WO2006057550A1 - Sensing module, method for detecting pollutants in air and vehicle ventilation system - Google Patents

Sensing module, method for detecting pollutants in air and vehicle ventilation system Download PDF

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Publication number
WO2006057550A1
WO2006057550A1 PCT/NL2004/000814 NL2004000814W WO2006057550A1 WO 2006057550 A1 WO2006057550 A1 WO 2006057550A1 NL 2004000814 W NL2004000814 W NL 2004000814W WO 2006057550 A1 WO2006057550 A1 WO 2006057550A1
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WO
WIPO (PCT)
Prior art keywords
sensing
sensing layer
processor
response
temperature
Prior art date
Application number
PCT/NL2004/000814
Other languages
French (fr)
Inventor
Tom Urban Artursson
Per Anders Holmberg
Nicolae Barsan
Heiko Eugen Ulmer
Original Assignee
Texas Instruments Holland B.V.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Texas Instruments Holland B.V. filed Critical Texas Instruments Holland B.V.
Priority to PCT/NL2004/000814 priority Critical patent/WO2006057550A1/en
Publication of WO2006057550A1 publication Critical patent/WO2006057550A1/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
    • G01N27/122—Circuits particularly adapted therefor, e.g. linearising circuits
    • G01N27/123—Circuits particularly adapted therefor, e.g. linearising circuits for controlling the temperature
    • G01N27/124—Circuits particularly adapted therefor, e.g. linearising circuits for controlling the temperature varying the temperature, e.g. in a cyclic manner
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
    • B60H1/00—Heating, cooling or ventilating [HVAC] devices
    • B60H1/00642—Control systems or circuits; Control members or indication devices for heating, cooling or ventilating devices
    • B60H1/00735—Control systems or circuits characterised by their input, i.e. by the detection, measurement or calculation of particular conditions, e.g. signal treatment, dynamic models
    • B60H1/008—Control systems or circuits characterised by their input, i.e. by the detection, measurement or calculation of particular conditions, e.g. signal treatment, dynamic models the input being air quality
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
    • B60H3/00—Other air-treating devices
    • B60H3/0085—Smell or pollution preventing arrangements

