Method, control device, computer program and machine-readable storage medium for creating a digital map

Abstract

A method for creating a digital map by a control device, the method comprising: receiving measurement data of at least one sensor of at least one mapping vehicle; determining a position and an orientation of the mapping vehicle by a SLAM method from the received measurement data; generating the digital map based on the received measurement data and the position and the orientation of the mapping vehicle; receiving, from a database or determining by the position of the mapping vehicle, data of at least one road route; dividing the digital map into at least two map segments, the map segments constituting at least a part of the digital map, wherein the map segments are created along the road route, wherein the map segments have connection information to each other corresponding to the road route. The invention also relates to a control device, a computer program and a machine-readable storage medium.

Description

TECHNICAL FIELD

[0001] The invention relates to a method for creating a digital map, a control device, a computer program and a machine-readable storage medium. BACKGROUND

[0002] Automated driving functions and vehicles with automated driving functions are becoming increasingly important. Up-to-date and precise maps are necessary for successful implementation of automated driving functions.

[0003] By using a digital map for automated driving functions, the limited sensor range of action and coverage of the scanning area of the vehicle sensors can be compensated for and complete environmental perception can be achieved.

[0004] Furthermore, the digital map can be created outside the vehicle's surroundings with generally higher computing performance, whereby more complex processing algorithms and larger data quantities can be processed and provided. The utilization of the map by the control device on the vehicle side requires less computing performance compared to the creation of the map outside the vehicle.

[0005] In order to utilize the digital map in automated driving functions, the digital map is usually divided into smaller map tiles (Kartenkacheln). Here, the digital map is divided into a grid with identical map tiles. The problem with this division of the digital map lies in the uncontrolled course of the borders of the map tiles. As a result, road courses (Straβenverlauf) can be separated at unsuitable locations, for example at intersections, so that multiple map tiles are required for navigation of this type. The computing overhead and the required data quantity when updating, using and calling the digital map are thus increased. SUMMARY

[0006] The task on which the invention is based can be seen as proposing a method for such a partitioning of a digital map which reduces the computing overhead and the data quantity to be processed when handling the digital map.

[0007] The task is solved by means of a method for creating a digital map, a control device, a computer program and a machine-readable storage medium according to the invention.

[0008] According to an aspect of the invention, a method for creating a digital map is provided. The method can be executed by a control device.

[0009] In one step, at least one sensor measurement data of at least one mapping vehicle (Kartierungsfahrzeuge) is received.

[0010] On the basis of the received measurement data, the position and orientation of the mapping vehicle are determined by means of a SLAM method. The mapping can be carried out, for example, by means of a Graph-SLAM method, which is set up to explicitly model the vehicle position and the vehicle orientation.

[0011] The measurement data received from the mapping vehicle can be pre-processed. Next, the measurement data received from different mapping vehicles are geometrically oriented. This orientation can be carried out by means of static landmarks and features, which can be found in different sets of measurement data by means of the control device. After the measurement data have been oriented by means of the control device, the positions of the static landmarks and the poses of the mapping vehicles can be determined. Here, the pose of the mapping vehicle comprises the position and the orientation of the mapping vehicle during different points in time.

[0012] On the basis of the received measurement data, the position and orientation of the mapping vehicle are determined by means of a SLAM method. The mapping can be carried out, for example, by means of a Graph-SLAM method, which is set up to explicitly model the vehicle position and the vehicle orientation.

[0013] On the basis of the received measurement data, the position and orientation of the mapping vehicle are determined by means of a SLAM method. The mapping can be carried out, for example, by means of a Graph-SLAM method, which is set up to explicitly model the vehicle position and the vehicle orientation.

[0014] Alternatively or additionally, the data of the road route can be received from a database. This database can be a database integrated in the control device or an external database which can be accessed by the control device in a data-conveying manner.

[0015] In a further step, the digital map is divided into at least two map sections, which constitute at least a part of the digital map. By dividing the digital map into a plurality of map sections, the amount of data to be received and processed can be reduced.

[0016] According to the application, map sections are created along the road route, wherein the map sections have connection information to one another which corresponds to the road route.

[0017] Preferably, the connection information of the map sections can correspond to the course of the lanes of the road route, so that, for example, map sections which map an intersection and map sections which map a tunnel can be clearly distinguished from one another.

