Chemical vapor sensor having an active and a passive measurement mode

• US 20060153740A1
• Filed: 01/12/2005
• Published: 07/13/2006
• Est. Priority Date: 01/12/2005
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG (Aptiv PLC)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Sultan, Michel F., Lambert, David K.
• Granted Patent: US 7,279,132 B2
• Time in Patent Office: Days
• US Class Current: 422/88
• CPC Class Codes: B60K 28/06 responsive to incapacity of driver
• CPC Class Codes: B60K 28/063 preventing starting of vehicles
• CPC Class Codes: B60W 2540/24 Drug level, e.g. alcohol
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 21/61 Non-dispersive gas analysers G01N21/3504 takes precedence
• CPC Class Codes: G01N 33/4972 Determining alcohol content for vehicle safety devices B60K28/06
• CPC Class Codes: Y10T 436/11 Automated chemical analysis
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction
• CPC Class Codes: Y10T 436/25875 Gaseous sample or with change of physical state

Abstract

A chemical vapor sensor is provided that measures a chemical species of interest with high sensitivity and chemical specificity. In an aspect, an ethanol vapor sensor is provided, sized for being inconspicuous and on-board a vehicle, having a passive measurement mode and an active breathalyzer mode, for detecting a motor vehicle driver that exceeds a legal limit of blood alcohol concentration (BAC), for use with vehicle safety systems. For the passive mode, a vapor concentrator is utilized to amplify a sampled vapor concentration to a detectible level for use with an infrared (IR) detector. In an aspect, ethanol vapor in a vehicle cabin is passively measured and if a predetermined ethanol level is measured, a countermeasure is invoked to improve safety. In an aspect, an active breathalyzer is used as a countermeasure. The active breathalyzer can be imposed for a number of vehicle trips or for a predetermined time period.

Claims

1. A chemical vapor sensor comprising:

an infrared source for generating infrared waves;

an infrared detector for measuring the intensity of the infrared waves generated from the infrared source;

a vapor concentrator including a vapor adsorber and a heating source to heat the vapor adsorber, for concentrating vapor from a sample volume of air, wherein the concentrated vapor is passed into a path of the infrared waves;

a first sampling intake portion for passively acquiring the sample volume of air and passing the sample volume of air to the vapor concentrator; and

a second sampling intake portion for actively acquiring a sample volume of unmixed gas and passing the sample volume of unmixed gas into a path of the infrared waves.

2. The chemical vapor sensor as in claim 1, further comprising:

an infrared filter for selecting a range of infrared frequency or wavelength that is adsorbed by one of the sample volume of air and the sample volume of unmixed gas; and

an infrared absorption cell defining an inlet for taking in the sample volume of air and the sample volume of unmixed gas, and an outlet for expelling the sample volume of air and the sample volume of unmixed gas.

3. The chemical vapor sensor as in claim 1, further comprising:

a first flow valve positioned to open when the first sampling intake portion is employed;

a second flow valve positioned to open when the second sampling intake portion is employed, wherein the first flow valve and the second flow valve open at different times; and

an air flow source for forcing the sample volume of air from the first sampling intake portion, through the vapor adsorber and through the infrared absorption cell.

4. The chemical vapor sensor as in claim 1, wherein the unmixed gas is human breath, the sample volume of air is sampled from a motor vehicle cabin without requiring active involvement of a vehicle driver, and the infrared detector measures ethanol vapor.

5. The chemical vapor sensor as in claim 4, wherein the infrared detector can measure ethanol concentration in the sample volume of air of at least 0.1 parts per million (ppm), and can measure ethanol concentration in the human breath of at least 150 ppm.

6. The chemical vapor sensor as in claim 4, further comprising a device for instructing a safety response if at least one of ethanol concentration exceeds a predetermined limit in the vehicle cabin and ethanol concentration exceeds a predetermined limit in the human breath, wherein the safety response includes at least one of setting an ethanol flag, setting an ethanol flag counter which requires an active ethanol breathalyzer test for at least one of a predetermined number of vehicle trips and a predetermined time to prevent the vehicle engine from restarting until a driver'"'"'s BAC is measured as a level established as legal to operate a motor vehicle, warning passengers to fasten seat belts, increasing a minimum headway distance behind a preceding vehicle, constraining vehicle performance, and transmitting vehicle cabin ethanol measurements to police and to a vehicle recorder.

