Method and data processing system for generating map data of a digital map

Abstract

In a method for generating map data of a digital map from raw data of the digital map with improved flexibility, an object-specific correction data set is used for generating the map data. The object-specific correction data set comprises precisely one value of a derived attribute for the map object, wherein the value of the derived attribute contained in the correction data set is allocated to the map object of the map data.

Claims

1. A method for generating of a digital map from raw data, the raw data comprising a map object and a value of a raw data attribute associated with the map object and characterizing an attribute of the map object, the digital map comprising map data that includes the map object and a value of a derived attribute associated with the map object and characterizing a different attribute of the map object, the map object comprising one of: a link and a node of the digital map, the method comprising the acts of: generating the map data by applying a global set of rules, including at least one association rule that assigns a first value of the derived attribute; applying an object-specific correction data record, that includes, for the map object, a second value of the derived attribute; and assigning the second value of the derived attribute from the correction data record to the map object of the map data, so as to generate the digital map, wherein the raw data and map data are each computer data objects stored in at least one memory accessible by a map compiler.

2. The method as of claim 1, wherein the map data includes a descriptor associated with the map object, and wherein the correction data record includes the descriptor.

3. The method of claim 1, further comprising: receiving a use data record from a user of the map data in a motor vehicle, wherein the use data record comprises a descriptor of the map object and at least one movement parameter describing a movement of the user relative to the map object; and creating or updating the correction data record based on the received use data record.

4. The method of claim 2, further comprising: receiving a use data record from a user of the map data in a motor vehicle, wherein the use data record comprises a descriptor of the map object and at least one movement parameter describing a movement of the user relative to the map object; and creating or updating the correction data record based on the received use data record.

5. A system for generating a digital map from raw data, wherein the digital map comprises map data, the system comprising: at least one memory that stores: raw data that includes a map object and a value of a raw data attribute associated with the map object and characterizing an attribute of the map object, and map data that includes the map object and a value of a derived attribute associated with the map object and characterizing a different attribute of the map object, wherein the map object comprises one of: a link and a node of the digital map; and a data processing installation configured to: generate the map data by applying a global set of rules, including at least one association rule that assigns a first value of the derived attribute to the raw data, apply an object-specific correction data record that includes, for the map object, a second value of the derived attribute, and assign the second value of the derived attribute from the correction data record to the map object of the map data, so as to generate the digital map.

6. The of claim 5, wherein the map data includes a descriptor associated with the map object, and wherein the correction data record includes the descriptor.

7. The of claim 5, further comprising: a data evaluation module configured to: receive a use data record from a user of the map data in a motor vehicle, wherein the use data record comprises a descriptor of the map object and at least one movement parameter describing a movement of the user relative to the map object, and create or update the correction data record based on the received use data record.

8. The of claim 6, further comprising: a data evaluation module configured to: receive a use data record from a user of the map data in a motor vehicle, wherein the use data record comprises a descriptor of the map object and at least one movement parameter describing a movement of the user relative to the map object, and create or update the correction data record based on the received use data record.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 shows an embodiment of a data processing installation using a schematic depiction.

DETAILED DESCRIPTION OF THE DRAWING

(2) It is pointed out that the depicted FIGURE and the associated description are merely an exemplary embodiment of the invention. In particular, depictions of combinations of features in the FIGURE and/or the description of the FIGURE are not intended to be interpreted to mean that the invention necessarily requires implementation of all the cited features. Other embodiments of the invention can contain fewer, more and/or different features. The scope of protection and the disclosure of the invention result from the accompanying patent claims and the complete description. It is also pointed out that the depiction is a basic depiction of an embodiment of the invention. The arrangement of the individual depicted elements relative to one another is chosen only by way of example and can be chosen differently for other embodiments of the invention.

(3) FIG. 1 shows a data processing installation 5, which can also be referred to as a compiler 5 or map compiler 5. A data memory 1 stores raw data 1 of the digital map. A further data memory 2 is used to store the map data 2 of the digital map. The data memories 1, 2 can each be part of the data processing installation 5. They can alternatively be configured as separate units or as parts of other data processing units, which are not depicted in FIG. 1. The data memories 1, 2 can be different memory areas of the same physical memory (e.g. of a hard disk of the data processing installation 5). To generate the map data 2, the map compiler 5 accesses a global set of rules 3 and a correction data record 4.

(4) The example below is intended to clarify the sequence of events in the method according to the invention.

(5) Table I below depicts exemplary raw data 1:

(6) TABLE-US-00001 TABLE I Raw data 1 Link ID CA MD SL R0815 1 1 130 R0816 1 0 80 R0817 0 1 80 R0818 0 0 100

(7) The raw data 1 comprise four map objects that have the descriptors indicated in the first column (with the heading “Link ID”). At this juncture, it should be pointed out that the descriptor of a map object can be changed or reallocated during compilation of the digital map. This will become clear below on the basis of the exemplary embodiment. The four map objects are “links”, that is to say sections of roads.

(8) The raw data 1 further comprise the attributes CA, MD and SL indicated in the further columns. Each of these attributes has an associated value for each map object.

(9) The attribute CA (for “control access”) relates to the property of whether access to this link is restricted, that is to say for example is permissible only for motor vehicles but not for cyclists or pedestrians. By way of example, an object having the value CA=0 can have no access restriction, whereas there is an access restriction for CA=1.

(10) The attribute MD (for “multiply digitized”) relates to the property of whether the link has two directions of travel. By way of example, the directions of travel can exist as separate links (having separate descriptors) in the case of directions of travel that are physically separate (e.g. as a result of a median strip and/or a crash barrier). In this case, MD=1, for example. By contrast, a link can comprise two directions of travel. In that case MD=0.