[0018] By dividing the digital map into map sections which follow the geometric course of the road, the best possible initial mapping can be carried out. The boundaries of the map sections do not necessarily have to extend along straight lines. Two adjacent map sections can thus be arranged in such a way that the segmentation of the road is minimized by the number of map sections used.

[0019] By this method, for example, it can be avoided that the border of a map section crosses an intersection of the road route or extends along the road center.

[0020] Furthermore, the borders of all map sections are known and created based on the structure of the road route. This unambiguous handling of the map sections enables an exact and consistent orientation of the map sections. Furthermore, ambiguities in the creation of map sections extending over multiple height layers, such as parking garages, overpasses and underground passages, can be avoided, since the connection information of the map sections enables the association along the different height layers.

[0021] When performing an update, the number of map sections required can be minimized. Since all map sections having a road route must be updated and adverse zoning of the road route in the longitudinal direction is prohibited, the amount of data required can be reduced and the update process is performed particularly quickly. Similarly, for this the amount of data used by a vehicle obtaining map sections from the control device for a navigation task can be reduced. Adjacent map sections which are implemented without a road route do not need to be and thus are not transmitted.

[0022] The control device can provide the map sections of the digital map to a requesting vehicle via a communication connection. The communication connection can be based on WLAN, UMTS, GSM, LTE, 5G and similar transmission standards, for example.

[0023] In an advantageous configuration, different map sections can be created and provided for different driving directions along the road route. Thereby, adverse orientation and occlusion of features in the mapping process can be avoided. In particular, features which are only visible from one direction can be stored and provided purposefully in the respective direction-dependent map section.

[0024] According to another aspect of the application, a control device is provided, wherein the control device is set up to implement the method. The control device can be a vehicle-side control device, a control device external to the vehicle, or a server unit external to the vehicle, for example a cloud system.

[0025] Furthermore, according to one aspect of the application, a computer program is provided, which comprises instructions which, when the computer program is implemented by a computer or control device, cause the computer or control device to implement the method according to the application. According to another aspect of the application, a machine-readable storage medium is provided, on which the computer program according to the application is stored.

[0026] ​According to the BASt (Bundesanstalt für Straβenwesen) standard, a vehicle can be capable of assisted, partially automated, highly automated and / or fully automated or driverless operation.

[0027] The vehicle can be, for example, a passenger car, a heavy goods vehicle, an autonomous taxi and the like. The vehicle is not limited to operation on a road. Rather, the vehicle can also be configured as a watercraft, an air vehicle, for example a transport drone, and the like.

[0028] The map section preferably has connection information to its neighboring map sections. The connection information can map drivable paths or drivable road routes leading from one map section to a neighboring map section.

[0029] The connection information thus represents a road route through the map section.

[0030] The connection information can thus be used technically expediently and quickly to find the horizon of the potentially reachable map sections from a certain position in the road network. The connection information can thus also be used by a mapping algorithm for determining the map sections required for planning a trajectory. An additional search algorithm can thus be dispensed with.

[0031] According to an embodiment, map sections having the same or different shape, size, position in the digital map and / or angular orientation to one another are created, wherein the map sections are configured next to one another and / or overlapping one another. The map sections can in particular overlap locally or completely and thus, for example, two different planes are configured which can be called up depending on the driving direction or the planning direction.

[0032] Unlike a regular map grid with map tiles, the map sections can in particular have different sizes, shapes, areas, orientations and the like. Furthermore, it is not necessary for the total area of the digital map to be covered by at least two map sections, thereby reducing the storage requirement for the received map sections.

[0033] The map sections map a limited area of the digital map, or rather the map sections are configured as a digital map portion having a limited area. Here, the map sections contain the map information of the digital map depending on the arrangement of the map sections on the digital map.

[0034] The plurality of map sections can be stacked on top of one another, next to one another or spaced apart from one another.

[0035] Stacked structure or an undershooting (Unterschneidung) or by means of a tunnel in the road route, examples of the use of overlapping or superimposed map sections can be illustrated. By means of a plurality of superimposed map sections it is likewise possible to digitally reproduce a parking garage with a plurality of levels. By means of the connection information it is possible to precisely implement the connecting ramps of the levels of the parking garage.