7. An ethanol vapor sensor having an active and passive mode for safe vehicle operation comprising:

an infrared source for generating infrared waves;

an infrared detector for measuring the intensity of the infrared waves generated from the infrared source;

a vapor concentrator including a vapor adsorber and a heating source to heat the vapor adsorber, for concentrating vapor from a sample volume of air from a motor vehicle cabin, wherein the concentrated vapor is passed into a path of the infrared waves;

a first sampling intake portion for passively acquiring the sample volume of air and passing the sample volume of air to the vapor concentrator, wherein the first sampling intake portion is situated in one of the vehicle cabin ceiling, dashboard, steering column, steering wheel, and air intake vent;

a second sampling intake portion for actively acquiring a sample volume of human breath and passing the sample volume of human breath into a path of the infrared waves;

an infrared filter for selecting a range of infrared frequency or wavelength that is adsorbed by one of the sample volume of air and the sample volume of human breath; and

an infrared absorption cell defining an inlet for taking in the sample volume of air and the sample volume of human breath, and an outlet for expelling the sample volume of air and the sample volume of human breath.

8. The ethanol vapor sensor as in claim 7, further comprising:

a first flow valve positioned to open when the first sampling intake portion is employed;

a second flow valve positioned to open when the second sampling intake portion is employed, wherein the first flow valve and the second flow valve open at different times; and

an air flow source for forcing the sample volume of air from the first sampling intake portion, through the vapor adsorber and through the infrared absorption cell.

9. The ethanol vapor sensor as in claim 7, wherein the infrared detector can measure ethanol concentration in the sample volume of air of at least 0.1 parts per million (ppm), and can measure ethanol concentration in the human breath of at least 150 ppm.

10. The ethanol vapor sensor as in claim 7, further comprising a device for instructing a safety response if at least one of ethanol concentration exceeds a predetermined limit in the vehicle cabin and ethanol concentration exceeds a predetermined limit in the human breath, wherein the safety response includes at least one of setting an ethanol flag, setting an ethanol flag counter which requires an active ethanol breathalyzer test for at least one of a predetermined number of vehicle trips and a predetermined time to prevent the vehicle engine from restarting until a driver'"'"'s BAC is measured as a level established as legal to operate a motor vehicle, warning passengers to fasten seat belts, increasing a minimum headway distance behind a preceding vehicle, constraining vehicle performance, and transmitting vehicle cabin ethanol measurements to police and to a vehicle recorder.

11. The ethanol vapor sensor as in claim 7, wherein the infrared detector utilizes a single absorption channel for infrared detection.

12. A method of measuring a chemical vapor concentration comprising:

utilizing a chemical vapor passive sensor when one of;

a flag setting is set to a first setting, and a chemical vapor active sensor detects that a first chemical vapor concentration is below a first predetermined concentration;

utilizing the chemical vapor active sensor when the flag is set to a second setting;

setting the flag to the first setting when the chemical vapor passive sensor is utilized and detects that a second chemical vapor concentration is within a second predetermined concentration range; and

setting the flag to the second setting when the chemical vapor passive sensor is utilized and detects that the second chemical vapor concentration exceeds the second predetermined concentration range.

13. The method of measuring a chemical vapor concentration as in claim 12, wherein utilizing the chemical vapor passive sensor comprises:

passing air, including sample vapor, through an adsorber;

measuring an output (designated V_off) of an infrared detector, with an infrared source deactivated;

heating the adsorber;

measuring an output (designated V_on) of the infrared detector, with the infrared source activated;

passing concentrated sample vapor from the adsorber into and through the infrared absorption cell at a predetermined time;

measuring a change in an output (designated V_sig) of the infrared detector; and

calculating the ratio V_sig/(V_on−

V_off).

14. The method of measuring a chemical vapor concentration as in claim 13, wherein passing concentrated sample vapor from the adsorber into and through the infrared absorption cell comprises:

activating air flow just long enough to transfer concentrated sample vapor from the adsorber into the infrared absorption cell;

holding the concentrated sample vapor in the infrared absorption cell for a predetermined and desired time; and

activating air flow again to purge the adsorber and the infrared absorption cell of any concentrated sample vapor.

15. The method of measuring a chemical vapor concentration as in claim 13, wherein passing air, including sample vapor, through an adsorber comprises passing vehicle cabin air through an adsorber, and wherein the sample vapor is ethanol vapor.

