Rating that represents the status along a specified driving route

• US 7,203,595 B1
• Filed: 03/15/2006
• Issued: 04/10/2007
• Est. Priority Date: 03/15/2006
• Status: Active Grant

• Current Assignee: HERE Global B.V. (Nokia Corporation)
• Original Assignee: Trafficcom Incorporated (Nokia Corporation)
• Inventors: Carroll, James F., Smyth, Brian J., Auxer, Gregory A.
• Primary Examiner(s): Zanelli; Michael J.
• Application Number:
  US11/376,731
• Time in Patent Office: 391 Days
• Field of Search: None
• US Class Current: 701/117
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G01C 21/3691 Retrieval, searching and output of information related to real-time traffic, weather, or environmental conditions arrangements for giving variable traffic instructions G08G1/09
• CPC Class Codes: G06Q 30/00 Commerce
• CPC Class Codes: G08G 1/0104 Measuring and analyzing of parameters relative to traffic conditions

Abstract

A Jam Factor rating is provided that represents the status along a specified driving route. The driving route is specified such that the route includes at least one road. A free flow travel time is calculated for the specified route. Then, the total delay is calculated for the specified route. The free flow travel time and the total delay are summed to obtain the total estimated travel time along the specified route. A delay multiple is then calculated by dividing the total travel time by the free flow travel time. The Jam Factor rating is then calculated based on the delay multiple.

Claims

1. A computer-implemented method of calculating a rating that represents the status along a specified driving route comprising:

(a) specifying a driving route, such that the route includes at least one road;

(b) calculating the free flow travel time for the specified route;

(c) calculating the total delay along the specified route;

(d) summing the free flow travel time and the total delay to obtain the total estimated travel time;

(e) calculating a delay multiple by dividing the total travel time by the free flow travel time; and

(f) calculating a rating based on the delay multiple.

2. The method of claim 1 wherein the total delay along the specified route includes a congestion delay.

3. The method of claim 2 wherein the congestion delay is calculated by:

(i) identifying areas of congestion along the route,

(ii) determining the length of each area of congestion,

(iii) determining an average speed for each area of congestion,

(iv) calculating the travel time for each area of congestion by dividing the length of the area by the average speed for that area,

(v) calculating the congestion delay for each area by subtracting the free flow travel time for that area from the travel time for that area,

(vi) summing the congestion delays for each area of congestion along the route.

4. The method of claim 1 wherein the total delay along the specified route includes an incident delay.

5. The method of claim 4 wherein the incident delay is calculated by:

(i) identifying incidents along the route,

(ii) determining the criticality of each incident along the route,

(iii) determining an incident delay associated with each incident along the route which is based upon the criticality of the incident, and

(iv) summing the incident delays for each incident along the route.

6. The method of claim 1 wherein the total delay along the specified route includes a digital delay calculated from sensor values.

7. The method of claim 1 wherein the total delay along the specified route includes a digital delay calculated from sensor values using the equation:

$\mathrm{DigitalDelay}=\frac{\mathrm{RouteLength}}{\mathrm{SensorSpeed}}-\frac{\mathrm{RouteLength}}{\mathrm{SpeedLimit}}$

8. The method of claim 1 wherein the rating is directly associated to the delay multiple by an exponential equation where the rating equals 0 when the delay multiple equals 1 and the rating approaches 10 as the delay multiple grows very large.

9. The method of claim 1 wherein the rating is calculated from a table containing ratings for discreet values of the delay multiple by linearly interpolating the rating for values for the delay multiple which fall in between the discreet values contained in the table using the equation:

$\mathrm{Rating}=\frac{{\mathrm{Rating}}_{\mathrm{next}}-{\mathrm{Rating}}_{\mathrm{prev}}}{{\mathrm{DelayMultiple}}_{\mathrm{next}}-{\mathrm{DelayMultiple}}_{\mathrm{prev}}}*\left({\mathrm{DelayMultiple}}_{\mathrm{actual}}-{\mathrm{DelayMultiple}}_{\mathrm{next}}\right)+{\mathrm{Rating}}_{\mathrm{next}}$

10. The method of claim 1 wherein the free flow travel time for a specified route is calculated by dividing the length of the route by the speed limit for the route.

11. The method of claim 1 wherein any road closure along the specified driving route automatically creates a rating of 10.

12. The method of claim 1 wherein the specified driving route is a keyroute, the keyroute being one or more road segments.