Method for initiating navigation guidance in a distributed communications system

• US 20060184315A1
• Filed: 02/14/2005
• Published: 08/17/2006
• Est. Priority Date: 02/14/2005
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Uribe, Juan C., Liu, Kunwel Mike, Bhaskaran, Parvathy, Clayton, Richard M., Saxena, Garurank P., Weisshaar, Bernhard P.
• Granted Patent: US 7,418,339 B2
• Time in Patent Office: Days
• US Class Current: 701/202
• CPC Class Codes: G01C 21/34 Route searching; Route guidance
• CPC Class Codes: G08G 1/096811 where the route is computed offboard
• CPC Class Codes: G08G 1/096816 where the complete route is transmitted to the vehicle at once
• CPC Class Codes: G08G 1/09685 where the complete route is computed only once and not updated

Abstract

A method is provided for improved navigation guidance in a portable navigation device (104) having a first navigation operating mode (302) for requesting (318, 324) and receiving (326, 334) routelet data and navigation route data and operating in accordance with the routelet data (332) and a second operation navigation mode (304) for operating in accordance with the navigation route data (338). The method includes in the first navigation operating mode (302), the steps of transmitting a routelet request (318) comprising location data, speed data and direction data, the location, speed and direction data determined (312, 314 316) in response to a present location, a present speed and a present direction of travel, respectively, of the portable navigation device (104), receiving routelet data (326) and operating in accordance with the received routelet data (332).

Claims

1. A method for navigation guidance in a portable navigation device having a first navigation operating mode for requesting and receiving routelet data and navigation route data and operating in accordance with the routelet data and a second operation navigation mode for operating in accordance with the navigation route data, the method comprising the steps of:

in the first navigation operating mode, transmitting a routelet request comprising location data, speed data and direction data, the location, speed and direction data determined in response to a present location, a present speed and a present direction of travel, respectively, of the portable navigation device;

receiving routelet data; and

operating in accordance with the received routelet data.

2. The method for navigation guidance of claim 1 further comprising the steps of:

in the first navigation operating mode, transmitting a navigation route request comprising location data and a destination location, the location data determined in response to a present location of the portable navigation device when the navigation route request is transmitted; and

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to the received routelet data intersecting a main route, the main route defined by received navigation route data comprising routing data describing the main route from a route start location, determined in response to the first location data, to the destination location.

3. The method for navigation guidance of claim 2 wherein the step of switching operation of the portable navigation device comprises the steps of:

repeating the steps of transmitting a routelet request, receiving routelet data and operating in accordance with the received routelet data if the received routelet data is not applicable to a present location of the portable navigation device when the received routelet data is received; and

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to the received routelet data intersecting the main route.

4. The method for navigation guidance of claim 2 wherein the step of switching operation of the portable navigation device comprises the steps of:

receiving navigation route data comprising routing data and received routelet data, the routing data describing the main route to navigate from the route start location to the destination location;

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to the received routelet data intersecting the main route.

5. The method for navigation guidance of claim 2 wherein the step of switching operation of the portable navigation device comprises the steps of:

repeating the steps of transmitting a routelet request, receiving routelet data and operating in accordance with the received routelet data if the received routelet data is not applicable to a present location of the portable navigation device when the received routelet data is received or if the received routelet data does not intersect with the main route; and

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to the received routelet data intersecting the main route.

6. The method for navigation guidance of claim 1 further comprising the step of providing a user indication of off road status in response to the routelet data including off road indication data.

7. In a distributed navigation guidance system comprising a portable navigation device and a remote navigation guidance device, a method in the remote navigation guidance device for navigation guidance of the portable navigation device, the method comprising the steps of:

receiving a routelet request comprising location data, speed data and direction data, the location data, speed data and direction data determined in response to a present location, a present speed and a present direction of travel, respectively, of the portable navigation device at the time the routelet request was transmitted;

generating routelet data in response to the location data, the speed data, the direction data and at least one primary travel road within a predetermined distance from the portable navigation device as indicated by the location data; and

transmitting the routelet data to the portable navigation device.

8. The method in the remote navigation guidance device for navigation guidance of claim 7 further comprising the steps of:

receiving a navigation route request comprising first location data and a destination location, the first location data determined in response to a present location of the portable navigation device when the navigation route request is transmitted;

generating navigation route data comprising routing data describing a main route from a route start location, determined in response to the first location data, to the destination location;

generating initial routelet data describing at least one routelet from the present location of the portable navigation device when the navigation route request is transmitted that intersects the main route; and

transmitting the navigation route data and the initial routelet data to the portable navigation device.

9. The method in the remote navigation guidance device for navigation guidance of claim 7 wherein the step of generating routelet data comprises the steps of:

determining a nearest road segment to the portable navigation device in response to the location data and predetermined road information; and

determining whether the portable navigation device is located on road or located off road in response to the location data and the nearest road segment.