16. The method of measuring a chemical vapor concentration as in claim 15, further comprising imposing a safety response when the passive sensor detects that the sample vehicle cabin ethanol vapor indicates that a vehicle occupant exceeds the legal BAC for a driver, wherein the safety response includes at least one of setting the flag to the second setting, setting a flag counter which requires an active breathalyzer test, utilizing the active sensor, for at least one of a predetermined number of vehicle trips and predetermined time to prevent the vehicle engine from restarting until a driver'"'"'s BAC is measured as a level established as legal to operate a motor vehicle, warning passengers to fasten seat belts, increasing a minimum headway distance behind a preceding vehicle, constraining vehicle performance, transmitting vehicle cabin ethanol measurements to police and to a vehicle recorder.

17. The method of measuring a chemical vapor concentration as in claim 16, wherein a microcontroller calculates the ratio V_sig/(V_on−

V_off), and instructs and carries out the safety response.

18. The method of measuring a chemical vapor concentration as in claim 12, wherein utilizing the chemical vapor active sensor comprises:

passing unmixed gas into an infrared absorption cell; and

measuring the unmixed gas infrared absorption within the infrared absorption cell with an infrared source on, utilizing an infrared detector.

19. The method of measuring a chemical vapor concentration as in claim 18, wherein passing unmixed gas comprises passing human breath, wherein measuring the unmixed gas infrared absorption comprises measuring ethanol infrared absorption, and wherein the first predetermined concentration is less than 210 parts per million (ppm).

20. The method of measuring a chemical vapor concentration as in claim 19, further comprising imposing a safety response when the active sensor detects that the sample human breath ethanol vapor exceeds the first predetermined concentration, wherein the safety response includes at least one of setting a flag counter which requires an active breathalyzer test (utilizing the active sensor) for at least one of a predetermined number of vehicle trips and predetermined time to prevent the vehicle engine from restarting until a driver'"'"'s BAC is measured as a level established as legal to operate a motor vehicle.

21. The method of measuring a chemical vapor concentration as in claim 12, wherein the first setting is a pass setting, and the second setting is a fail setting.

22. The method of measuring a chemical vapor concentration as in claim 12, further comprising at least one of utilizing the chemical vapor active sensor when the flag is set to first, and utilizing the chemical vapor passive sensor when the flag is set to second.

23. A method to avert an unlawfully intoxicated driver from operating a vehicle comprising:

utilizing a passive ethanol vapor sensor to measure ethanol vapor concentration in air from a vehicle cabin; and

imposing a safety response when the passive ethanol vapor sensor detects that a sample of vehicle cabin air indicates that a vehicle occupant exceeds the legal blood alcohol concentration (BAC) for a driver, wherein the safety response includes at least one of setting a counter which requires an active breathalyzer test, which utilizes an active ethanol vapor sensor, for at least one of a predetermined number of vehicle trips and predetermined time to prevent the vehicle engine from restarting until a driver'"'"'s BAC is measured as a level established as legal to operate a motor vehicle, warning passengers to fasten seat belts, and transmitting vehicle cabin ethanol measurements to a vehicle recorder.

24. The method as in claim 23, wherein utilizing a passive ethanol vapor sensor comprises:

passing vehicle cabin air, including sample ethanol vapor, through an adsorber;

measuring an output (designated V_off) of an infrared detector, with an infrared source deactivated;

heating the adsorber;

measuring an output (designated V_on) of the infrared detector, with the infrared source activated;

passing concentrated sample ethanol vapor from the adsorber into and through an infrared absorption cell at a predetermined time;

measuring a change in an output (designated V_sig) of the infrared detector; and

calculating the ratio V_sig/(V_on−

V_off).

25. The method as in claim 24, wherein the infrared detector measures ethanol concentration in the vehicle cabin air of at least 0.1 parts per million (ppm).

26. The method as in claim 25, wherein the infrared detector measures ethanol concentration in the vehicle cabin air of 0.1 ppm to 10 ppm, including a standard deviation.

27. The method as in claim 23, wherein utilizing an active ethanol vapor sensor comprises:

passing unmixed human breath into an infrared absorption cell; and

measuring the unmixed human breath ethanol infrared absorption within the infrared absorption cell with an infrared source on, utilizing an infrared detector.