METHOD OF CREATING MAP DATA COMPRISING TRANSIT TIMES FOR INTERSECTIONS

• US 20110112760A1
• Filed: 10/12/2009
• Published: 05/12/2011
• Est. Priority Date: 12/03/2008
• Status: Active Grant

• Current Assignee: Tomtom Global Content B.V (TomTom NV)
• Original Assignee: Tomtom Global Content B.V (TomTom NV)
• Inventors: Serbanescu, Alexandru, Hiestermann, Volker
• Granted Patent: US 9,235,993 B2
• Time in Patent Office: Days
• US Class Current: 701/204
• CPC Class Codes: G01C 21/32 Structuring or formatting of map data
• CPC Class Codes: G01C 21/34 Route searching; Route guidance
• CPC Class Codes: G01C 21/3461 Preferred or disfavoured areas, e.g. dangerous zones, toll or emission zones, intersections, manoeuvre types, segments such as motorways, toll roads, ferries
• CPC Class Codes: G01C 21/3841 Data obtained from two or more sources, e.g. probe vehicles
• CPC Class Codes: G01C 21/3844 Data obtained from position sensors only, e.g. from inertial navigation
• CPC Class Codes: G09B 29/106 using electronic means

Abstract

A computerised method is disclosed of creating map data from position data derived from the positions of at least one vehicle over a period of time, the map data including a plurality of navigable segments representing segments of a navigable route in the area covered by the map and the map data also including intersections between navigable segments representing intersections in the navigable route. In at least one embodiment, the method includes using a processing circuitry to perform the following: i. processing the position data; ii. calculating from the processing of the position data a transit time or set of transit times for at least some of the intersections in the map data; and iii generating further map data, which for at least some of the intersections therein, contains the calculated transit time or set of transit times associated with the intersection for which the calculation was made.

Claims

1. A computerised method of creating map data from position data derived from the positions of at least one vehicle over a period of time, the map data comprising a plurality of navigable segments representing segments of a navigable route in the area covered by the map and the map data also comprising intersections between navigable segments representing intersections in the navigable route, the method comprising using a processing circuitry to perform the following:

i. processing the position data;

ii. calculating from the processing of the position data a transit time or set of transit times for at least some of the intersections in the map data; and

iii. generating further map data, which for at least some of the intersections therein, contains the calculated transit time or set of transit times associated with the intersection for which the calculation was made.

2. A method according to claim 1 in which a classification scheme related to intersections within the map data is generated and further in which the results of the processing of the position data is stored within the classification scheme.

3. A method according to claim 2 in which the classification scheme comprises at least one of:

a route through the intersection;

class, type or importance of the road segments at the intersection (incoming and/or outgoing);

angle of road segments at intersection;

presence of traffic lights;

difference in driving speeds between the outgoing and incoming segments;

the speed ranges within the incoming; and

outgoing road segments.

4. A method according to claim 1 in which the position data is analysed to determine position data corresponding to a portion of a vehicle trip that passed through an intersection and wherein such determination may be made by determining whether vehicle positions within the position data are within at least one of the following:

a predetermined distance of the intersection;

a predetermined time of the intersection;

a predefined class of vehicle categories; and

a predefined travel direction or heading.

5. A method according to claim 4 in which data that has been determined to relate to a portion of a vehicle trip that passed through an intersection is analysed to determine the time taken for the vehicle to pass through the intersection and may be further analysed to determine one or more of the following:

the time taken to approach the intersection in a pre-intersection zone;

the time take in the intersection in an inter-intersection zone; and

the time taken after the intersection in a post intersection zone.

6. A method according to claim 4 in which data is averaged for anyone intersection and in which the data may be averaged within predetermined time periods which may be of a predetermined length.

7. A method according to claim 6 in which the averaged times are analysed to determine whether the data that created the average met a predetermined quality criteria and which may apply a further classification scheme if the averaged times do not meet this predetermined quality criteria.

8. A method according to claim 1 in which a set of equations is determined from vehicle trip data within the position data, may be in which known parameters of the equations are journey times for road segments and in which unknown parameters are transit times for intersections.

9. A method according to claim 8 in which an approximate solution to the equations is determined using a mathematical approximation which includes minimising the error using a least squares solution.

11. Map data comprising a plurality of navigable segments, representing segments of a navigable route in the area covered by the map, and intersections, representing intersections between the navigable segments covered by the map wherein at least some of the intersections have a transit time or set of transit times associated therewith that has been derived by averaging position data using the method of claim 1.

13. A non-transitory machine readable medium containing

instructions which when read by a machine cause that machine to perform the method of claim 1.

15. A non-transitory machine readable medium containing the map data of claim 11.

10. A machine arranged to create map data comprising a plurality of navigable segments, representing segments of a navigable route in the area covered by the map, and intersections, representing intersections between the navigable segments covered by the map, the machine comprising processing circuitry arranged to process position data derived from the positions of at least one vehicle over a period of time, the processing circuitry being programmed to:

i. process the position data;

ii. calculate from the processing of the position data a transit time or set of transit times for at least some of the intersections in the map data; and

iii. generate further map data, which for at least some of the intersections therein, contains the calculated transit time or set of transit times associated with the intersection for which the calculation was made.

14. A non-transitory machine readable medium containing instructions which when read by a machine cause that machine to perform as the machine of claim 10.

12. A set of map parameters that in correlation with map data comprising a plurality of navigable segments, representing segments of a navigable route in the area covered by the map, and intersections, representing intersections between the navigable segments covered by the map that would allow an optimised estimation of the transit times based on clustering (or type of intersection).