location is determined by Station [K] Enter Station [K+1] If the station is running in the station direction, the rear station Station is read from the power-off protection area. [K+2] The original map file of the station is pre-processed, and then the process goes to step 107; if the train runs in the reverse direction, the train positioning is determined by the Station [K] Station Enter Station[K-1] Station, then read the previous station Station from the power-off protection area [K-2] The original map file of the station is pre-processed, and then enters step 108;
[0056] Step 107, since the train is at Station [K+1] Station, then clear Station [K+1] Station location local map list L [n / 2+1] The map in the local map list of the next stop, that is, clear the local map list L [((n / 2+1)+1)％n] The orbit map stored at [K+2] Station track maps are stored in the local map list L [((n / 2+1)+1)％n] Place.
[0057] For example, when m=3, ((n / 2+1)+1)％n =0; when N=5, ((n / 2+1)+1)％n =4, the purpose is to find the local map list L [n / 2+1] The next station at L[2] is m=3. After storing 3 stations, the next position of L[0] is L[0], and the 4th station should be placed at L[0]. m=5, the next position of L[3] is L[4], and the 4th station should be placed at L[4].
[0058] Step 108, since the train is at Station [K-1] Station, then clear Station [K-1] Station location local map list L [n / 2-1] The map in the local map list of the previous station, that is, clear the local map list L [((n / 2-1)-1+n)％n] The orbit map stored at Station [K-2] Station track maps are stored in the local map list L [((n / 2-1)-1+n)％n] Place.
[0059] The purpose is to find the local map list L [n / 2-1] The previous position of L[0]; m=3, then after storing 3 stations, the previous position of L[0] is L[2]; m=5, the previous position of L[1] is L[0], and the 4th station should be placed at L[0].
[0060] Step 109, and so on, according to the current station of the train [p] The track map is located in the local map list L [q] and the direction of the train, and update the map of the next stop of the train in the local map list in advance.
[0061] Figure 4 Schematic diagram of storing local map lists for train dynamic management;
[0062] In a circular list, counterclockwise update means updating from top to bottom, and clockwise update means updating from bottom to top.
[0063] Assume that the local map list of the train can store map files of up to 3 stations, that is, n = 3, the initial position of the train is at station d, k> = 4, and the anti-power-off area stores the original maps of 30 stations in total. Therefore, the storage order of the local map list when the train is initially positioned is L [0] Storage Station [k-1] Map, L [1] Storage Station [k] Map, L [2] Storage Station [k+1] map.
[0064] If the train is running in the forward direction, the train will pass through Station [k] Run to Station [k+1] When searching for the next station in the current local map list, there is no next station [k+2] Therefore, the local map list is dynamically updated. According to step 107, the local map list is updated. [0] Storage Station [k+2] The preprocessed map.
[0065] By analogy, the train is station [k+1] Run to Station [k+2] When searching for the next station in the current local map list, there is no next station [k+3] Therefore, the local map list is updated counterclockwise. According to step 107, the L of the local map list is updated. [1] Storage Station [k+3] The preprocessed map.
[0066] If the train runs in the reverse direction, the train will be [k] Run to Station [k-1] When searching for the next station in the current local map list, there is no next station [k-2] Therefore, the local map list is dynamically updated. According to step 108, the local map list is updated. [2] Storage Station [k-2] The preprocessed map.
[0067] By analogy, the train is station [k-1] Run to Station [k-2] When searching for the next station in the current local map list, there is no next station [k-3]Therefore, the local map list is updated clockwise. According to step 108, the L of the local map list is updated. [1] Storage Station [k+3] The preprocessed map.
[0068] Compared with the prior art, the present invention has the following beneficial effects (advantages):
[0069] 1. The initial position of the train is determined only by the longitude and latitude of the starting and ending points between stations. There is no need to pre-process the track maps of all stations before starting positioning, which greatly saves the time required for the initial positioning of the train and improves the availability of the train positioning system.
[0070] 2. Pre-process the track map of the next station of the train according to the train running trajectory, saving software running time and improving the stability of the positioning system.
[0071] 3. A method of dynamically storing maps is defined, which only stores the track maps of the previous station, current station and next station in the direction of the train's operation, saving software memory space, greatly reducing the software's dependence on platform memory, and also improving the real-time performance of the positioning system in managing maps.
[0072] It should be noted that, in the embodiments of the present invention, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.
[0073] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0074] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.
Claims
1. A dynamic management method for a train track map, characterized in that: Determine the initial current station where the train is located according to the longitude and latitude of the initial position of the train and the longitude and latitude of the starting and ending points of each station, obtain the track map of the initial current station, the station in front of the initial current station and the station behind the initial current station, and store it in the local memory of the train; after the train determines the running direction, obtain the track map of the station behind the station that the train is about to arrive at in advance according to the running direction of the train in real time, and store it in the local memory of the train; The method for determining the initial current station where the train is located includes: Traverse the original map of each station and determine that the longitude and latitude of the train's initial position point P is within the range of the longitude and latitude of the starting and ending points of a certain station K; Simplify the track of station K into a line segment AB with starting point A and end point B, calculate the perpendicular point Q from the train's initial position point P to the line segment AB, and if point Q is on the line segment AB, then station K is determined to be the initial current station of the train; When the train is running forward, the local map list is updated in a counterclockwise direction in a sequence from top to bottom; when the train is running reversely, the local map list is updated in a clockwise direction in a sequence from bottom to top; storing the initial track map of the current station in the middle position of the local map list; The track map of the station ahead of the initial current station and the track map of the station behind the initial current station are respectively stored in adjacent positions of the track map of the initial current station in the local map list; If there is no station ahead of the current station or station behind the current station, the corresponding position in the local map list is empty; The obtained track map of the rear station of the rear station is stored in a blank position in the local map list; If there is no blank position in the local map list, the track map of the station farthest from the current station in the reverse direction of the train running stored in the local memory of the train is updated to the track map of the rear station of the rear station just obtained.
2. The dynamic management method of the train track map according to claim 1, characterized in that: A local map list is constructed in the local memory of the train for storing the track map; the local map list can store the track maps of m stations, where m≥3, and m is an odd number.
3. The dynamic management method of the train track map according to claim 2, characterized in that: The local map list is a circular list.
4. The dynamic management method of the train track map according to claim 1, characterized in that: The original map of each station is pre-obtained and stored in the local memory of the train.
5. The dynamic management method of the train track map according to claim 4, characterized in that: The original map is stored in the power-off protection area of the local memory of the train.
6. The dynamic management method of the train track map according to claim 4, characterized in that: According to the station number on the original map, determine whether the train's initial current station has a front station and a rear station.
7. The dynamic management method of the train track map according to claim 4, characterized in that: The method for obtaining the track map comprises: obtaining the straight track and the curved track of the station from the original map, calculating the direction vector of the straight track, and calculating the center and diameter of the curved track.
8. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.
9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the method according to any one of claims 1 to 7 is implemented.