(11) The attribute SL (for “speed limit”) relates to the maximum permissible speed. For example, SL=80 can mean that the maximum permissible speed is 80 km/h.

(12) Table II shows an example of a global set of rules 3.

(13) TABLE-US-00002 TABLE II Global set of rules 3 CA MD SL AA1 1 1 130 2 1 0 80 1 0 1 80 1 0 0 100 0

(14) The set of rules 3 contains four association rules in total that each correspond to a row of table II. The association rules assign a value of the derived attribute AA1 on the basis of the values of the attributes CA, MD and SL. It should be noted that the simplified depiction in table II was chosen from didactic points of view. Global sets of rules that are actually used can be much more extensive. Moreover, the association rules can be more complex. By way of example, the association rules can relate not only to exact values (e.g. SL=80) but also to ranges of values (e.g. 80<SL<120).

(15) The derived attribute AA1 can relate to the road type, for example. As such, AA1=2 can correspond to the road type “freeway”. According to the association rule stored in the first row of table II, this value is allocated if a link has restricted access (CA=1) and is separated according to the direction of travel (MD=1) and also has a maximum speed of 130 km/h. A value AA1=1 could correspond to a road type “road similar to a freeway”. A value AA1=0 could correspond to a road type “country road”.

(16) The global set of rules 2 is used to assign the values of the derived attribute AA1 to the map objects during compilation, that is to say generation of the map data 2 from the raw data 1.

(17) Table III shows a correction data record 4. The correction data record 4 is used to assign values of the derived attribute AA1 to individual map objects that are denoted on the basis of their descriptor (Link ID) set out in the left-hand column. It should again be pointed out that during compilation of the digital map it is possible for new descriptors to be allocated for the map objects. The Link IDs in Table III are thus not in agreement with the Link IDs in Table I.

(18) TABLE-US-00003 TABLE III Correction data record 4 Link ID AA1 4711 1 4712 1 4713 0

(19) As is evident from Table III, the value AA1=1 of the derived attribute AA1 is assigned to the map object having the descriptor “4711”. It is unimportant in this case which value of the derived attribute AA1 has actually been assigned to the object “4711” on the basis of the global set of rules 3. By way of example, the link “4711” can be a road similar to a freeway (AA1=1) but having atypical properties, meaning that it would be incorrectly classified as a freeway (AA1=2) on application of the global set of rules 3.

(20) Further, the map object having the descriptor “4712” is assigned the value AA1=1 of the derived attribute AA1, and the map object having the descriptor “4713” is assigned the value AA1=0.

(21) Examples of derived attributes that can be assigned by means of the method according to the invention are the road type and/or the presence of a physical separation for the directions of travel (e.g. median strip and/or crash barrier). A further example relates to the likelihood of road users in the surroundings being reliable. This derived attribute can be important for driver assistance systems of motor vehicles that allow semiautomated, highly automated or fully automated driving of the motor vehicle. Other motor vehicles can be classified as reliable road users, for example, whereas cyclists and pedestrians are classified as unreliable road users. Further levels are also conceivable. As such, children could be classified as particularly unreliable, for example. An applicable derived attribute AA2 conveying the likelihood of road users in the surroundings being reliable could be AA2=100% on a freeway and AA2=0% close to a kindergarten or a school, for example.

(22) The example of this derived attribute AA2 will be used below to explain the way in which the data evaluation module 6 works. In FIG. 1, the connection from the map data 2 to the data evaluation module 6 is depicted in dashes. This depiction is intended to clarify that for example data from the data memory 2 cannot be transmitted to the data evaluation module 6. Rather, use data records from users of the map data 2, in particular from motor vehicles, are transmitted to the data evaluation module 6. The use data records comprise a descriptor of a map object and at least one movement parameter describing a movement of the user relative to the map object.

(23) It should be assumed by way of example that a particular link having the Link ID “6210” has the attribute AA1=0, that is to say that it is a country road. For this link, a value AA2=80% is allocated on the basis of the global set of rules 3. There is thus a very high likelihood of 80% that the road users in this road section are reliable.

(24) The Link 6210 further has the attribute SL=100, that is to say that a maximum speed of 100 km/h applies. Numerous vehicles passing through the road section 6210 use a mobile data connection to report their driving data to a central server (what is known as a “backend”), where the data are processed. The central server can be the data evaluation module 6. Similarly, the use data records can be transmitted from the server to the data evaluation module 6 in unprocessed or processed form.

(25) One of the movement parameters relates to the actual instantaneous speed. When evaluating the numerous use data records by means of a machine learning method suitable for detecting recurring patterns in the data, the data evaluation module 6 makes the following discovery. The instantaneous speed of the vehicles traveling on the Link 6210 is approximately 100 km/h for a continuous period of 28 minutes in each case. For a subsequent period of approximately 2 minutes in each case, the instantaneous speed is then only 20 km/h, on average, however. At the same time, the statistical variation (or variance) in the instantaneous speed increases. The end of the approximately two-minute period is followed by the described period of approximately 28 minutes again. From this observation, it can be concluded that the Link 6210 has a bus stop that is called at half-hourly.

(26) On the basis of the use data records evaluated in this manner, the correction data record 4 can now be created as follows. Since there is a substantially greater likelihood of pedestrians being present at a bus stop than on an open country road, the value AA2=20% is assigned for the Link 6210 in the correction data record 4. Further, the correction data record 4 could be used to assign the value 1 to an attribute denoting the presence of a bus stop.

LIST OF REFERENCE SIGNS

(27) 1 Raw data of the digital map 2 Map data 3 Global set of rules 4 Correction data record 5 Data processing installation (compiler) 6 Data evaluation module

(28) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.