Systems and methods for sensor drift compensation

Patent metadata

Field	Value
Publication number	US-9804050-B2
Application number	US-201414211623-A
Country	US
Kind code	B2
Filing date	Mar 14, 2014
Priority date	Mar 14, 2013
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

An exemplary embodiment of the present invention provides systems and methods of compensating sensor drift. In one example embodiment, a system may comprise a primary sensor having a primary full-scale range and configured to output a primary environmental condition signal indicative of an environmental condition; a reference sensor having a reference full-scale range and configured to output a reference environmental condition signal indicative of the environmental condition, wherein the reference full-scale range is less than the primary full-scale range; and a drift compensation system configured to determine a drift compensation signal using the primary environmental signal and the reference environmental condition signal responsive to the reference environmental conditional signal being in the reference full-scale range and compensate the primary environmental condition signal using the drift compensation signal.

First claim

What is claimed is:

1. A system, comprising:
a primary sensor having a primary full-scale range and configured to output a primary environmental condition signal indicative of an environmental condition;
a reference sensor having a reference full-scale range and configured to output a reference environmental condition signal indicative of the environmental condition, wherein the reference full-scale range is less than the primary full-scale range; and
a drift compensation system comprising:
a comparator configured to:
determine a first condition if a first value of the reference environment condition signal is within the reference full-scale range, and
determine a second condition if a second value of the reference environment condition signal is greater than the reference full-scale range;

counter circuitry configured to:
iteratively generate a first condition-dependent compensation signal responsive to the determined first condition, wherein the first condition-dependent compensation signal is summed with the primary environmental condition signal to produce a drift-compensated output that iteratively tracks the reference environmental condition signal; and
generate a second condition-dependent compensation signal responsive to the determined second condition, wherein the second condition-dependent compensation signal is summed with the primary environmental condition signal to produce the drift-compensated output, wherein the second condition-dependent compensation signal comprises an offset value, wherein the offset value is determined based on a difference between a threshold primary environmental condition signal and a threshold reference environmental condition signal, wherein the threshold signals are determined based on the reference environmental condition signal being substantially equal to the reference full-scale range.

2. The system of claim 1 , wherein the drift compensation system further comprises a controllable oscillator in communication with the counter circuitry, wherein the drift compensation system is further configured to iteratively compensate the primary environmental condition signal so that the drift-compensated output is substantially equivalent to the reference environmental condition signal over the reference full-scale range.

3. The system of claim 1 , wherein the drift compensation system is further configured to increase the second condition-dependent compensation signal responsive to the drift-compensated output signal being greater than the reference environmental condition signal.

4. The system of claim 1 , wherein the drift compensation system is further configured to combine the primary environmental condition signal and the first condition-dependent compensation signal responsive to the reference environmental condition signal being in the reference full-scale range.

5. The system of claim 1 , wherein the reference full-scale range is less than about ten percent (10%) of the primary full-scale range.

6. The system of claim 1 , wherein each of the primary sensor and the reference sensor is a pressure sensor.

7. The system of claim 1 , wherein each of the primary sensor and the reference sensor is a temperature sensor.

8. The system of claim 1 , wherein the primary sensor and the reference sensor are co-located.

9. A method, comprising:
outputting, by a primary sensor having a primary full-scale range, a primary environmental condition signal indicative of an environmental condition;
outputting, by a reference sensor having a reference full-scale range, a reference environmental condition signal indicative of the environmental condition, wherein the reference full-scale range is within the primary full-scale range;
determining a first condition if a first value of the reference environment condition signal is within the reference full-scale range, and iteratively generating a first condition-dependent compensation signal responsive to the determined first condition, wherein the first condition-dependent compensation signal is summed with the primary environmental condition signal to produce a drift-compensated output that iteratively tracks the reference environmental condition signal; and
determining a second condition if a second value of the reference environment condition signal is greater than the reference full-scale range, and generating a second condition-dependent compensation signal responsive to the determined second condition, wherein the second condition-dependent compensation signal is summed with the primary environmental condition signal to produce the drift-compensated output, wherein the second condition-dependent compensation signal comprises an offset value, wherein the offset value is determined based on a difference between a threshold primary environmental condition signal and a threshold reference environmental condition signal, wherein the threshold signals are determined based on the reference environmental condition signal being substantially equal to the reference full-scale range.

10. The method of claim 9 , wherein compensating the primary environmental condition signal includes iteratively modifying the drift-compensated output signal to be substantially equivalent to the reference environmental condition signal over the reference full-scale range.

11. The method of claim 9 , wherein the second condition-dependent compensation signal is increased responsive to the drift-compensated output signal being greater than the reference environmental condition signal.

12. The method of claim 9 , wherein the primary environmental condition signal and the first condition-dependent compensation signal are combined responsive to the reference environmental condition signal being in the reference full-scale range.

13. The method of claim 9 , wherein the reference full-scale range is less than about ten percent (10%) of the primary full-scale range.

14. The method of claim 9 , wherein each of the primary sensor and the reference sensor is a pressure sensor.

15. The method of claim 9 , wherein each of the primary sensor and the reference sensor is a temperature sensor.

16. The method of claim 9 , wherein the primary sensor and the reference sensor are co-located.

Assignees

• Landmann Wolf S
• Kulite Semiconductor Products Inc

Inventors

• Landmann Wolf S

Classifications

• G01K15/005

  Calibration · CPC title

• G01L27/005 Primary

  Apparatus for calibrating pressure sensors · CPC title

• G01K1/20

  Compensating for effects of temperature changes other than those to be measured, e.g. changes in ambient temperature · CPC title