Definitions

  • the present invention relates to a sensing module for detecting pollutants in air comprising a sensor processor for providing an output signal, the sensor processor being connectable to at least one sensing element, the at least one sensing element comprising a sensing layer of a material, electrodes in contact with the sensing layer to provide electrical characteristics to the sensor processor, and a heating element for heating the sensing layer, in which the sensor processor is connectable to the heating element for controlling the temperature of the sensing layer.
  • Such a sensing module for detecting pollutants is disclosed in European patent EP-B-O 750 191.
  • Two sensor elements are used, one specifically sensitive to oxidizing gasses, and one specifically sensitive for reducing gasses, arranged in a voltage divider arrangement.
  • the output characteristics of the known gas sensor arrangement are dependent on a number of factors, including the operating temperature and the sensor age. Thus, the gas sensor arrangement has to be taken out of its operating environment often and checked for proper functioning and calibration.
  • the present invention seeks to provide a sensing module, e.g. sensitive for air pollutants and for use with a car ventilation control system, which is reliable and allows a long life time without the need for removal of the sensing module for testing and calibration purposes.
  • a sensing module e.g. sensitive for air pollutants and for use with a car ventilation control system
  • a sensing module according to the preamble defined above is provided, in which the sensor processor is arranged to control the heating element to provide a predetermined temperature profile to the sensing layer, and to record the sensing layer response. From the recorded sensing layer response it can be determined whether or not the sensing module is functioning properly. This may be accomplished by looking at different characteristic values of the response curve, such as resistance peak values, time constants of response, etc.
  • the predetermined temperature profile comprises a rising ramp, followed by a falling ramp.
  • the predetermined profile starts at an operating temperature (To), falls to a minimum temperature (Tmin), rises to a maximum temperature (Tmax) above the operating temperature (To), falls to the minimum temperature (Tmin) again, and then rises to the operating temperature (To).
  • This may be accomplished easily, by only setting the operating temperature, minimum temperature and maximum temperature.
  • the form of the temperature profile may alternatively be a triangular shape, or may also have a more complex shape.
  • the present invention can be advantageously used when calibrating the sensing module.
  • the processor may be arranged to provide the predetermined temperature profile in a calibration environment, and to monitor the functionality of the sensing element based on the recorded response of the sensing layer. This allows to determine the proper functioning of the sensing module, and e.g. the current characteristic base value (e.g. resistance RO) of the sensing element.
  • the current characteristic base value e.g. resistance RO
  • the processor is arranged to provide the predetermined temperature profile in a calibration environment, and to determine the sensitivity of the sensing element based on the recorded response of the sensing layer. As the sensitivity of the sensing module may vary over the life time of the sensing module, a re-calibration should be performed on regular intervals.
  • the processor is arranged to provide the predetermined temperature profile in an operational environment, and to determine a degree of pollution of the operational environment by comparing the recorded response of the sensing layer with prerecorded response patterns.
  • the response of the sensing element in an operational environment i.e. with the presence of pollutants such as CO, NO x , etc, depends on the concentration levels of the pollutants.
  • the present invention relates to a vehicle ventilation system, in which supply of outside air to an inner space of the vehicle is controlled using a ventilation controller, the ventilation controller being arranged to interface with a sensing module according to the present invention.
  • the present invention relates to a method for detecting pollutants in air using at least one sensing element, the at least one sensing element comprising a sensing layer of a material, and a heating element for heating the sensing layer, the method comprising controlling the temperature of the sensing layer.
  • the method further comprises controlling the heating element to provide a predetermined temperature profile to the sensing layer, and recording the sensing layer response. Further embodiments of the present method are described in the dependent method claims.
  • the method further comprises an initial calibration of the sensing element in a controlled environment, and compensating for drift of the calibrated sensitivity during operational use as determined from the recorded response of the sensing layer in an operational environment. This allows to use a sensing module for detecting pollutants in air which has a high quality, and maintains its quality over a long span of time.
  • Fig. 1 shows a schematic diagram of an embodiment of a sensing module according to the present invention
  • Fig. 2 shows a cross sectional view of a sensing element as used in the sensing module of Fig. 1;
  • Fig. 3 shows a plot of a temperature profile as applied using the present invention.
  • Fig. 4 shows a number of characteristic response plots of a sensing element as used in the present invention.
  • Electro chemical sensing elements are used presently for detecting pollution in air, such as oxidizable gasses (CO, CH x ,...) and reducable gasses (NO, NO x , etc). These kind of sensing elements may be used to control the ventilation system of a vehicle, such as a passenger car. More general, such sensing elements are used in heating, ventilation and air conditioning systems (HVAC). When pollution occurs in outside air, e.g. when entering a badly ventilated tunnel filled with exhaust fumes, the air vent of the vehicle may be closed off (internal air circulation).
  • HVAC heating, ventilation and air conditioning systems
  • a schematic diagram is shown of a sensing module 1 for use in a vehicle ventilation system.
  • the sensing module 1 comprises one or more sensing elements 3, which are connected to a processor 2.
  • the processor 2 may be a dedicated electronic circuit which processes the signals from the sensing elements 3 (analog or digital circuitry, or a combination of both), or may be in the form of a general purpose processing unit 2 connected to a memory 4 (e.g. an integrated memory).
  • the memory 4 e.g. in the form of semiconductor memory units, may comprise (software) program instructions which control the functioning of the processing unit 2.
  • the processor 2 is arranged to provide an output signal 5, which may be transferred to the vehicle ventilation system (not shown) for controlling the operation thereof.
  • the sensing elements 3 are usually electro chemical sensing elements, which comprise a sensing material of which a physical property, such as its resistance, changes under the influence of the concentration of certain compounds in the ambient air around the sensing element 3.
  • the sensing elements 3 may be especially suited for detecting oxidizable gasses, such as CO and hydrocarbons, reducable gasses, such as NO and NO x , and other compounds, e.g. volatile organic compounds (VOC). Volatile organic compounds may e.g. originate from manure, compost or asphalt. When these compounds or gasses are present in the ambient air of a vehicle, the normal operation of the vehicle's ventilation system would allow these to enter the vehicle interior, which can be unpleasant or even dangerous for the occupants of the vehicle.
  • a cross sectional view is shown of an embodiment of an electrochemical sensor 3 which may be used in the present invention.
  • a thin membrane layer 12 is formed, and the substrate 11 is etched to provide a cavity under the membrane layer 12.
  • a heating element 14 is positioned, on top of which an insulating layer 13 is deposited.
  • electrodes 15 e.g. finger form electrodes
  • a sensitive layer 16 is formed on top of the electrodes 15, e.g. by drop deposition of a material such as polycrystalline SnO 2 .
  • the sensitive layer 16 has an electrical characteristic, e.g. its resistance, which depends on the concentration of certain compounds, such as reducing or oxidizing gasses, in the environment of the sensing element 3. This resistance may be measured using the electrodes 15. As the structure of the actual sensing part of the sensing element 3 is very thin resulting in a low thermal mass, the temperature of the sensing layer 16 is accurately controllable using the heating element 14.
  • Multiple sensing elements 3 may be provided on the same substrate 11 (using multiple cavities), which would e.g. allow to measure the concentration of both reducing and oxidizing gasses. Also, signal processing electronics (such as processor 2 and memory 4) may be integrated in the substrate 11, providing an integrated sensing module 1.
  • the output signal of the sensing element 3 is not only dependent on the concentration of the compounds to be detected, but also dependent on other physical parameters, such as temperature, age of the sensing element 3, etc. Thus, a calibration is required of the sensing element 3, which may be provided by the processor 2 of the sensing module 1.
  • the processor 2 may be programmed to apply a temperature profile, of which an exemplary embodiment is shown in Fig. 3, to the sensing layer 16 using the heating element 14, when the sensing element 3 is in a calibration environment, e.g. comprising clean air.
  • the temperature profile e.g. starts at a first temperature (To), e.g. an operating temperature of 300 0 C, decreases to a minimum temperature (Tmin), e.g. room temperature, and subsequently increases linearly to a maximum temperature (Tmax), e.g. 400 0 C. Then, the temperature again decreases to the minimum temperature Tmax. After that, the temperature increases again to the operating temperature To.
  • the response of the sensing layer 16 is measured, e.g. by measuring the resistance between the electrodes 15, and stored by the processor 2 in memory 4.
  • a number of characteristics related to the sensing element 3 can be deducted. Firstly, it can be established that the sensing element 3 still provides its basic function, i.e. a response is received from the sensing element 3 which is within predetermined boundaries. Furthermore, from the stored response it is possible to determine or estimate the sensitivity of the sensing element 3. E.g., in the stored response, peak values of resistance may be determined with the associated temperature. Also, time constants of response profiles maybe determined.
  • a subset of resistance values as measured during the temperature ramp profile are used, which show a correlation to the sensitivity.
  • other temperature profiles may be used in the present invention, e.g. a triangular profile starting at room temperature, rising to a maximum temperature above the operating temperature, and then decreasing again to room temperature.
  • the parameters determined from the calibration response such as the sensitivity of the sensing element 3, or the entire calibration response, may be stored in the memory 4.
  • the temperature profiling may also be applied to the sensing element 3 during operation.
  • the response of the sensing element 3 to the temperature profile will depend a.o., on the concentration of the pollutant in the environment of the sensing layer 16, for which the sensing element 3 was designed. It is possible to store a number of characteristic response profiles or characteristic parameters of response profiles as a function of e.g. the concentration of pollutants, and to compare or match the actually measured response characteristic with the stored response characteristics to determine or predict the actual pollution concentration.
  • the initial calibration of the sensing element 3 may then be performed in a controlled environment using known gasses, and during operational use, the method of using the temperature profile calibration maybe executed to compensate for drift of the calibrated sensitivity.

