Method for accelerometer-assisted navigation

Patent metadata

Field	Value
Publication number	US-9733089-B2
Application number	US-201615243513-A
Country	US
Kind code	B2
Filing date	Aug 22, 2016
Priority date	Aug 20, 2015
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A method for primarily sensor-based navigation includes: in a first time period, collecting geophysical position data using a GPS receiver of a navigation device; in the first time period, collecting a first set of accelerometer data using an accelerometer of the navigation device; analyzing the first set of accelerometer data to produce a first set of vertical vehicular motion data; generating a mapping association between the first set of vertical vehicular motion data and the geophysical position data; in a second time period after the first time period, collecting a second set of accelerometer data using the accelerometer; analyzing the second set of accelerometer data to produce a second set of vertical vehicular motion data; and calculating an estimated location of the vehicle by analyzing the second set of vertical vehicular motion data in light of the mapping association.

First claim

We claim:

1. A method for primarily sensor-based navigation of a vehicle on a road surface, the method comprising:
in a first time period, collecting geophysical position data using a GPS receiver of a navigation device;
in the first time period, collecting a first set of accelerometer data using an accelerometer of the navigation device;
analyzing the first set of accelerometer data to produce a first set of vertical vehicular motion data; wherein vertical vehicular motion data describes motion of the vehicle perpendicular the road surface;
generating a mapping association between the first set of vertical vehicular motion data and the geophysical position data;
in a second time period after the first time period, collecting a second set of accelerometer data using the accelerometer;
analyzing the second set of accelerometer data to produce a second set of vertical vehicular motion data; and
calculating an estimated location of the vehicle by analyzing the second set of vertical vehicular motion data in light of the mapping association.

2. The method of claim 1 , further comprising:
generating a set of previously traveled routes, each previously traveled route of the set of previously traveled routes associated with geophysical positions previously mapped to vertical vehicular motion data;
receiving, at the navigation device, a travel source and a travel destination;
determining that a first previously traveled route from the set of previously traveled routes intersects the travel source, the travel destination, and the estimated location of the vehicle; and
navigating the vehicle according to the first previously traveled route.

3. The method of claim 2 , further comprising, in response to identifying the first previously traveled route, switching off the GPS receiver; wherein navigating the vehicle according to the first previously traveled route comprises navigating based on vertical vehicular motion data without collecting additional GPS data.

4. The method of claim 3 , wherein receiving, at the navigation device, a travel source and a travel destination comprises receiving a user-submitted travel source and a user-submitted travel destination.

5. The method of claim 3 , wherein receiving, at the navigation device, a travel source and a travel destination comprises receiving a GPS-inferred travel source and a user-submitted travel destination.

6. The method of claim 3 , wherein receiving, at the navigation device, a travel source and a travel destination comprises receiving a GPS-inferred travel source and further comprises predicting a predicted travel destination from the GPS-inferred travel source, a current time, and a historical analysis of the set of previously traveled routes.

7. The method of claim 1 , further comprising calculating a location estimate error; and, in response to the location estimate error falling below a location estimate error threshold, disabling the GPS receiver and navigating based on vertical vehicular motion data without collecting additional GPS data.

8. The method of claim 7 , wherein calculating a location estimate error comprises calculating a location estimate error based on a comparison of a GPS-derived location, derived from a second set of geophysical position data collected by the GPS receiver in the second time period, and the estimated location of the vehicle.

9. The method of claim 7 , wherein calculating a location estimate error comprises calculating a location estimate error based on a comparison of a GPS-and-accelerometer-derived location and the estimated location of the vehicle; wherein the method further comprises deriving, in the second time period, the GPS-and-accelerometer-derived location by:
inferring a GPS-measured initial vehicular location from a second set of geophysical position data collected by the GPS receiver; wherein the geophysical position data is collected at a first time between the first time period and the second time period;
collecting a third set of accelerometer data between the first time and a second time in the second time period;
analyzing the third set of accelerometer data to produce a first set of horizontal vehicular motion data;
calculating a vehicle position change from the first set of horizontal vehicular motion data; and
calculating the GPS-and-accelerometer-derived location by adding the vehicle position change to the GPS-measured initial vehicular location.

10. The method of claim 1 , wherein calculating an estimated location of the vehicle comprises:
inferring a GPS-measured initial vehicular location from a second set of geophysical position data collected by the GPS receiver; wherein the geophysical position data is collected at a first time between the first time period and the second time period;
generating a set of potential locations, each potential location of the set of potential locations associated with a vertical vehicular motion profile; and
calculating the estimated location of the vehicle from the set of potential locations based on both of proximities of the set of potential locations to the GPS-measured initial vehicular location and correlations of the vertical vehicular motion profiles to the second set of vertical vehicular motion data.

11. The method of claim 1 , wherein calculating an estimated location of the vehicle comprises:
inferring a GPS-measured initial vehicular location from a second set of geophysical position data collected by the GPS receiver; wherein the geophysical position data is collected at a first time between the first time period and the second time period;
collecting a third set of accelerometer data between the first time and a second time in the second time period;
analyzing the third set of accelerometer data to produce a first set of horizontal vehicular motion data;
calculating a vehicle position change from the first set of horizontal vehicular motion data;
calculating a GPS-and-accelerometer-derived location by adding the vehicle position change to the GPS-measured initial vehicular location;
generating a set of potential locations, each potential location of the set of potential locations associated with a vertical vehicular motion profile; and
calculating the estimated location of the vehicle from the set of potential locations based on both of proximities of the set of potential locations to the GPS-and-accelerometer-derived location and correlations of the vertical vehicular motion profiles to the second set of vertical vehicular motion data.

12. The method of claim 1 , wherein calculating an estimated location of the vehicle comprises:
inferring a GPS-measured initial vehicular location from a second set of geophysical position data collected by the GPS receiver; wherein the geophysical position data is collected at a first time between the first time period and the second time period;
collecting a third set of accelerometer data between the first time and a second time in the second time period;
analyzing the third set of accelerometer data to produce a first set of horizontal vehicular motion data;
calculating a vehicle position change from the first set of horizontal vehicular motion data;
calculating a GPS-and-accelerometer-derived location by adding the vehicle position change to the GPS-measured initial vehicular location;
calculating a vertical-accelerometer-derived location and a vertical-accelerometer confidence by analyzing the second set of vertical vehicular motion data in light of the mapping association; and
selecting one of the GPS-and-accelerometer-derived location and the vertical-accelerometer-derived location as the estimated location of the vehicle based on the vertical-

Assignees

• Zendrive Inc

Inventors

• Choudhury Romit Roy
• Pal Jayanta
• Risbood Pankaj
• Matus Jonathan

Classifications

• G01C21/30

  Map- or contour-matching · CPC title

• G01C21/165 Primary

  combined with non-inertial navigation instruments · CPC title