Viewing and display apparatus position determination algorithms

• US 7,428,780 B2
• Filed: 01/02/2007
• Issued: 09/30/2008
• Est. Priority Date: 06/04/2004
• Status: Expired due to Fees

• Current Assignee: Yamcon Inc.
• Original Assignee: Yamcon Inc.
• Inventors: Lemp, III, Michael, Hatalski, Michael
• Primary Examiner(s): BENNETT, GEORGE B
• Application Number:
  US11/619,126
• Publication Number:
  US 20070193044A1
• Time in Patent Office: 637 Days
• Field of Search: 332/68, 332/73, 332/81, 333/55.R, 333/661.1, 333/661.2, 340/815.4, 340/999, 434/284, 434/289
• US Class Current: 33/268
• CPC Class Codes: G01C 17/34 Sun- or astro-compasses
• CPC Class Codes: G01C 21/02 by astronomical means G01C21/24, G01C21/26 take precedence

Abstract

Celestial object location devices with sensor arrays of having less that one sensor for each of three orthogonal components of gravity and magnetic field vectors. The accuracy of position sensing is enhanced by estimating “missing” sensor input based on input from two orthogonal sensors provided, or determined with limitations from the two gravitational sensors provided.

Claims

1. A method of viewing celestial objects comprising the steps:

providing a celestial object viewing device having a viewing axis defined by an azimuth angle and a nadir angle, a magnetic field sensor array having a first, second and third magnetic field sensors arranged orthogonally with the first magnetic field sensor aligned parallel to the viewing axis and each magnetic field sensor generating a signal proportional to a sensed magnetic field, a gravitational sensor array having two perpendicular gravity sensors, with a first gravity sensor aligned parallel to the viewing axis and each gravity sensor generating a signal proportional to a sensed gravity field, a microprocessor, a database, and output means;

the microprocessor receiving signals from the magnetic field sensors and the gravity field sensors;

the microprocessor computing an azimuth angle and a nadir angle relative to the viewing axis;

the microprocessor providing data from the database to the output means related to celestial objects aligned with the viewing axis.

2. The method of claim 1 wherein the microprocessor computing step further comprises the steps:

determining a first gravity field component from the first gravity field sensor;

determining a second gravity field component from the gravity field sensor perpendicular to the first gravity field sensor;

computing a third gravity field component using the first and second gravity field components;

computing the nadir angle using the first, second and third gravity field components.

3. The method of claim 1 wherein the microprocessor computing step further comprises the steps:

determining a first magnetic field component from the first magnetic field sensor;

determining a second magnetic field component from the second magnetic field sensor;

determining a third magnetic field component from the third magnetic field sensor;

computing the azimuth angle using the first, second and third magnetic field components.

4. A celestial viewing device comprising:

a housing defining a viewing axis forming an azimuth angle and a nadir angle;

a magnetic sensor array in the housing, the magnetic sensor array having a first, second and third magnetic field sensors arranged orthogonally with the first magnetic field sensor aligned parallel to the viewing axis and each magnetic field sensor operable to produce a magnetic signal proportional to a sensed magnetic field;

a gravitational sensor array in the housing, the gravitational sensor array having two perpendicular gravity sensors, with a first gravity sensor aligned parallel to the viewing axis and each gravity sensor operable to produce a gravity signal proportional to a sensed gravity field;

a database;

output means for presenting data to a user; and

a microprocessor operable to receive the magnetic signals and compute the azimuth angle relative to the viewing axis, and receive the gravity signals and compute the nadir angle relative to the viewing axis, and interact with the database to provide data to the output means related to the viewing axis.

5. The apparatus of claim 4 wherein the microprocessor further comprises:

a microprocessor operable to determine a first gravity field component from the first gravity field sensor signal, and determine a second gravity field component from the gravity signal of the gravity field sensor perpendicular to the first gravity field sensor, and compute a third gravity field component using the first and second gravity field components and compute the nadir angle relative to the viewing axis using the first, second and third gravity field components, receive the magnetic signals and compute the azimuth angle relative to the viewing axis, and interact with the database to provide data to the output means related to the viewing axis.

6. The apparatus of claim 4 wherein the microprocessor further comprises:

a microprocessor operable to determine a first magnetic field component from the first magnetic field sensor, to determine a second magnetic field component from the second magnetic field sensor, to determine a third magnetic field component from the third magnetic field sensor, to compute the azimuth angle using the first, second and third magnetic field components, and receive the gravity signals and compute the nadir angle relative to the viewing axis, and interact with the database to provide data to the output means related to the viewing axis.