[0036] By means of the use of a plurality of overlapping or superimposed map sections it is also possible to unambiguously digitally map complex traffic situations and road routes which span a plurality of height levels and to use them for the purpose of a navigation task.

[0037] The connection information of the map sections can differ from one another and it is not necessary to necessarily interrelate two or more map sections with one another.

[0038] The connection information preferably gives an indication of how the road route of the first map section continues outside the first map section.

[0039] The road route of the first map section can, for example, lead to a second map section and can lead to a parallel third map section by means of a branching-off of the road route. The connection information of this first map section can therefore have an association to the second and third map sections.

[0040] According to another embodiment, map sections are created which have a center point, wherein the center point of the map section is constructed along the road route. By means of this measure it is possible to create the map sections centrally along the road route and to orient the map sections centrally along the road route. The center line of the road route preferably constitutes a parameter for centering the map sections. By means of this, each map section can comprise as large a portion of the road route as possible, thereby reducing the number of map sections required.

[0041] According to another embodiment, map sections are created which have geographical coordinates which define the boundaries of the map sections. For example, the geographical coordinates of the corner points or intermediate points of the boundaries which define the map sections can be stored together with the local map information of the respective map section. For this purpose, one file or one file section of the digital map can be used for each map section.

[0042] The geographical coordinates can, for example, be configured as longitude and latitude.

[0043] By means of the precise course of the boundaries of the map sections it is technically simple to ascertain whether a vehicle is within a map section or has left the map section.

[0044] The geographical coordinates are not restricted to the use of map sections which are configured in the form of rectangles or squares. Map sections which are configured in the form of triangles, regular polygons and / or irregular polygons are also possible. In digital maps it is possible, in particular, to use map sections of different configurations.

[0045] Preferably, the shape or size, for example the area, of the plurality or the individual map segments can match the shape of the road route.

[0046] In another embodiment, at least one trajectory and / or width of the road route through the at least one map segment is stored in the respective map segment. By this measure, important properties and the shape of the road route can be stored in the respective map segment.

[0047] By the assignment to the map segments, the boundaries of the map segments enable a coarse positioning of the vehicle on the digital map. By the information and properties of the road route of the map segments, a more accurate positioning of the vehicle on the road or lane of the road route can be enabled.

[0048] According to another embodiment, at least one driving direction and / or the number of lanes of the road route through the at least one map segment is stored in the respective map segment. For example, a set of map segments can be created for each lane in order to enable a direction-dependent mapping of landmarks.

[0049] Thus, the provision of connection information for the opposite direction can be dispensed with. By this method, in particular, the positioning algorithm can be used effectively and without errors, since an incorrect lane assignment is excluded in the map segments created in relation to the driving direction.

[0050] According to another embodiment, the connection information of the map segments is stored in the respective map segment depending on the road route and at least one driving direction along the road route.

[0051] In another configuration, at least one map segment is created depending on one driving direction along the road route.

[0052] Thereby, the map segments and the respective connection information can be created unidirectionally or depending on the respective driving direction along the road route. Thereby, the scanning range of the sensors used for the mapping can be used optimally.

[0053] Preferably, thus, only the map segments in the driving direction in front of the vehicle making the request can be called up for navigation. Preferably, the map sections that can be reached by continuing to drive along the road route can be preloaded.

[0054] According to another embodiment, at least two map segments with stored meta-information are created. By this measure, additional information can be assigned to the map segments. The map segments are often in a state of update, whereby it is advantageous to store additional information in addition to the so-called Graphmap-Ebene. The meta-information can have, for example, the date of creation, the date of update, information about the creation algorithm, creation parameters, etc. BRIEF DESCRIPTION OF DRAWINGS

[0055] The preferred embodiments of the application are explained in detail below on the basis of highly simplified schematic illustrations.

[0056] Herein is shown:

[0057] Figure 1 A schematic illustration of a vehicle arrangement for illustrating the method is shown;

[0058] Figure 2 A schematic illustration of a digital map is shown;

[0059] Figure 3 A perspective view of a road route is shown to illustrate the creation of a map section;

[0060] Figure 4 A top view of another road route is shown to illustrate the creation of a map section; and

[0061] Figure 5 A schematic flow chart for illustrating the method according to an embodiment is shown. DETAILED DESCRIPTION

[0062] Figure 1 A schematic illustration of a vehicle arrangement 1 for illustrating the method 2 is shown. The vehicle arrangement 1 has one or more mapping vehicles 4.

