Center of gravity determination

• US 9,417,151 B2
• Filed: 11/28/2011
• Issued: 08/16/2016
• Est. Priority Date: 11/28/2011
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Fordice, Robert D., Wright, Daniel J., Morris, Donald G., Fabro, Nathan A.
• Primary Examiner(s): Toatley, Gregory J
• Assistant Examiner(s): Suarez, Felix
• Application Number:
  US13/305,240
• Publication Number:
  US 20130138376A1
• Time in Patent Office: 1,723 Days
• Field of Search: 702/87, 702/97, 702/141, 702/150, 702/152, 702/155, 702/156, 702/159, 382/107, 700/275, 701/36
• US Class Current: 1/1
• CPC Class Codes: G01M 1/122 Determining position of centre of gravity

Abstract

In one embodiment a method to determine a center of gravity of a three dimensional object comprises positioning the object on a test platform in a first orientation, determining a position of the center of gravity along a first axis and a second axis when the object is in the first orientation, rotating the object with respect to a third axis which is orthogonal to the first axis and the second axis, determining a position of the center of gravity along at least one of the first axis or the second axis when the object is in the second orientation, and using a change in the position of the center of gravity along the at least one of the first axis or the second axis when the object is in the second orientation to determine a position of the center of gravity along the third axis. Other embodiments may be described.

Claims

1. A method comprising:

positioning an object on a test platform in a first orientation while the test platform is in a first platform position, wherein the test platform is configured with a hoist coupled to a motor to rotate the test platform via a hinge assembly;

determining a first position of a center of gravity of the object along a first axis when the object is in the first orientation, wherein the first axis is orthogonal to a second axis;

using the hoist coupled to the motor to rotate the test platform about the second axis by an angle to position the object in a second orientation, wherein the first orientation is distinct from the second orientation, and wherein the angle is selected independent of the first position and the first platform position;

determining a second position of the center of gravity along the first axis when the object is in the second orientation; and

determining a third position of the center of gravity along a third axis based on the first position and the second position, wherein the third axis is orthogonal to the first axis and the second axis.

2. The method of claim 1, wherein the test platform is oriented substantially parallel to a ground surface when the object is in the first orientation.

3. The method of claim 1, wherein the test platform is oriented at a second angle with respect to a ground surface when the object is in the first orientation.

4. The method of claim 1, wherein determining the first position comprises:

receiving load data from three load cells coupled to the test platform; and

determining the first position based on the load data.

5. The method of claim 1, wherein the angle is between 2 degrees and 15 degrees.

6. The method of claim 1, wherein the first axis, the second axis, and the third axis are axes of an orthogonal coordinate system.

7. The method of claim 1, further comprising determining a platform center of gravity of the test platform in three-dimensional space in the first orientation and the second orientation, wherein the third position is determined based on the platform center of gravity.

8. A system comprising:

a frame;

a test platform coupled to the frame, wherein the test platform is configured to mount an object, wherein the test platform is configured with a hoist coupled to a motor to rotate the test platform via a hinge assembly about a first axis between a first platform position in which the object is in a first orientation and a second platform position in which the object is in a second orientation, wherein the first orientation is distinct from the second orientation, and wherein the first axis is orthogonal to a second axis and a third axis;

three load cells coupled to the frame, wherein the three load cells are configured to collect load data related to the object when the object is mounted on the test platform; and

a processing device coupled to the three load cells and comprising logic instruction stored in a non-transitory computer readable medium which, when executed by the processing device, causes the processing device to;

receive a first data set from the three load cells when the object is in the first orientation;

determine a first position of a center of gravity of the object along the second axis when the object is in the first orientation;

rotate the test platform by an angle to position the object in the second orientation, wherein the angle is selected independent of the first position and the first platform position;

receive a second data set from the three load cells when the object is in the second orientation;

determine a second position of the center of gravity along the second axis when the object is in the second orientation; and

determine a third position of the center of gravity along the third axis based on the first position and the second position.

9. The system of claim 8, wherein the object is oriented substantially parallel to a ground surface when the object is in the first orientation.

10. The system of claim 8, wherein the object is oriented at a second angle with respect to a ground surface when the object is in the first orientation.

11. The system of claim 8, wherein the angle is between 2 degrees and 15 degrees.

12. The system of claim 8, wherein the first axis, the second axis, and the third axis are axes of an orthogonal coordinate system.

13. The system of claim 8, wherein the processing device further comprises logic instruction stored in the non-transitory computer readable medium which, when executed by the processing device, configures the processing device to determine a platform center of gravity of the test platform in three-dimensional space in the first orientation and the second orientation, wherein the third position is further determined based on the platform center of gravity.

14. A computer-based system comprising:

a non-transitory memory module;

a computer-based processing device coupled to the non-transitory memory module; and

logic instruction stored in the non-transitory memory module which, when executed by the computer-based processing device, configures the computer-based processing device to;

receive a first data set from three load cells coupled to a test platform holding an object in a first orientation while the test platform is in a first platform position, wherein the test platform is configured with a hoist coupled to a motor to rotate the test platform via a hinge assembly;

determine a first position of a center of gravity of the object along a first axis in three dimensional space when the object is in the first orientation, wherein the first axis is orthogonal to a second axis;

cause the hoist coupled to the motor to rotate the test platform to rotate the object about the second axis by an angle to position the object in a second orientation, wherein the angle is selected independent of the first position and the first platform position, and wherein the first orientation is distinct from the second orientation;

receive a second data set from the three load cells when the object is positioned on the test platform in the second orientation;

determine a second position of the center of gravity along the first axis when the object is in the second orientation; and

determine a third position of the center of gravity along a third axis based on the first position and the second position, wherein the third axis is orthogonal to the first axis.

15. The computer-based system of claim 14, wherein the object is oriented substantially parallel to a ground surface when the object is in the first orientation.

16. The computer-based system of claim 14, wherein the object is oriented at a second angle with respect to a ground surface when the object is in the first orientation.

17. The computer-based system of claim 14, wherein the angle is between 2 degrees and 15 degrees.

18. The computer-based system of claim 14, wherein the first axis, the second axis, and the third axis are axes of an orthogonal coordinate system.

19. The computer-based system of claim 14, further comprising logic instructions which, when executed by the computer-based processing device, configures the computer-based processing device to determine a platform center of gravity of the test platform in three-dimensional space in the first orientation and the second orientation, wherein the third position is further determined based on the platform center Of gravity.