Multi-sense environmental monitoring device and method

• US 9,000,910 B2
• Filed: 06/24/2011
• Issued: 04/07/2015
• Est. Priority Date: 06/25/2010
• Status: Active Grant

• Current Assignee: Industrial Scientific Corporation (Fortive Corp.)
• Original Assignee: Industrial Scientific Corporation (Fortive Corp.)
• Inventors: Arunachalam, Raghu
• Primary Examiner(s): Lim, Steven
• Assistant Examiner(s): Fan, Hongmin
• Application Number:
  US13/168,577
• Publication Number:
  US 20110316699A1
• Time in Patent Office: 1,383 Days
• Field of Search: 340/540, 340/521, 340/517, 340/539.26, 340/539.11, 340/632, 702/19, 250/388
• US Class Current: 340/517
• CPC Class Codes: G01N 33/0006 Calibrating gas analysers
• CPC Class Codes: G01N 33/0031 comprising two or more sensors, e.g. a sensor array electrochemical electrode arrays G01N27/27
• CPC Class Codes: G01N 33/0063 using a threshold to release an alarm or displaying means alarm arrangements G08B, e.g. fire alarm actuated by the presence of smoke or gases G08B17/10, for other abnormal conditions G08B21/00
• CPC Class Codes: G08B 21/14 Toxic gas alarms G08B21/16 takes precedence
• CPC Class Codes: G08B 21/16 Combustible gas alarms
• CPC Class Codes: G08B 21/182 Level alarms, e.g. alarms responsive to variables exceeding a threshold
• CPC Class Codes: G08B 29/16 Security signalling or alarm systems, e.g. redundant systems
• CPC Class Codes: G08B 29/24 Self-calibration, e.g. compensating for environmental drift or ageing of components
• CPC Class Codes: G08B 29/26 by updating and storing reference thresholds
• CPC Class Codes: G08B 5/22 using electric transmission; using electromagnetic transmission

Abstract

An environmental monitoring device for detecting and warning users of unhealthy levels of a given substance is disclosed having more than one sensor for each substance to be detected. Each sensor for each substance detected may be positioned in more than one plane or surface on the device. The device may be capable of auto or self calibration. Methods for reading substance levels and auto calibrating are also disclosed.

Claims

1. A monitoring device for monitoring substances, said monitoring device comprising:

a group of at least two sensors, each of the at least two sensors being configured to detect a same substance separately from all other sensors of said device and to generate an output signal in response to a detection of said same substance;

a processing unit operably coupled to the at least two sensors, said processing unit being configured to;

receive each of the output signals from the at least two sensors,

determine a detection signal for said same substance based on the output signals, and

generate a calibration action responsive to at least two of the output signals deviating by a threshold amount, the calibration action comprising at least one of performing self-calibration and generating a calibration request;

a display operably coupled to said processing unit, said display being configured to show a detection condition for said same substance in accordance with said detection signal;

an alarm operably coupled to said processing unit, said alarm being configured to be activated responsive to said detection signal deviating from a level that corresponds to a predetermined concentration of said same substance; and

an orientation sensor operably coupled to said processing unit and configured to provide an orientation output signal indicating the physical orientation of the monitoring device, wherein said processing unit is configured to determine a sensor orientation of each of the at least two sensors based on the orientation output signal and to adjust a concentration reading of at least one of the at least two sensors based on the sensor orientation to determine the detection signal.

2. The monitoring device of claim 1, wherein the at least two sensors of said group of sensors are positioned in more than one plane or surface of the device, thereby reducing a potential failure of the device to monitor for the same substance by preventing simultaneous failure of the at least two sensors due to a physical event.

3. The monitoring device of claim 1, further comprising a user interface configured to provide control signals to said processing unit, the user interface comprising at least one of a button, key, or touch screen.

4. The monitoring device of claim 1, wherein the alarm comprises at least one of a vibration alarm, a visual alarm, and an audio alarm.

5. The monitoring device of claim 1, further comprising a user panic button that controls the alarm.

6. The monitoring device of claim 1, wherein the processing unit is configured to determine a display reading based on a respective concentration detected by each of the at least two sensors in said group.

7. The monitoring device of claim 1, wherein the calibration action comprises self-calibration by adjusting a gain of a sensor to minimize variance among the sensors for the substance.

8. The monitoring device of claim 1, wherein said processing unit is configured to determine a gain of a majority of sensors,

wherein the calibration action comprises self-calibration by adjusting a gain of a deviating sensor to correspond with the gain of the majority of sensors.

9. The monitoring device of claim 1, wherein the sensors of said group are connected to the processing unit through a wired or wireless connection.

10. The monitoring device of claim 1 wherein said processing unit determines said detection signal in accordance with a process selected from the group comprising:

maximum, minimum, arithmetic, mean, median or artificial intelligence logic processes.

11. The monitoring device of claim 10 wherein said processing unit further determines said detection signal in response to at least one factor selected from the group including historic sensor data, span reserve of the respective sensors, gain of the respective sensors, or ambient temperature.

12. The monitoring device of claim 11 wherein said processing unit determines said detection signal according to the relationship:

13. The monitoring device of claim 1 wherein the processing unit is configured to determine a difference between signals from two or more sensors of said group and to generate a sensor fail signal responsive to the difference being above a threshold amount to indicate that a deviating sensor has failed.