7. The apparatus of claim 4 wherein the microprocessor further comprises:

a microprocessor operable to determine a first gravity field component from the first gravity field sensor signal, and determine a second gravity field component from the gravity signal of the gravity field sensor perpendicular to the first gravity field sensor, and compute a third gravity field component using the first and second gravity field components and compute the nadir angle relative to the viewing axis using the first, second and third gravity field components, the microprocessor operable to determine a first magnetic field component from the first magnetic field sensor, to determine a second magnetic field component from the second magnetic field sensor, to determine a third magnetic field component from the third magnetic field sensor, to compute the azimuth angle using the first, second and third magnetic field components, and the microprocessor operable interact with the database to provide data to the output means related to the viewing axis.

8. A method of viewing celestial objects comprising the steps:

providing a celestial object viewing device having a viewing axis defined by an azimuth angle and a nadir angle, a magnetic field sensor array having a first, second and third magnetic field sensors arranged orthogonally with the first magnetic field sensor aligned parallel to the viewing axis and each magnetic field sensor generating a signal proportional to a sensed magnetic field, a gravitational sensor array having two perpendicular gravity sensors, with a first gravity sensor aligned parallel to the viewing axis and each gravity sensor generating a signal proportional to a sensed gravity field, a microprocessor, a database, and output means;

the microprocessor receiving signals from the magnetic field sensors and the gravity field sensors;

the microprocessor computing an azimuth angle and a nadir angle relative to the viewing axis.

9. The method of claim 8 wherein the microprocessor computing step further comprises the steps:

determining a first gravity field component from the first gravity field sensor;

determining a second gravity field component from the gravity field sensor perpendicular to the first gravity field sensor;

computing a third gravity field component using the first and second gravity field components;

computing the nadir angle using the first, second and third gravity field components.

10. The method of claim 8 wherein the microprocessor computing step further comprises the steps:

determining a first magnetic field component from the first magnetic field sensor;

determining a second magnetic field component from the second magnetic field sensor;

determining a third magnetic field component from the third magnetic field sensor;

computing the azimuth angle using the first, second and third magnetic field components.

11. A celestial viewing device comprising:

a housing defining a viewing axis forming an azimuth angle and a nadir angle;

a magnetic sensor array in the housing, the magnetic sensor array having a first, second and third magnetic field sensors arranged orthogonally with the first magnetic field sensor aligned parallel to the viewing axis and each magnetic field sensor operable to produce a magnetic signal proportional to a sensed magnetic field;

a gravitational sensor array in the housing, the gravitational sensor array having two perpendicular gravity sensors, with a first gravity sensor aligned parallel to the viewing axis and each gravity sensor operable to produce a gravity signal proportional to a sensed gravity field;

output means for presenting data to a user; and

a microprocessor operable to receive the magnetic signals and compute the azimuth angle relative to the viewing axis, and receive the gravity signals and compute the nadir angle relative to the viewing axis, and provide data to the output means related to the viewing axis.

12. The apparatus of claim 11 wherein the microprocessor further comprises:

a microprocessor operable to determine a first gravity field component from the first gravity field sensor signal, and determine a second gravity field component from the gravity signal of the gravity field sensor perpendicular to the first gravity field sensor, and compute a third gravity field component using the first and second gravity field components and compute the nadir angle relative to the viewing axis using the first, second and third gravity field components, receive the magnetic signals and compute the azimuth angle relative to the viewing axis, and interact with the database to provide data to the output means related to the viewing axis.

13. The apparatus of claim 11 wherein the microprocessor further comprises:

a microprocessor operable to determine a first magnetic field component from the first magnetic field sensor, to determine a second magnetic field component from the second magnetic field sensor, to determine a third magnetic field component from the third magnetic field sensor, to compute the azimuth angle using the first, second and third magnetic field components, and receive the gravity signals and compute the nadir angle relative to the viewing axis, and interact with the database to provide data to the output means related to the viewing axis.

14. The apparatus of claim 11 wherein the microprocessor further comprises:

a microprocessor operable to determine a first gravity field component from the first gravity field sensor signal, and determine a second gravity field component from the gravity signal of the gravity field sensor perpendicular to the first gravity field sensor, and compute a third gravity field component using the first and second gravity field components and compute the nadir angle relative to the viewing axis using the first, second and third gravity field components, the microprocessor operable to determine a first magnetic field component from the first magnetic field sensor, to determine a second magnetic field component from the second magnetic field sensor, to determine a third magnetic field component from the third magnetic field sensor, to compute the azimuth angle using the first, second and third magnetic field components, and the microprocessor operable interact with the database to provide data to the output means related to the viewing axis.