MAPPING TECHNIQUES USING PROBE VEHICLES

• US 20150127239A1
• Filed: 12/15/2014
• Published: 05/07/2015
• Est. Priority Date: 11/01/2013
• Status: Active Grant

• Current Assignee: Intelligent Technologies International, Inc.
• Original Assignee: Intelligent Technologies International, Inc.
• Inventors: Breed, David S., Breed, Ryan
• Granted Patent: US 9,528,834 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• 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: G01C 21/1652 with ranging devices, e.g. LIDAR or RADAR
• CPC Class Codes: G01C 21/1656 with passive imaging devices, e.g. cameras
• CPC Class Codes: G01S 19/13 Receivers
• CPC Class Codes: G06T 2207/10004 Still image; Photographic image
• CPC Class Codes: G06T 2207/30244 Camera pose
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/73 using feature-based methods

Abstract

Vehicle-mounted device includes an inertial measurement unit (IMU) having at least one accelerometer or gyroscope, a GPS receiver, a camera positioned to obtain unobstructed images of an area exterior of the vehicle and a control system coupled to these components. The control system re-calibrates each accelerometer or gyroscope using signals obtained by the GPS receiver, and derives information about objects in the images obtained by the camera and location of the objects based on data from the IMU and GPS receiver. A communication system communicates the information derived by the control system to a location separate and apart from the vehicle. The control system includes a processor that provides a location of the camera and a direction in which the camera is imaging based on data from the IMU corrected based on data from the GPS receiver, for use in creating the map database.

Claims

1. A vehicle-mounted device, comprising:

an inertial measurement unit (IMU) comprising at least one accelerometer or gyroscope;

a GPS receiver;

a camera positioned to obtain unobstructed images of an area exterior of the vehicle;

a control system coupled to said IMU, said GPS receiver and said camera, said control system being configured to re-calibrate said at least one accelerometer or gyroscope using signals obtained by said GPS receiver, said control system deriving information about objects in the images obtained by said camera and location of the objects based on data from said IMU and said GPS receiver; and

a communication system coupled to said control system and that communicates the information derived by said control system to a location separate and apart from the vehicle,

wherein said control system including a processor is configured to provide a location of said camera and a direction in which said camera is imaging based on data from said IMU corrected based on data from said GPS receiver.

2. The device of claim 1, wherein said IMU is manufactured using mass-production MEMS technology.

3. The device of claim 1, wherein said control system is further configured to re-calibrate said at least one accelerometer or gyroscope using a zero lateral and vertical speed of the vehicle and speedometer and odometer readings of the vehicle.

4. The device of claim 1, wherein said control system is further configured to correct projections of gravitational acceleration in accelerometer readings from said at least one accelerometer, when the vehicle tilts, and projections of centrifugal accelerations in readings from said at least one gyroscope during turning maneuvers.

5. The device of claim 1, wherein said IMU, said GPS receiver, said camera, said control system and said communication system are mounted in a single housing, said housing being position on the vehicle such that said camera images a portion of a road in front of the vehicle and terrain on both sides of the vehicle, said camera having a horizontal field of view of from about 45 to about 180 degrees.

6. The device of claim 1, further comprising a speed limiting apparatus that notifies a driver of the vehicle of a maximum speed of travel of the vehicle or automatically limits speed of the vehicle to the maximum speed of travel of the vehicle, said control system being coupled to said speed limiting apparatus and generating the maximum speed of travel of the vehicle based on speed and accuracy of processing of images obtained by said camera by said control system.

7. The device of claim 1, further comprising a map database resident on the vehicle, said map database including location of objects in the images obtained by said camera.

8. The device of claim 7, wherein said control system is further configured to identify objects in images obtained by said camera and their location and determine whether the objects are present in the map database, said processor being configured to communicate information about an object derived by said control system to the location separate and apart from the vehicle only when the object is not present in said map database.

9. The device of claim 7, wherein said control system is configured to correct data from said IMU using said map database and said camera and without use of data from said GPS receiver by comparing expected position of an object in an image obtained by said camera when the vehicle is at a specific position using said map database to actual position of the same object in an image obtained by said camera as determined by said processor when the vehicle when at the specific position, and correcting the data from said IMU when the actual vehicle position differs from the expected vehicle position.

10. The device of claim 1, wherein said communication system communicates location of the vehicle to the remote location, and said camera is configured to be controllable by said remote station to obtain images based on its location communicated by said communication system.

11. A method for mapping terrain, comprising:

obtaining information about objects using one or more devices each comprising an inertial measurement unit (IMU) including at least one accelerometer or gyroscope, a GPS receiver, a camera positioned to obtain unobstructed images of an area exterior of the device, and a control system coupled to the IMU, the GPS receiver and the camera;

re-calibrating the at least one accelerometer or gyroscope using signals obtained by the GPS receiver;

deriving information about objects in the images obtained by the camera and location of the objects based on data from the IMU and the GPS receiver;

transmitting the information derived by the control system of each device to a location separate and apart from the vehicle using a communications system co-located with the device; and

correcting the data from the IMU using data from the GPS receiver, using a processor of the control system, to provide a position of the camera of each device when each image is obtained and a pointing direction of the camera when each image is obtained.

12. The method of claim 11, further comprising maintaining a map database by adding to the map database, objects in images obtained by the camera, the map database maintaining step comprising:

identifying the same object in two or more images obtained from different locations using the processor; and

positioning, using the processor, the object in the map database based on the data about the location from which the two or more images were obtained and the pointing direction of the camera on the device when the images were obtained.

13. The method of claim 12, further comprising:

identifying objects in images obtained by the camera and their location using the processor;

determining whether the identified objects are present in the map database using the processor; and

controlling, using the processor, transmission of information from the device to the location separate and apart from the vehicle using the communications system such that derived information about an object is transmitted to the location separate and apart from the vehicle only when the object is not present in the map database.

14. The method of claim 12, further comprising:

correcting, using the processor, data from the IMU using the map database and the camera and without use of data from the GPS receiver by comparing expected position of an object in an image obtained by the camera when the vehicle is at a specific position known from the map database to actual position of the same object in an image obtained by the camera as determined by the processor when the vehicle when at the specific position, and correcting the data from the IMU when the actual vehicle position differs from the expected vehicle position.

15. A method for obtaining position information about a vehicle, comprising:

obtaining a plurality of images including a common object using a camera on the vehicle;

accessing a map database on the vehicle to obtain an expected location of the vehicle based on a known location of the object in the map database and a relationship between location of the vehicle when the images were obtained and the object, the relationship between location of the vehicle when the images were obtained and the object being derived from information from an inertial measurement unit (IMU) comprising at least one accelerator or gyroscope; and

correcting, using a processor, data from the IMU using the map database and the camera and without use of data from a GPS receiver by comparing expected position of the object in the images obtained by the camera when the vehicle is at a specific position known from the map database to actual position of the same object in an image obtained by the camera as determined by the processor when the vehicle when at the specific position, and correcting the data from the IMU when the actual vehicle position differs from the expected vehicle position.