TRAFFIC MONITORING SYSTEM AND METHOD

• US 20150192422A1
• Filed: 03/20/2015
• Published: 07/09/2015
• Est. Priority Date: 10/10/2005
• Status: Active Grant

• Current Assignee: TomTom Traffic B.V. (TomTom NV)
• Original Assignee: TomTom International BV (TomTom NV)
• Inventors: Adam, Thomas Bruce Watson, Atkinson, Ian Malcolm, Dixon, Michael Joseph
• Granted Patent: US 10,557,714 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01C 21/3492 employing speed data or traffic data, e.g. real-time or historical traffic control systems for road vehicles involving transmission of navigation instructions to the vehicle G08G1/0968
• CPC Class Codes: G08G 1/00 Traffic control systems for road vehicles arrangement of road signs or traffic signals E01F9/00 ; automatic vehicle control B62D
• CPC Class Codes: G08G 1/096827 where the route is computed onboard
• CPC Class Codes: G08G 1/096844 where the complete route is dynamically recomputed based on new data
• CPC Class Codes: G08G 1/096883 where input information is obtained using a mobile device, e.g. a mobile phone, a PDA
• CPC Class Codes: G08G 1/0969 having a display in the form of a map

Abstract

The present invention combines the geographical coverage possible with fixed, pre-defined route segment costs (e.g. the legal speed limit) with, wherever possible, richer time dependent costs. A user of, for example, a portable navigation device, can therefore continue route planning as before to virtually any destination in a country covered by the stored map database, but wherever possible, can also use traffic data with time-dependent costs, so that the effect of congestion with any time predictability can be accurately taken into account as an automatic, background process. It leaves the user to simply carry on driving, following the guidance offered by the navigation device, without needing to be concerned about congestion that exists now, and whether it will impact his journey.

Claims

1-56. -56. (canceled)

57. A traffic monitoring system comprising a processing module arranged to process data representative of vehicles moving along roads in a designated geographical area, the roads being defined in a map database in terms of route segments, to measure traffic speed or transit time data as a function of time and to:

generate a database of historical time-dependent traffic speeds or transit times for at least some route segments in the map database, the data associated with a route segment comprising an average traffic speed or transit time along the route segment for each of a plurality of time windows;

identify currently congested route segments on which the current traffic speed or transit time is less than expected; and

predict a traffic speed or transit time for a future time for at least one currently congested route segment based on a comparison of recently observed traffic speeds or transit times for the at least one segment with the historical average traffic speed or transit time for the appropriate time window, wherein said prediction comprises decaying the recently observed traffic speeds or transit times to the historical average traffic speed or transit time as the distance of the prediction into the future grows.

58. The traffic monitoring system of claim 57 in which said prediction comprises comparing the recently observed traffic speeds or transit times for the at least one segment with the historical average traffic speed or transit time for the appropriate time window, and scaling the predicted traffic speed or transit for a future time in proportion to the ratio of the recently observed traffic speeds or transit times to the historical average traffic speed or transit time for the appropriate time window.

59. The traffic monitoring system of claim 57 in which the data representative of vehicles moving along roads in a designated geographical area is derived from GPS tracks stored by GPS based navigation devices in vehicles travelling along the roads.

60. A computer-implemented method in which data representative of vehicles moving along roads in a designated geographical area, the roads being defined in a map database in terms of route segments, is processed by a processing module of a traffic monitoring system to measure traffic speed or transit time data as a function of time and to:

generate a database of historical time-dependent traffic speeds or transit times for at least some route segments in the map database, the data associated with a route segment comprising an average traffic speed or transit time along the route segment for each of a plurality of time windows;

identify currently congested route segments on which the current traffic speed or transit time is less than expected; and

predict a traffic speed or transit time for a future time for at least one currently congested route segment based on a comparison of recently observed traffic speeds or transit times for the at least one segment with the historical average traffic speed or transit time for the appropriate time window, wherein said prediction comprises decaying the recently observed traffic speeds or transit times to the historical average traffic speed or transit time as the distance of the prediction into the future grows.

61. The method of claim 60 in which said prediction comprises comparing the recently observed traffic speeds or transit times for the at least one segment with the historical average traffic speed or transit time for the appropriate time window, and scaling the predicted traffic speed or transit for a future time in proportion to the ratio of the recently observed traffic speeds or transit times to the historical average traffic speed or transit time for the appropriate time window.

62. The method of claim 60 in which the data representative of vehicles moving along roads in a designated geographical area is derived from GPS tracks stored by GPS based navigation devices in vehicles travelling along the roads.

63. A non-transitory computer-readable medium storing computer software that, when executed on a computer, causes the computer to perform the method of claim 60.