Traffic data management and simulation system

• US 20020198694A1
• Filed: 06/24/2002
• Published: 12/26/2002
• Est. Priority Date: 06/22/2001
• Status: Active Grant

• Current Assignee: Caliper Corporation
• Original Assignee: Caliper Corporation
• Inventors: Yang, Qi, Brandon, Jonathan, Slavin, Howard, Olsberg, Simon, LaClair, Mary, Rabinowicz, Andres, Stefansson, Kjartan
• Granted Patent: US 7,155,376 B2
• Time in Patent Office: Days
• US Class Current: 703/6
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30
• CPC Class Codes: G08G 1/0112 from the vehicle, e.g. floating car data [FCD]
• CPC Class Codes: G08G 1/0129 for creating historical data or processing based on historical data
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image

Abstract

Systems and methods for, inter alai, geographically based analyses of traffic being carried over a wide scale traffic network. The systems integrate geographical information systems (GIS) with traffic simulation processes to allow a user to analyze traffic patterns and loads at specific geographic locations of regions. Additionally, these systems allow for traffic analysis over a wide scale traffic network that may encompass the traffic network that exists within an geographic region and can include, as examples, the traffic networks that span across a city, that interconnect cities, that interconnect states and that run across multiple states. To this end, the systems include traffic simulators that can adaptively or controllably select between multiple traffic simulation models for simulating traffic across different segments of the traffic network. The different models provide varying levels of granularity for measurements of geographical location of a vehicle traveling over the traffic network. Thus portions of the traffic network that are to be analyzed more closely can use the traffic simulator model with the highest degree of granularity, while traffic patterns across other areas of the network may be modeled with lower granularity models that may provide for computational efficiency.

Claims

1. A system for analyzing traffic flow, comprising:

a GIS database manager for allowing a user to form spatial queries representative of queries formed from at least one spatial characteristic,

a GIS database having a network representation of a transportation environment and being responsive to said GIS database manager for processing said spatial queries,

a traffic simulator for simulating, as a function of the network representation, a flow of traffic across the transportation environment, and

a database interface responsive to said traffic simulator for processing simulation data and for creating GIS data representative of time varying traffic data and for modifying demand data stored in said GIS database.

2. A system according to claim 1, further comprising

an animator process for processing said network representation and said time varying traffic data to generate a visual animation of traffic flow across the transportation environment where the network and vehicle objects may be thematically represented with respect to values of traffic data attributes.

3. A system according to claim 1, further comprising

an editor for editing the demand table to create a modified simulation.

4. A system according to claim 1, further comprising:

an editor for editing the network representation to create a modified transportation environment.

5. A system according to claim 1, wherein the GIS database includes a network representation having information representative of geographical coordinates of the transportation environment.

6. A system according to claim 1, wherein the network representation includes a network formed of links and nodes.

7. A system according to claim 1, further including storage for a link/node attribute representative of a traffic simulation model to apply to a portion of the network representation for simulating movement of a vehicle.

8. A system according to claim 7, wherein the network representation includes a plurality of links connected at a plurality of nodes, and having storage associated with at least one node for storing a link/node attribute representative of a traffic simulation model to apply during a traffic simulation process to links coupled to the respective node.

9. A system according to claim 7, wherein the link/node attribute may be representative of a microscopic, mesoscopic or macroscopic model.

10. A system according to claim 7, wherein the network representation includes links and nodes and wherein the link/node attributes are associated with nodes occurring within the network representation.

11. A system according to claim 7, further including means for associating a segment of the network representation with a selected link/node attribute.

12. A system according to claim 7, further including means for transitioning between traffic simulation models in response to a vehicle mapped on a first part of the network representation being mapped to a second part of the network representation.

13. A system according to claim 1, wherein the network representation of the transportation environment includes storage for data representative of three dimensional world coordinates.

14. A system according to claim 13, further including

a user interface that presents data in a graphical form that employs geographical data in the database to create a geographically accurate graphical representation of the traffic environment.

15. A system according to claim 1, wherein the traffic simulator includes

means for simulating behavioral characteristics of a driver.

16. A system according to claim 1, wherein the traffic simulator includes

a route selector for selecting a route for a vehicle to travel to traverse from an origin to a destination.

18. A process according to claim 17, further comprising providing a link/node attribute with the network representation to associate a traffic simulation model with at least a portion of the network representation.

19. A process according to claim 17, wherein the network representation includes links and nodes and further comprising

associating a link/node attribute with a node occurring within the network representation.

20. A process according to claim 19, further comprising

simulating movement of a vehicle across a link as a function of a link/node attribute associated with a node to which the link connects.

21. A process according to claim 19, further comprising

identifying a link that connects between two nodes having different link/node attributes and dividing the link into two separate segments, a first segment associated with one link/node attribute and a second segment associated with the other link/node attribute, each segment being associated with a geographical location.

22. A process according to claim 21, further comprising

monitoring the geographical location of a vehicle and determining when the vehicle simulation moves the vehicle from the first segment to the second segment and responding to the change in link/node attribute by changing the model employed to simulate movement of the vehicle.

25. A method according to claim 25 wherein

traffic data includes information on intersections, road, lanes, traffic signals and signs, surveillance sensors, vehicles, transit, signal timings, historical travel times, and estimates of travel demand.

26. A method according to claim 25, further including

providing a database manager for forming spatial queries of traffic network objects and data associated with them.

27. A method according to claim 25, further including

joining external datatables of geocoded objects to geocoded information representative of a transportation environment.

17. A process for analyzing traffic flow, comprising

creating a GIS database having information representative of a network representation of a transportation environment and information representative of traffic demands placed on the respective transportation environment,

providing a GIS database manager for applying spatial queries to said GIS database representative of queries formed from at least one spatial characteristic, for identifying traffic demand at selected geographical coordinates,

simulating, as a function of time, the network representation, and the traffic demand information, a flow of traffic across the transportation environment, and

updating traffic demand information within the GIS database for creating GIS data representative of time varying traffic data, whereby spatial queries can be applied to the GIS database for performing a dynamic analysis of traffic flow.

23. A process for simulating traffic flow across a heterogeneous transportation environment, comprising

creating a GIS database having information representative of a network representation of a transportation environment including at least two types of roadways and information representative of traffic demands placed on the respective transportation environment,

associating with a first type of roadways within the network representation a link/node attribute representative of a traffic simulation model to apply during a traffic simulation process of vehicles moving across the first type of roadways and associating with a second type of roadways a different link/node attribute to apply during a traffic simulation process of vehicles moving across the second type of roadways,

providing a GIS database manager for applying spatial queries to said GIS database representative of queries formed from at least one spatial characteristic, for identifying traffic demand at selected geographical coordinates,

simulating, as a function of time, the network representation, the traffic demand information, and the link/node attributes, a flow of traffic across the transportation environment,

determining when a vehicle from the first type of roadway to the second type of roadway and responding to the change in link/node attribute by changing the model employed to simulate movement of the vehicle, and

updating traffic demand information within the GIS database for creating GIS data representative of time varying traffic data, whereby spatial queries can be applied to the GIS database for performing a dynamic analysis of traffic flow across a heterogeneous transportation environment.

24. We claim a method of traffic simulation, comprising

geocoding information representative of a transportation environment that encompasses a large geographic area,

applying integrated simulation at different levels of detail for different portions of the network to model traffic flows over a large area by applying integrated simulation at different levels of details for different elements of the networks, and

updating a database of traffic demand representative of the traffic volume at a geographic location on the transportation environment.