10. The method in the remote navigation guidance device for navigation guidance of claim 9 wherein the step of generating routelet data further comprises the steps of:

determining that the portable navigation device is located on road in response to the location data indicating that the portable navigation device is less than a predetermined distance from the nearest road segment;

determining that the portable navigation device is stationary in response to the speed data indicating that the portable navigation device is traveling at a speed less than a predetermined speed; and

generating routelet data for travel in a routelet area defined in response to the location data, the speed data and the direction data, the routelet data defined in response to the location data and a main route if the portable navigation device is located on road and the portable navigation device is stationary, the main route defined in response to a route start location and a destination location.

11. The method in the remote navigation guidance device for navigation guidance of claim 9 wherein the step of generating routelet data further comprises the steps of:

determining that the portable navigation device is located on road in response to the location data indicating that the portable navigation device is less than a predetermined distance from the nearest road segment;

determining that the portable navigation device is moving in response to the speed data indicating that the portable navigation device is traveling at a speed greater than or equal to a predetermined speed; and

generating routelet data for travel in a routelet area defined in response to the speed data and the direction data, the routelet data defined in response to the location data and a main route if the portable navigation device is located on road and the portable navigation device is moving, the main route defined in response to a route start location and a destination location.

12. The method in the remote navigation guidance device for navigation guidance of claim 9 wherein the step of generating routelet data further comprises the steps of:

determining that the portable navigation device is located off road in response to the location data indicating that the portable navigation device is greater than or equal to a predetermined distance from the nearest road segment;

determining that the portable navigation device is stationary in response to the speed data indicating that the portable navigation device is traveling at a speed less than a predetermined speed; and

generating routelet data for travel in a routelet area defined in response to the location data, the speed data and the direction data, the routelet data defined in response to the location data and the nearest road segment if the portable navigation device is located off road and the portable navigation device is stationary, and wherein the routelet data further comprises off road indication data if the portable navigation device is located off road and the portable navigation device is stationary.

13. The method in the remote navigation guidance device for navigation guidance of claim 9 wherein the step of generating routelet data further comprises the steps of:

determining that the portable navigation device is located off road in response to the location data indicating that the portable navigation device is greater than or equal to a predetermined distance from the nearest road segment;

determining that the portable navigation device is moving in response to the speed data indicating that the portable navigation device is traveling at a speed greater than a predetermined speed; and

generating routelet data for travel in a routelet area defined in response to the speed data and the direction data, the routelet data defined in response to the location data, the nearest road segment and a main route if the portable navigation device is located off road and the portable navigation device is moving, the main route defined in response to a route start location and a destination location.

14. A method for navigation guidance in a distributed navigation guidance system comprising a portable navigation device and a remote navigation guidance device, the portable navigation device having a first navigation operating mode for requesting and receiving routelet data and navigation route data and operating in accordance with the routelet data and a second operation navigation mode for operating in accordance with the navigation route data, the method comprising:

transmitting from the portable navigation device operating in the first operation mode a routelet request comprising location data, speed data and direction data, the location, speed and direction data determined in response to a present location, a present speed and a present direction of travel, respectively, of the portable navigation device;

receiving the routelet request at the remote navigation guidance device;

the remote navigation guidance device generating routelet data in response to the location data, the speed data, the direction data and at least one primary travel road within a predetermined distance from the portable navigation device as indicated by the location data;

transmitting the routelet data from the remote navigation device;

the portable navigation device receiving the routelet data; and

the portable navigation device operating in accordance with the received routelet data.

15. The method for navigation guidance of claim 14 further comprising the steps of:

transmitting from the portable navigation device in the first navigation operating mode, a navigation route request comprising location data and a destination location, the first location data determined in response to a present location of the portable navigation device when the navigation route request is transmitted;

receiving the navigation route request at the remote navigation guidance device;

at the remote navigation guidance device generating navigation route data comprising routing data describing a main route from a route start location, determined in response to the first location data, to the destination location;

generating initial routelet data describing at least one routelet from the present location of the portable navigation device when the navigation route request is transmitted that intersects the main route;

transmitting the navigation route data and the initial routelet data from the remote navigation device;

receiving the navigation route data and the initial routelet data at the portable navigation device;

the portable navigation device determining whether the initial routelet data is applicable to a present location of the portable navigation device when the initial routlet data is received; and

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to the initial routelet data being applicable to the present location of the portable navigation device.

16. The method for navigation guidance of claim 14 further comprising the steps of:

the portable navigation device determining whether navigation route data comprising routing data describing a main route to navigate from a route start location to a destination location has been received;

the portable navigation device determining whether the routelet data intersects the main route;

repeating the steps of transmitting a routelet request, receiving the routelet request, generating routelet data, transmitting the routelet data, receiving the routelet data and operating in accordance with the received routelet data if the routelet data is determined to not intersect the main route; and

switching operation of the portable navigation device from the first navigation operating mode to the second navigation operating mode in response to routelet data intersecting the main route.