[0063] The mapping vehicle 4 can for example be a passenger car equipped with a sensor device for the detection of the surroundings.

[0064] The mapping vehicle 4 has a sensor 6 for collecting measurement data of the surroundings U.

[0065] The sensor 6 can be configured as a laser radar sensor, a radar sensor, a camera sensor, etc.

[0066] The measurement data can be collected by a computing unit 8 on the vehicle side and transmitted to a control device 12 outside the vehicle via a communication connection 10.

[0067] The communication connection 10 can for example be based on WLAN, UMTS, GSM, 4G, 5G and similar transmission standards.

[0068] The control device 12 is configured as a server unit outside the vehicle and can receive the measurement data of the mapping vehicle 4 and use the measurement data for the creation of a digital map.

[0069] The control device 12 can create and authenticate the digital map by a plurality of mapping steps, in order to provide the digital map to the vehicle 14 or to the other road users via the further communication connection 11 for implementing the automated driving function. In the creation of the digital map, the entire digital map or a part of the digital map is divided into map sections.

[0070] Here, the control device 12 can provide the created digital map with the mapping sections to the other road users 14. In order to keep the amount of data to be transmitted and to be processed by the road users 14 small, the map information of the digital map is provided in the form of map sections which are geographically relevant to the road users 14.

[0071] Figure 2 A schematic illustration of the digital map 16 is shown, which is created and / or updated by the control device 12 by evaluation analysis and processing of the measurement data.

[0072] The digital map 16 has a road route 18. The road route 18 is composed of a highway 20 and a fork or T-junction 21 leading to a branch 22, by way of example.

[0073] The area of the digital map 16 along the road route 18 is divided by a plurality of map sections cl to c5. Here, the map sections c are arranged in such a way that the road route 18 is completely covered by as few map sections c as possible. Here, the number of partitions or boundaries 24 of the map sections c is minimized in order to avoid deviations and approximation errors at the edge.

[0074] In the shown embodiment, the road route 18 is roughly mapped by three large-area map sections cl, c3, c4. In addition, further map sections c2, c5 are constructed, which contain the details of the fork 21 leading to the branch 22 and of an exit 26 to the branch as map information.

[0075] The map sections c have different sizes and shapes in order to enable an optimal coverage of the shown road route 18.

[0076] In addition to the section with the map information and the road route 18, the map sections c also have connection information 28 or connection data.

[0077] The connection information 28 shows how the road route 18 extends through the respective map section c. The connection information 28 describes, in particular, that the road route 18 extends across a plurality of map sections c. Here, the map sections c are partly or completely superimposed.

[0078] The highway 20 of the road route 18 extends from a first map section cl through a second map section c2 to a fourth map section c3.

[0079] The branch 22 mapped by the third map segment c3 can be reached via the bifurcation 26 mapped by the fifth map segment c5 or via the T-junction 21 or else via the second map segment c2.

[0080] In Figure 3 A perspective view of the road route 18 is shown in order to illustrate the creation of the map segments c. For the sake of clarity, the boundaries 24 of the created map segments c are shown as circles, which delimit the road route 18.

[0081] The road route 18 is shown in a state divided by different map segments c in order to illustrate the division of the road route 18 even in multiple height layers H.

[0082] Here, the division of the road route 18 by the map segments c differs depending on the driving direction. The road route 18 is configured as a motorway 30 and has two entries or exits 31. The entries 31 are connected to an underground tunnel 32, which extends below the motorway 30, for example. The respective map segments c can be related to one another by the connection information 28 independently of the height layer H.

[0083] By using the connection information 28, ambiguities can also be avoided when the map segments c are superimposed.

[0084] Figure 4 A top view of another road route 18 is shown in order to illustrate the creation of the map segments c. The road route 18 has a motorway 30, which enters a roundabout 34 via an exit 31 or an entry. The roundabout 34 is located in the height direction H above the motorway 30. Here, the motorway 30 extends through a tunnel 36 below the roundabout 34.

