Methods and systems for calibrating sensors using road map data

• US 9,719,801 B1
• Filed: 07/23/2013
• Issued: 08/01/2017
• Est. Priority Date: 07/23/2013
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Waymo LLC (Alphabet Inc.)
• Inventors: Iordache, Dorel Ionut, Ferguson, Dave
• Primary Examiner(s): Lee, Paul D
• Application Number:
  US13/948,457
• Time in Patent Office: 1,470 Days
• Field of Search: 702 94
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G01C 21/30 Map- or contour-matching
• CPC Class Codes: G01C 21/3602 Input other than that of destination using image analysis, e.g. detection of road signs, lanes, buildings, real preceding vehicles using a camera
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 19/40 Correcting position, velocity or attitude
• CPC Class Codes: G01S 3/781 Details
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 7/484 Transmitters
• CPC Class Codes: G01S 7/4868 Controlling received signal intensity or exposure of sensor
• CPC Class Codes: G01S 7/4972 Alignment of sensor
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: G06V 20/588 Recognition of the road, e.g. of lane markings; Recognition of the vehicle driving pattern in relation to the road

Abstract

Example methods and systems for calibrating sensors using road map data are provided. An autonomous vehicle may use various vehicle sensors to assist in navigation. Within examples, the autonomous vehicle may calibrate vehicle sensors through performing a comparison or analysis between information about the environment received by sensors with similar information provided by map data (e.g., a road map). The autonomous vehicle may compare object locations as provided by the sensors and as shown by map data. Based on the comparison, the autonomous vehicle may adjust various sensors to accurately reflect the information as provided by the road map. In some instances, the autonomous vehicle may adjust the position, height, orientation, direction-of-focus, scaling, or other parameters of a sensor based on the information provided by a road map.

Claims

1. A method comprising:

receiving, via at least one sensor coupled to a vehicle, information indicative of an environment of the vehicle, wherein the information includes measurements of a series of lane markers extending as a lane boundary of a road that the vehicle is traveling;

based on the information indicative of the environment of the vehicle, determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary;

receiving map data that depicts the road that the vehicle is traveling and includes location information for the series of lane markers;

determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary;

performing, as the vehicle travels the road, a comparison to determine differences between the estimated locations of the series of lane markers based on the information from the at least one sensor and the given locations for the series of lane markers determined using the map data; and

based on the differences determined by the comparison, providing instructions to adjust at least one of an orientation or an intensity of the at least one sensor relative to the vehicle.

2. The method of claim 1, wherein the at least one sensor includes one or more of a camera, RADAR, LIDAR, and a global positioning system (GPS).

3. The method of claim 1, wherein determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises:

determining one or more features of the series of lane markers, wherein the one or more features include one or more of a reflective light intensity, a height, a color, a texture; and

wherein determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises using the one or more features.

4. The method of claim 1, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust an intensity level of lasers emitted by the sensor based on differences determined by the comparison.

5. The method of claim 1, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust a position of the sensor based on differences determined by the comparison.

6. The method of claim 1, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust an operation schedule of the sensor based on differences determined by the comparison.

7. A non-transitory computer readable storage medium having stored therein instructions, that when executed by a computing device, cause the computing device to perform functions comprising:

receiving, via at least one sensor coupled to a vehicle, information indicative of an environment of the vehicle, wherein the information includes measurements of a series of lane markers extending as a lane boundary of a road that the vehicle is traveling;

based on the information indicative of the environment of the vehicle, determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary

receiving map data that depicts the road that the vehicle is traveling and includes location information for the series of lane markers;

determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary;

performing, as the vehicle travels the road, a comparison to determine differences between the estimated locations of the series of lane markers based on the information from the at least one sensor and the given locations for the series of lane markers determined using the map data; and

based on the differences determined by the comparison, providing instructions to adjust at least one of an orientation or an intensity of the at least one sensor relative to the vehicle.

8. The non-transitory computer readable storage medium of claim 7, wherein the at least one sensor includes one or more of a camera, RADAR, LIDAR, and a global positioning system (GPS).

9. The non-transitory computer readable storage medium of claim 7, wherein determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises:

determining one or more features of the series of lane markers, wherein the one or more features include one or more of a reflective light intensity, a height, a color, a texture; and

wherein determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises using the one or more features.

10. The non-transitory computer readable storage medium of claim 7, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust an intensity level of lasers emitted by the sensor based on differences determined by the comparison.

11. The non-transitory computer readable storage medium of claim 7, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust a position of the sensor based on differences determined by the comparison.

12. A system, comprising:

at least one processor; and

data storage comprising instructions executable by the at least one processor to cause the system to perform functions comprising;

receiving, via at least one sensor coupled to a vehicle, information indicative of an environment of the vehicle, wherein the information includes measurements of a series of lane markers extending as a lane boundary of a road that the vehicle is traveling;

based on the information indicative of the environment of the vehicle, determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary

receiving map data that depicts the road that the vehicle is traveling and includes location information for the series of lane markers;

determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary;

performing, as the vehicle travels the road, a comparison to determine differences between the estimated locations of the series of lane markers based on the information from the at least one sensor and the given locations for the series of lane markers determined using the map data; and

based on the differences determined by the comparison, providing instructions to adjust at least one of an orientation or an intensity of the at least one sensor relative to the vehicle.

13. The system of claim 12, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust an internal timing mechanism of the sensor based on differences determined by the comparison.

14. The system of claim 12, wherein providing instructions to adjust at least one of the orientation or the intensity of the at least one sensor relative to the vehicle further comprises:

configuring the at least one sensor to adjust a position of the sensor based on differences determined by the comparison.

15. The system of claim 12, wherein determining estimated locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises:

determining one or more features of the series of lane markers, wherein the one or more features include one or more of a reflective light intensity, a height, a color, a texture; and

wherein determining, using the map data, given locations for the series of lane markers relative to the vehicle as the vehicle travels the road according to the lane boundary comprises using the one or more features.

16. The system of claim 12, wherein the at least one sensor includes one or more of a camera, RADAR, LIDAR, and a global positioning system (GPS).