Propagation of position with multiaxis accelerometer

• US 20020022924A1
• Filed: 03/07/2001
• Published: 02/21/2002
• Est. Priority Date: 03/07/2000
• Status: Abandoned Application

• Current Assignee: Magellan DIS, Inc.
• Original Assignee: Magellan DIS, Inc.
• Inventors: Begin, John David
• Application Number:
  US09/800,609
• Publication Number:
  US 20020022924A1
• Time in Patent Office: Days
• US Class Current: 701/207
• CPC Class Codes: G01C 21/185 for gravity
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network

Abstract

A vehicle navigation system and method for propagating a position of a vehicle utilizing a multiaxis accelerometer determines the pitch and roll of the vehicle without utilizing gyros and utilizes the calculated pitch and roll to propagate the position of the vehicle with the acceleration signals from the multiaxis accelerometer. This occurs in one of three situations (in order of complexity): 1) when the vehicle is not moving; 2) when the vehicle is moving and other speed and/or heading information is available and 3) when the vehicle is moving and other speed and/or heading information is not available.

Claims

1. A method of propagating a previous position to a current position in a vehicle navigation system, said method including the steps of:

a) providing longitudinal acceleration information;

b) providing vertical acceleration information;

c) determining a pitch of the vehicle from said vertical acceleration information and said longitudinal acceleration information; and

d) using said pitch to propagate a previous position to a current position.

2. The method of claim 1 further including the step of determining a change in said pitch from said vertical acceleration information and said longitudinal acceleration information.

3. The method of claim 2 wherein said step c) is performed without information from a rotation sensor.

4. A method of propagating a previous position to a current position in a vehicle navigation system, said method including the steps of:

a) providing longitudinal acceleration information and vertical acceleration information;

b) providing heading information; and

c) determining roll of the vehicle based upon said vertical acceleration information, said longitudinal acceleration information and said heading information.

5. The method of claim 4 further including the step of using said heading to propagate a previous position to a current position.

6. The method of claim 5 further including the step of using said heading to propagate a previous position to a current position

7. The method of claim 4 further including the step of obtaining said heading information from map-matching.

8. The method of claim 4 further including the step of obtaining said heading information from GPS velocity information .

9. The method of claim 4 wherein said step c) is performed without information from a gyro.

10. A method of propagating a previous position to a current position in a vehicle navigation system, said method including the steps of:

a) providing longitudinal acceleration information and vertical acceleration information;

b) providing speed information; and

c) determining pitch based upon said vertical acceleration information, said longitudinal acceleration information and said speed information

11. The method of claim 10 further including the step of using said pitch to propagate a previous position to a current position.

12. The method of claim 11 further including the step of obtaining said speed information from GPS velocity information.

14. The method of claim 13 wherein said steps a) and b) are performed while the vehicle is moving.

15. The method of claim 13 further including the steps of:

e) determining whether the vehicle is not moving; and

f) performing said steps a) and b) based upon said step e) when said vehicle is not moving.

16. The method of claim 13 further including the steps of:

d) monitoring the plurality of signals to determine a low noise situation; and

e) performing said step b) based upon said step d).

13. A method for propagating a previous position to a current position in a vehicle navigation system, said method including the steps of:

a) receiving a plurality of signals from an inertial sensor mounted in a vehicle;

b) determining a pitch of the vehicle based upon the plurality of signals; and

c) propagating a previous position to a current position based upon the plurality of signals and said pitch as determined in said step b).