[0085] By the optimal size of the map segments c, complex road routes 18, in particular in urban areas, can also be mapped exhaustively, and precise navigation can be implemented on the basis of the created map segments c.

[0086] Figure 5 A schematic flowchart for illustrating a method 2 according to an embodiment is shown. The method 2 serves to create a digital map 16 and to divide the digital map 16 into optimal map segments c. The method 2 and the following steps can preferably be carried out by the control device 12.

[0087] In a step 40, measurement data of at least one sensor 6 of at least one mapping vehicle 4 is received.

[0088] From the received measurement data, the position and the orientation of the mapping vehicle 4 are determined by a SLAM method 41.

[0089] In a further step 42, a digital map 16 is generated on the basis of the received measurement data, the position and the orientation of the mapping vehicle 4.

[0090] In a further step 43, data of at least one road route 18 are received from a database 13 or are calculated by the position of the mapping vehicle 4. The database 13 can be, for example, a memory of the control device 12 or can be an external database 13.

[0091] Next, the digital map 16 is divided 44 into at least two map sections c, which constitute at least a part of the digital map 16. The map sections c are created along the road route 18, wherein connection information 28 to each other corresponding to the road route 18 is assigned to the map sections c by the control device 12.

[0092] In a final step 45, the digital map 16 with the map sections c and the connection information 28 is provided to other traffic participants 14 for navigation tasks and for implementing automated driving functions.

Claims

1. A method (2) for creating a digital map (16) by a control device (12), wherein: - measurement data of at least one sensor (6) of at least one mapping vehicle (4) are received; - a position and an orientation of the mapping vehicle (4) are determined by a SLAM method from the received measurement data; - the digital map (16) is generated on the basis of the received measurement data, the position and the orientation of the mapping vehicle (4); - data of the at least one road route (18) are received from a database (13) or are determined from the position of the mapping vehicle (4); - the digital map (16) is divided into at least two map sections (c), which form at least a part of the digital map (16), characterized in that the map sections (c) are created along the road route (18), wherein the map sections (c) have connection information (28) to one another which corresponds to the road route (18), wherein the connection information (28) gives an indication of how the road route (18) of a map section (c) extends through the respective map section (c) and how the road route (18) of a map section (c) extends outside the map section (c), wherein the connection information (28) enables a correlation of the map sections (c) along different height layers, wherein the connection information (28) of a map section (c) is stored in the respective map section (c) in accordance with a road route (18) and at least one driving direction along the road route (18), wherein a plurality of map sections (c) are arranged in such a way that the road route (18) is completely covered by as few map sections (c) as possible.

2. The method of claim 1, wherein, - map sections (c) are created which have the same or different shapes, sizes, positions in the digital map (16) and / or angular orientations to one another, wherein the map sections (c) are constructed next to one another and / or overlapping one another.

3. The method of claim 1 or 2, wherein, - map sections (c) are created which have a center point (M), wherein the center points (M) of at least one map section (c) are constructed along the road route (18).

4. The method of any one of claims 1 to 3, wherein, - map sections (c) are created which have geographic coordinates, which define the boundaries (24) of the map sections (c).

5. The method of any one of claims 1 to 4, wherein, - at least one track and / or a width of the road route (18) through at least one of the map sections (c) is stored in the respective map section (c).

6. The method of any one of claims 1 to 5, wherein, - at least one driving direction and / or a number of lanes of the road route (18) through at least one of the map sections (c) is stored in the respective map section (c).

7. The method of any one of claims 1 to 6, wherein, - the connection information (28) of the map sections (c) is stored in the respective map section (c) in accordance with a road route (18) and at least one driving direction along the road route (18), wherein at least one map section (c) is created in accordance with one driving direction along the road route (18).

8. The method of any one of claims 1 to 7, wherein, - at least two map sections (c) are created which have stored meta-information. - at least two map sections (c) are created which have stored meta-information.

9. A control device (12), wherein The control device (12) is arranged to implement the method according to any one of claims 1 to 8.

10. A computer program product comprising instructions which, when the computer program product is implemented by a computer or control device (12), cause the computer or control device to implement the method (2) according to any one of claims 1 to 8.

11. A machine-readable storage medium on which the computer program product according to claim 10 is stored.

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