Apparatus for correcting position and attitude information of camera and method thereof

• US 20060146136A1
• Filed: 11/21/2005
• Published: 07/06/2006
• Est. Priority Date: 12/21/2004
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Cho, Seong-Ik
• Granted Patent: US 7,908,106 B2
• Time in Patent Office: Days
• US Class Current: 348/207.100
• CPC Class Codes: G01S 19/40 Correcting position, velocity or attitude
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 19/485 whereby the further system is an optical system or imaging system
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves

Abstract

Provided is an apparatus for precisely correcting position and attitude information of a camera by analyzing image information received through a three line scanner in operation of the camera obtaining the position and attitude information from a Global Navigation Satellite System (GNSS) and an Inertial Navigation System (INS), and a method thereof. The method for correcting position and attitude information of a camera includes the steps of: a) calculating the position of the camera by using the GNSS; b) calculating the attitude of the camera by using the INS; c) generating the position and attitude correction information of the camera by analyzing an image received through a three line scanner mounted in the camera; and d) receiving a feedback of the position and attitude correction information in the GNSS and the INS.

Claims

1. A method for correcting position and attitude information of a camera, comprising the steps of:

a) calculating the position of the camera by using a Global Navigation Satellite System (GNSS);

b) calculating the attitude of the camera by using an Inertial Navigation System (INS);

c) generating the position and attitude correction information of the camera by analyzing an image received through a three line scanner mounted in the camera; and

d) feeding back the position and attitude correction information in the GNSS and the INS.

2. The method as recited in claim 1, wherein the image received through the three line scanner includes a forward scanner observation image, a nadir scanner observation image, and a backward scanner observation image in the step c).

3. The method as recited in claim 2, wherein the step c) includes the steps of:

c1) calculating a first image position deviation by matching the forward scanner observation image and the nadir scanner observation image; and

c2) calculating a second image position deviation by matching the forward scanner observation image and the nadir scanner observation image.

4. The method as recited in claim 3, wherein the step c) further includes the step of:

c3) applying a time point when the forward scanner observation image is generated, a time point when the nadir scanner observation image is generated, a time point when the backward scanner observation image is generated, the first and second image position deviation, and the position and attitude information of the camera in a time point when the nadir scanner observation image is generated, to a Kalman filter.

5. The method as recited in claim 3, wherein the image position deviation is calculated in a pixel unit.

6. The method as recited in claim 1, wherein precision of the position and attitude information of the camera is controlled by using an onboard processing approach method or a post processing approach method.

7. An apparatus for correcting position and attitude information, comprising:

a camera connected to which the Global Navigation Satellite System (GNSS) and the Inertial Navigation System (INS) and receiving an image, wherein the position and attitude information correction apparatus generates the position and attitude correction information of the camera by analyzing the image received through a three line scanner equipped in the camera, and improves the precision of the position and attitude information of the camera by receiving a feedback of the position and attitude correction information in the GNSS and the INS.

8. The apparatus as recited in claim 7, wherein the three line scanner includes:

a nadir scanner toward a right angle direction from a propagation direction of the observation apparatus mounting the camera;

a forward scanner toward the propagation direction of the observation apparatus; and

a backward scanner toward a direction opposite to the propagation direction of the observation apparatus,

wherein an angle between the nadir scanner and the forward scanner and an angle between the nadir scanner and the backward scanner are less than 90 degree.

9. The apparatus as recited in claim 8, further comprising:

an image matching means for matching an observation image of the forward scanner, which is stored in a first buffer memory, and an image received by real-time observation through the nadir scanner and matching an observation image of the backward scanner, which is stored in a second buffer memory, and an image received by real-time observation through the nadir scanner.

10. The apparatus as recited in claim 9, further comprising:

a Kalman filter processing means for generating the position and attitude correction information by applying the pixel-based image position deviation calculated in the image matching result to the Kalman filter.

11. The apparatus as recited in claim 10, wherein the Kalman filter processing means includes:

a projection transforming means for outputting a real deviation by projecting and transforming the position and attitude information of the camera, in a time point when the observation image of the nadir scanner is generated, into the image position deviation information;

a Kalman filter for computing the camera position and attitude information at a time point when the observation image of the nadir scanner is generated and an estimate with respect to the position and attitude deviation optimized from the real world position deviation; and

a deviation correcting means for calculating the estimated position and attitude correction information, which is optimized at an arbitrary time between a time point when the observation image of the forward scanner is generated and a time point when the observation image of the backward scanner is generated.

12. The apparatus as recited in claim 8, wherein the observation apparatus is one of a satellite, an aircraft and a vehicle.