Methods and systems for deducing road geometry and connectivity

• US 20060155464A1
• Filed: 11/30/2005
• Published: 07/13/2006
• Est. Priority Date: 11/30/2004
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Circumnav Networks Inc (Blackberry Limited)
• Inventors: Smartt, Brian E.
• Granted Patent: US 7,957,893 B2
• Time in Patent Office: Days
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3819 Road shape data, e.g. outline of a route
• 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: G08G 1/01 Detecting movement of traffic to be counted or controlled G08G1/07 - G08G1/14 take precedence
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles

Abstract

Methods and systems for generating, deriving, and enhancing drivable road databases are provided. A baseline road in a road network is defined and position and/or trajectory data collected by vehicles traveling the baseline road are compiled and compared to a representation of the baseline road in an existing database. Identity and/or other property information about the road are assigned form the existing database to the new database.

Claims

1. A method for generating an improved database representing a road network, comprising the steps of:

defining a baseline road in the road network, the defining comprising replacing an original representation of the baseline road in the database with new data, the new data having a greater accuracy than the original representation;

collecting the new data from a vehicle traveling a route in the road network;

dividing the route into one or more route segments;

assigning each route segment as an on-baseline segment, an off-baseline segment, an off-baseline to on-baseline transition, an on-baseline to off-baseline transition, or a within-baseline transition;

processing the collected data for each route segment.

2. The method of claim 1, wherein the assigning further comprises the steps of:

discretizing the route data to each of the route segments according to a measure of flow.

3. The method of claim 1, further comprising the steps of:

correlating data collected on an off-baseline segment to an off-baseline road, the off-baseline road being represented by an unrefined data set in the database;

gauging a measure of “

fit”

between the subset of collected data and the unrefined data set; and

adjusting the unrefined data set to incorporate information provided by the collected data.

4. A method for generating an improved database representing a road network, comprising the steps of:

recording a plurality of vehicle position data points from one or more vehicles traveling on a baseline road, such that all of the available directions of travel on the baseline road are traveled by at least one of the one or more vehicles;

compiling the vehicle position data;

connecting the recorded data points to form a semi-continuous trace of the geometric shape of the baseline road;

comparing the trace to a representation of the baseline road in an existing database that comprises road identities and/or properties; and

assigning one or more of the identities and/or properties from the existing database to the baseline road representation in the improved database.

5. The method of claim 4, wherein the periodic data points are determined by a position determination method that uses periodic sampling.

6. The method of claim 5, wherein the position determination method comprises the step of determining the vehicle position with a global positioning system (GPS) transceiver.

7. A method for deducing road connectivity comprising the steps of:

recording a plurality of vehicle position data points from a vehicle traveling a route, the route comprising a first road segment and a second road segment, the route further comprising a junction between the first road segment and the second road segment;

discretizing the vehicle position data points based on a measure of flow such that the data points are binned into categories;

aggregating the semi-continuous traces for the roads into a database that represents one or more road connections generally followed by vehicles traveling on the roads.

8. The method of claim 7, further comprising the steps of:

combining the aggregated trace database with a conventional map database to form a single, functional, routing, navigation and traffic data collection set.

9. The method of claim 7, further comprising the step of:

calculating a recommended route, the recommended route comprising the first road segment, the second road segment and the junction; and

determining turn-by-turn guidance instructions for a vehicle following the recommended route.