Devices and methods for a sensor platform of a vehicle

Patent metadata

Field	Value
Publication number	US-11209276-B2
Application number	US-201916674159-A
Country	US
Kind code	B2
Filing date	Nov 5, 2019
Priority date	Sep 20, 2016
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

In one example, a vehicle includes a platform and a yaw sensor mounted on the platform. The yaw sensor provides an indication of a yaw rate of rotation of the yaw sensor. The vehicle also includes an actuator that rotates the platform. The vehicle also includes a controller coupled to the yaw sensor and the actuator. The controller receives the indication of the yaw rate from the yaw sensor. The controller also causes the actuator to rotate the platform (i) along a direction of rotation opposite to a direction of the rotation of the yaw sensor and (ii) at a rate of rotation based on the yaw rate of the yaw sensor. The controller also estimates a direction of motion of the vehicle in an environment of the vehicle based on at least the rate of rotation of the platform.

First claim

What is claimed is:

1. A vehicle comprising:
a platform;
a yaw sensor mounted on the platform, wherein the yaw sensor is configured to measure a yaw rate of rotation of the yaw sensor relative to a yaw axis of the vehicle;
an actuator that rotates the platform; and
a controller coupled to the yaw sensor and the actuator, wherein the controller:
receives, from the yaw sensor, an indication of the yaw rate of rotation of the yaw sensor in a first direction relative to the yaw axis of the vehicle;
causes the actuator to rotate the platform at a rate of rotation in a second direction based on the yaw rate of rotation of the yaw sensor in the first direction
relative to the yaw axis of the vehicle, wherein the second direction is opposite to the first direction sensor; and
estimates, based on at least the rotation of the platform caused by the actuator, a change in a direction of motion of the vehicle in an environment of the vehicle.

2. The vehicle of claim 1 , further comprising:
a pitch sensor mounted on the platform that provides output indicative of a pitch orientation of the vehicle about a pitch axis of the vehicle, wherein the controller estimates the change in the direction of the vehicle based also on the output from the pitch sensor.

3. The vehicle of claim 2 , further comprising:
a roll sensor mounted on the platform that provides output indicative of a roll orientation of the vehicle about a roll axis of the vehicle, wherein the controller estimates the change in the direction of the vehicle based also on the output from the pitch sensor is in response to the roll orientation being at a threshold to a given roll orientation.

4. The vehicle of claim 1 , further comprising:
a second actuator coupled to the platform to adjust a tilting angle of the platform, wherein the tilting angle corresponds to an offset to a yaw axis of the yaw sensor, the offset associated with a roll rotation or a pitch rotation of the vehicle.

5. The vehicle of claim 4 , wherein the vehicle is an autonomous vehicle, wherein the controller receives an indication of an expected change to the direction of motion of the vehicle based on a predetermined navigation path of the vehicle, and wherein the controller causes the second actuator to adjust the tilting angle of the platform based on at least the received indication.

6. The vehicle of claim 4 , further comprising a roll sensor that provides output indicative of a roll orientation of the vehicle about a roll axis, wherein the controller receives an indication of a change to the roll orientation of the vehicle from the roll sensor, and wherein the controller causes the second actuator to adjust the tilting angle of the platform based on at least the received indication.

7. The vehicle of claim 1 , wherein the yaw sensor is a first yaw sensor, wherein the yaw rate is a first yaw rate, the vehicle further comprising:
a second yaw sensor that provides an indication of a second yaw rate of rotation of the second yaw sensor, wherein the first yaw sensor is mounted to the vehicle at a first tilting angle such that a first yaw axis of the first yaw sensor is at a first offset to the yaw axis of the vehicle, and wherein the second yaw sensor is mounted to the vehicle at a second tilting angle such that a second yaw axis of the second yaw sensor is at a second offset to the yaw axis of the vehicle.

8. The vehicle of claim 7 , wherein the controller estimates the change in the direction of motion of the vehicle further based on the determined direction corresponding to a direction of the first tilting angle, and
wherein the controller estimates the direction of motion of the vehicle based on at least the second yaw rate of the second yaw sensor.

9. The vehicle of claim 1 , further comprising:
an encoder coupled to the platform, wherein the encoder provides an indication of an orientation of the platform in response to the actuator causing the platform to rotate, and wherein the controller determines the rate of rotation of the platform based on output from the encoder.

10. The vehicle of claim 1 , further comprising:
data storage storing calibration data for the yaw sensor, wherein the calibration data is indicative of a mapping between given rates of rotation of the platform and previously measured yaw rates indicated by the yaw sensor, and wherein the controller estimates the direction of motion of the vehicle based also on the calibration data.

11. The vehicle of claim 10 , further comprising an input interface, wherein the controller updates the calibration data in response to receiving a request for calibrating the yaw sensor via the input interface.

12. The vehicle of claim 10 , further comprising a temperature sensor, wherein the calibration data includes an indication of a previously measured temperature indicated by the temperature sensor at a time of receipt of the previously measured yaw rates of the calibration data, and wherein the controller updates the calibration data based on at least the temperature sensor indicating a measured temperature that differs from the previously measured temperature by at least a threshold amount.

13. The vehicle of claim 10 , wherein the controller updates the calibration data based on at least passage of a given amount of time from a time of a previous update to the calibration data.

14. The vehicle of claim 10 , wherein the controller updates the calibration data in response to activation of the vehicle, and wherein activation of the vehicle causes the controller to receive power.

15. A method comprising:
receiving, from a yaw sensor mounted on a platform of a vehicle, an indication of a yaw rate of rotation of the yaw sensor in a first direction relative to a yaw axis of the vehicle;
rotating, by an actuator, the platform at a rate of rotation in a second direction based on the yaw rate of rotation of the yaw sensor, wherein the second direction is opposite to the first direction; and
estimating a change in a direction of the vehicle in an environment based on at least the rate of the rotation of the platform.

16. The method of claim 15 , further comprising:
determining that the vehicle is tilting about a roll axis of the vehicle or a pitch axis of the vehicle, wherein the tilting of the vehicle causes a tilt offset to a yaw axis of the yaw sensor; and
responsively actuating the platform to reduce the tilt offset.

17. A method comprising:
obtaining sensor data collected using a sensor mounted on a platform of a vehicle, wherein the sensor data includes an indication of a rate of change to a direction of the sensor about a reference axis of the sensor in a first direction;
rotating the platform in a second direction such that a rate of the rotation is based on the rate of change to the direction of the sensor, wherein the second direction is opposite to the first direction; and
based on at least the rate of the rotation of the platform, estimating a change in a direction of the vehicle in an environment of the vehicle.

18. The method of claim 17 , further comprising:
accessing stored calibration data associated with the sensor, wherein the stored calibration data maps given rates of rotation of the platform to previously measured rates of change to the direction of the sensor, and wherein estimating the change in the direction of the vehicle is also based on the stored calibration data.

19. The method of claim 17 , further comprising:
enabling a calibration mode of the vehicle, wherein estimating the change in the direction of the vehicle

Assignees

• Waymo Llc

Inventors

• Robinson Craig
• Tisdale John
• Laforge Seth
• Karplus Paul

Classifications

• G01C21/18

  Stabilised platforms, e.g. by gyroscope · CPC title

• B60W40/114 Primary

  Yaw movement · CPC title

• G01C19/34

  for indicating a direction in the horizontal plane, e.g. directional gyroscopes · CPC title

• G01C21/20 Primary

  Instruments for performing navigational calculations (G01C21/24, G01C21/26 take precedence) · CPC title

• B60W2050/0083

  Setting, resetting, calibration · CPC title