14. A method for monitoring a substance using a monitoring device operably coupled with a group of at least two sensors, wherein each of the at least two sensors in said group is configured to detect the same substance, the method comprising the steps of, by a processor:

detecting a concentration of the substance based on output signals from each of the at least two sensors comprising concentration information associated with detection of the same substance;

calculating a display reading of the substance, said display reading being determined based on an aggregate of the output signals;

generating a calibration action responsive to the output signals deviating by a threshold amount, the calibration action comprising at least one of performing self-calibration and generating a calibration request;

comparing the display reading to a threshold limit;

actuating an alarm in response to the display reading deviating from the threshold limit by a predetermined value;

receiving device orientation information from an orientation sensor configured to signify a physical orientation of the monitoring device; and

determining a sensor orientation of the at least two sensors based on the physical orientation of the monitoring device,

wherein calculating the display reading of the substance further comprises compensating said display reading based on the sensor orientation of the at least two sensors.

15. The method of claim 14, wherein the step of calculating the display reading of the substance comprises determining a maximum reading detected by each of the at least two sensors.

16. The method of claim 14, wherein the step of calculating the display reading of the substance comprises determining a minimum reading detected by each of the at least two sensors.

17. The method of claim 14, wherein the step of calculating the display reading of the substance comprises determining the average or weighted average of the respective readings that are detected by the at least two sensors.

18. The method of claim 14, further comprising determining a gain of a majority of sensors, wherein the calibration action comprises self-calibration by adjusting a gain of a deviating sensor to correspond with the gain of the majority of sensors.

19. The method of claim 18, wherein the calibration action comprises self-calibration by adjusting a gain of a deviating sensor to minimize variance among the at least two sensors.

33. The method of claim 14, wherein the at least two sensors are arranged in a network.

34. The method of claim 14, wherein at least one of the at least two sensors are remotely located from the monitoring device.

35. The method of claim 14, wherein the monitoring device is operably coupled with at least one of the at least two sensors via a network connection.

36. The method of claim 35, wherein the network connection comprises at least one of a wired network connection and a wireless network connection.

37. The method of claim 35, wherein the network connection comprises a wireless network connection.

20. A monitoring device for monitoring substances, said monitoring device comprising:

a group of at least two sensors, each of the at least two sensors being configured to detect a same substance separately from all other sensors of said device and to generate an output signal in response to a detection of said same substance;

a processing unit operably coupled to the at least two sensors, said processing unit being configured to;

receive each of the output signals from the at least two sensors,

determine a detection signal for said same substance based on the output signals, and

generate a calibration action responsive to at least two of the output signals deviating by a threshold amount, the calibration action comprising at least one of performing self-calibration and generating a calibration request;

a display operably coupled to said processing unit, said display being configured to show a detection condition for said same substance in accordance with said detection signal;

an alarm operably coupled to said processing unit, said alarm being configured to be activated responsive to said detection signal deviating from a level that corresponds to a predetermined concentration of said same substance; and

an orientation sensor that provides signals to the processing unit in accordance with the orientation of said device, said processor being responsive to said orientation sensor signals to determine said detection signal in accordance with properties of the monitored substance.

21. A monitoring device for monitoring substances, the monitoring device comprising:

at least two sensors configured to detect a same substance and to generate an output signal in response to a detection of the same substance; and

a processing unit operably coupled to the at least two sensors, the processing unit being configured to;

receive each of the output signals from the at least two sensors,

determine a weight of each of the at least two sensors configured to indicate a reliability of each of the at least two sensors, and

determine an aggregate substance concentration reading by aggregating the output signals from the at least two sensors biased toward output signals from sensors indicated as being more reliable based on the weights,

wherein said processing unit determines an aggregate substance concentration according to the relationship;

22. The monitoring device of claim 21, wherein the weight is determined based on at least one of gain, span reserve, historic calibration performance, and historic bump test performance.

23. The monitoring device of claim 21, wherein a gain of a sensor is inversely proportional to a weight of the sensor.

24. The monitoring device of claim 21, wherein a span reserve of a sensor is proportional to a weight of the sensor.

25. The monitoring device of claim 21, further comprising a display operably coupled to the processing unit, the display being configured to show a detection condition for the same substance in accordance with the detection signal.

26. The monitoring device of claim 21, further comprising an alarm operably coupled to the processing unit, the alarm being configured to be activated responsive to the detection signal deviating from a level that corresponds to a predetermined concentration of the same substance.

27. The monitoring device of claim 21, wherein the processing unit is further configured to generate a calibration action responsive to at least two of the output signals deviating by a threshold amount, the calibration action comprising at least one of performing self-calibration and generating a calibration request.

28. The monitoring device of claim 27, wherein the calibration action comprises self-calibration by adjusting a gain of a sensor to minimize variance among the sensors for the substance.

29. The monitoring device of claim 27, wherein the processing unit is further configured to determine a gain of a majority of sensors,

wherein the calibration action comprises self-calibration by adjusting a gain of a deviating sensor to correspond with the gain of the majority of sensors.

30. A monitoring device for monitoring substances, the monitoring device comprising:

at least two sensors configured to detect a same substance and to generate an output signal in response to a detection of the same substance;

an orientation sensor configured to provide an orientation output signal indicating the physical orientation of the monitoring device; and

a processing unit operably coupled to the at least two sensors and the orientation sensor, the processing unit being configured to;

receive each of the output signals from the at least two sensors,

determine a sensor orientation of each of the at least two sensors based on the orientation output,

determine a detection signal for the same substance based on the output signals and the sensor orientation of each of the at least two sensors.

31. The monitoring device of claim 30, wherein the orientation sensor is an accelerometer.

32. The monitoring device of claim 30, wherein determining the detection signal based on the sensor orientation comprises adjusting the detection signal based on at least one of calibration data, field testing data, a distance between at least two sensors, and a location of at least one sensor.