Environmental characteristic determination

• US 20060253253A1
• Filed: 05/09/2005
• Published: 11/09/2006
• Est. Priority Date: 05/09/2005
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Litton Systems Incorporated
• Inventors: Perlmutter, Michael, Humphrey, Ian, Heckathorn, Donald, Reynolds, Christopher I.
• Granted Patent: US 7,650,238 B2
• Time in Patent Office: Days
• US Class Current: 701/220
• CPC Class Codes: G01C 21/166 Mechanical, construction or arrangement details of inertial navigation systems
• CPC Class Codes: G01P 15/08 with conversion into electric or magnetic values
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups

Abstract

A processor of an apparatus in one example makes a determination of an environmental characteristic based on an average of a plurality of concomitant values that correspond to the environmental characteristic.

Claims

1. An apparatus, comprising:

plurality of concomitant values indicative of an environmental characteristic; and

a processor having a plurality of inputs for receiving the plurality of concomitant values and having an output that provides a determination of the environmental characteristic;

wherein the processor determines the environmental characteristic based on a combination of the plurality of concomitant values.

2. The apparatus of claim 1, further comprising:

a plurality of sensors that obtain the plurality of concomitant values that correspond to the environmental characteristic; and

each of the plurality of sensors having an output operatively coupled to a respective input of the processor.

3. The apparatus of claim 2, wherein the plurality of sensors comprise independent sensors of the environmental characteristic.

4. The apparatus of claim 2, wherein the processor determines an average of the plurality of concomitant values in order to reduce error terms in the plurality of concomitant values.

5. The apparatus of claim 2, wherein the plurality of sensors comprise at least one gyroscope and at least one accelerometer.

6. The apparatus of claim 5, wherein the gyroscope is a Micro-Electro-Mechanical Systems gyroscope.

7. The apparatus of claim 5, wherein the accelerometer is a Micro-Electro-Mechanical Systems accelerometer.

8. The apparatus of claim 2, wherein the processor multiplies each of the plurality of concomitant values by at least one weighting value to determine a weighted average of the plurality of concomitant values.

9. The apparatus of claim 1, wherein the determination of the environmental characteristic comprises a determination of the environmental characteristic for a pre-determined time period;

wherein the plurality of concomitant values comprise a plurality of concomitant values from the pre-determined time period.

10. The apparatus of claim 1, wherein the combination is an average of the plurality of concomitant values and wherein the average comprises a summation value divided by a scaling value;

and

wherein the summation value comprises a summation of the plurality of concomitant values, wherein the scaling value comprises a number of the plurality of concomitant values multiplied by a scaling factor.

11. The apparatus of claim 1, wherein the environmental characteristic comprises at least one of angular rate, angular acceleration, temperature, pressure, strain, electrical field strength, and magnetic field strength.

12. A method, comprising:

determining, via a plurality of independent electronic sensors, a plurality of independent, concomitant values indicative of an environmental characteristic;

calculating, via a processor, an average of the plurality of independent, concomitant values of the environmental characteristic; and

providing the average of the plurality of independent, concomitant values as a single value indicative of the environmental characteristic.

13. The method of claim 12, wherein the plurality of independent electronic sensors comprise at least one of gyroscopes and accelerometers.

14. The method of claim 12, wherein the plurality of independent electronic sensors comprise at least one of single-axis and/or multi-axis gyroscopes.

15. The method of claim 12, wherein the processor performs at least one of an analog-to-digital conversion and a digital-to-analog conversion on at least one of the plurality of independent, concomitant values before a determination of the average of the plurality of independent, concomitant values.

16. The method of claim 15, wherein the environmental characteristic comprises at least one of an angular rate and angular acceleration;

wherein the processor provides the single value for the at least one of the angular rate and the angular acceleration to a navigation, control, and inertial guidance system.

17. An inertial measurement unit that provides a pitch angular rate measurement, a roll angular rate measurement, and a yaw angular rate measurement, comprising:

a pitch circuit that comprises a pitch processor and a plurality of independent pitch sensors;

a roll circuit that comprises a roll processor and a plurality of independent roll sensors; and

a yaw circuit that comprises a yaw processor and a plurality of independent yaw sensors;

wherein the pitch processor receives a plurality of concomitant pitch values from the plurality of independent pitch sensors;

wherein the pitch processor determines an average of the concomitant pitch values;

wherein the roll processor receives a plurality of concomitant roll values from the plurality of independent roll sensors;

wherein the roll processor determines an average of the concomitant roll values;

wherein the yaw processor receives a plurality of concomitant yaw values from the plurality of independent yaw sensors;

wherein the yaw processor determines an average of the concomitant yaw values;

wherein the inertial measurement unit provides the average of the concomitant pitch values as the pitch angular rate measurement;

wherein the inertial measurement unit provides the average of the concomitant roll values as the roll angular rate measurement;

wherein the inertial measurement unit provides the average of the concomitant yaw values as the yaw angular rate measurement.

18. The inertial measurement unit of claim 17, wherein the pitch processor determines a weighted average of the concomitant pitch values;

wherein the roll processor determines a weighted average of the concomitant roll values;

wherein the yaw processor determines a weighted average of the concomitant yaw values.

19. The inertial measurement unit of claim 17, wherein each average of the plurality of concomitant values comprises a summation value divided by a scaling value;

wherein the summation value comprises a summation of the plurality of concomitant values, wherein the scaling value comprises a number of the plurality of concomitant values multiplied by a scaling factor.

20. The inertial measurement unit of claim 17, wherein at least one of the plurality of independent pitch sensors, the plurality of independent roll sensors, and the plurality of independent yaw sensors comprise at least one Micro-Electro-Mechanical Systems gyroscope.

21. The inertial measurement unit of claim 17, wherein at least one of the plurality of independent pitch sensors, the plurality of independent roll sensors, and the plurality of independent yaw sensors comprise at least one Micro-Electro-Mechanical Systems accelerometer.

22. The inertial measurement unit of claim 17, wherein the inertial measurement unit provides the pitch angular rate measurement, the roll angular rate measurement, and the yaw angular rate measurement for at least one of a navigation, control, and inertial guidance system.