Method and apparatus for determining vehicle location based on motor feedback

• US 10,214,223 B1
• Filed: 04/05/2017
• Issued: 02/26/2019
• Est. Priority Date: 06/29/2012
• Status: Active Grant

• Current Assignee: Waymo LLC (Alphabet Inc.)
• Original Assignee: Waymo LLC (Alphabet Inc.)
• Inventors: Lombrozo, Peter Craig, Jensen, Carsten, Barton-Sweeney, Andrew, Smith, Russell, Larner, Daniel Lynn
• Primary Examiner(s): Smith, Isaac G
• Application Number:
  US15/479,707
• Time in Patent Office: 692 Days
• Field of Search: 701 22, 701408
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2050/0059 Signal noise suppression
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/12 Lateral speed
• CPC Class Codes: B60W 2556/00 Input parameters relating to data
• CPC Class Codes: B60W 30/00 Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 40/103 Side slip angle of vehicle body
• CPC Class Codes: B60W 40/105 Speed
• CPC Class Codes: B60W 50/00 Details of control systems for road vehicle drive control not related to the control of a particular sub-unit , e.g. process diagnostic or vehicle driver interfaces
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00

Abstract

A method and apparatus are provided for determining the location of a vehicle. According to one aspect the method and apparatus the movements of motor rotors in a vehicle are monitored and used to determine speed, travel distance and/or travel path of a vehicle may be determined. Using various navigation techniques, the distance and travel path may then be used to determine the vehicle'"'"'s location. Furthermore, movements of the motor rotors may also be used to report the positions of the steering and drive systems for the purpose of informing the vehicle controller as a method of feedback.

Claims

1. A method comprising:

receiving from a speedometer of a vehicle having an autonomous driving mode, a first current speed of the vehicle;

receiving, from a displacement measuring device, displacement information identifying a first orientation of a first rotor at a first time and a second orientation of the first rotor at a second time;

determining, by one or more computing devices having one or more processors, a second current speed of the vehicle by determining a displacement value between the first orientation and the second orientation;

determining, by the one or more computing devices, whether to continue using speeds determined by the speedometer to control the vehicle in the autonomous driving mode based on a difference between the first current speed and the second current speed; and

controlling, by the one or more computing devices, the vehicle in the autonomous driving mode based on the determination of whether to continue using speeds determined by the speedometer.

2. The method of claim 1, further comprising, filtering the displacement information to remove noise caused by a misalignment between the displacement measuring device and the first rotor of the vehicle.

3. The method of claim 1, wherein determining the second current speed is further based on whether the vehicle is performing a turn between the first time and the second time.

4. The method of claim 1, wherein determining whether to continue using speeds determined by the speedometer includes validating correctness of the speedometer.

5. The method of claim 1, wherein determining whether to continue using speeds determined by the speedometer includes determining that the speedometer has failed, and when the speedometer is determined to have failed, controlling the vehicle involves ignoring speeds determined by the speedometer.

6. The method of claim 1, wherein controlling the vehicle in the autonomous driving mode includes adjusting the speed of the vehicle when the speedometer is determined to have failed.

7. The method of claim 1, wherein the displacement measuring device includes a second rotor, a stator, and a controller circuit, and the first and second orientations are received from the controller circuit.

8. The method of claim 1, further comprising using the displacement measuring device to periodically sample the first orientation and the second orientation at a predetermined sampling rate.

9. The method of claim 1, further comprising periodically using a predetermined period of time:

receiving from the speedometer an updated current speed of the vehicle;

receiving, from the displacement measuring device, updated displacement information identifying an updated first orientation of the first rotor at a third time and an updated second orientation of the first rotor at a fourth time;

determining an updated second current speed of the vehicle by determining a displacement value between the updated first orientation and the updated second orientation; and

determining, by the one or more computing devices, whether to continue using speeds determined by the speedometer to control the vehicle in the autonomous driving mode based on a difference between the updated first current speed and the updated second current speed.

10. A system comprising one or more processors configured to:

receive from a speedometer a vehicle having an autonomous driving mode, a first current speed of the vehicle;

receive, from a displacement measuring device, displacement information identifying a first orientation of a first rotor at a first time and a second orientation of the first rotor at a second time;

determine a second current speed of the vehicle by determining a displacement value between the first orientation and the second orientation;

determine whether to continue using speeds determined by the speedometer to control the vehicle in the autonomous driving mode based on a difference between the first current speed and the second current speed; and

control the vehicle in the autonomous driving mode based on the determination of whether to continue using speeds determined by the speedometer.

11. The system of claim 10, wherein the one or more processors are further configured to filter the displacement information to remove noise caused by a misalignment between the displacement measuring device and the first rotor of the vehicle.

12. The system of claim 10, the one or more processors are further configured to determine the second current speed based on whether the vehicle is performing a turn between the first time and the second time.

13. The system of claim 10, wherein the one or more processors are further configured to determine whether to continue using speeds determined by the speedometer by validating correctness of the speedometer.

14. The system of claim 10, wherein the one or more processors are further configured to whether to continue using speeds determined by the speedometer by determining that the speedometer has failed, and when the speedometer is determined to have failed, controlling the vehicle involves ignoring speeds determined by the speedometer.

15. The system of claim 10, wherein the one or more processors are further configured to control the vehicle in the autonomous driving mode by adjusting the speed of the vehicle when the speedometer is determined to have failed.

16. The system of claim 10, wherein the displacement measuring device includes a second rotor, a stator, and a controller circuit, and the first and second orientations are received by the one or more processors from the controller circuit.

17. The system of claim 10, wherein the one or more processors are further configured to use the displacement measuring device to periodically sample the first orientation and the second orientation at a predetermined sampling rate.

18. The system of claim 10, wherein the one or more processors are further configured to periodically, using a predetermined period of time:

receive from the speedometer an updated current speed of the vehicle;

receive

from the displacement measuring device, updated displacement information identifying an updated first orientation of the first rotor at a third time and an updated second orientation of the first rotor at a fourth time;

determine an updated second current speed of the vehicle by determining a displacement value between the updated first orientation and the updated second orientation; and

determine whether to continue using speeds determined by the speedometer to control the vehicle in the autonomous driving mode based on a difference between the updated first current speed and the updated second current speed.

19. The system of claim 10, further comprising the vehicle.

20. The system of claim 10, further comprising the displacement measuring device.