Abstract

Sensing module for (and a corresponding method of) detecting pollutants in air comprising a processor (2) connected to a sensing element (3). The sensing element (3) comprises a sensing layer (16), electrodes (15) in contact with the sensing layer (16) to provide electrical characteristics to the processor (2), and a heating element (14) for heating the sensing layer (16). The processor (2) controls the heating element (14) to provide a predetermined temperature profile to the sensing layer (16), and to record the sensing layer response. The sensitivity of the sensing element (3) is determined based on the recorded response of the sensing layer (16). Vehicle ventilation system, in which supply of outside air to an inner space of the vehicle is controlled using a ventillation controller, the ventilation controller being arranged to interface with a sensing module according to the present invention.

Description

SENSING MODULE , METHOD FOR DETECTING POLLUTANTS IN AIR AND VEHICLE
VENTILATION SYSTEM
Field of the invention
The present invention relates to a sensing module for detecting pollutants in air comprising a sensor processor for providing an output signal, the sensor processor being connectable to at least one sensing element, the at least one sensing element comprising a sensing layer of a material, electrodes in contact with the sensing layer to provide electrical characteristics to the sensor processor, and a heating element for heating the sensing layer, in which the sensor processor is connectable to the heating element for controlling the temperature of the sensing layer.
Prior art
Such a sensing module for detecting pollutants is disclosed in European patent EP-B-O 750 191. Two sensor elements are used, one specifically sensitive to oxidizing gasses, and one specifically sensitive for reducing gasses, arranged in a voltage divider arrangement. The output characteristics of the known gas sensor arrangement are dependent on a number of factors, including the operating temperature and the sensor age. Thus, the gas sensor arrangement has to be taken out of its operating environment often and checked for proper functioning and calibration.
Summary of the invention
The present invention seeks to provide a sensing module, e.g. sensitive for air pollutants and for use with a car ventilation control system, which is reliable and allows a long life time without the need for removal of the sensing module for testing and calibration purposes.
According to the present invention, a sensing module according to the preamble defined above is provided, in which the sensor processor is arranged to control the heating element to provide a predetermined temperature profile to the sensing layer, and to record the sensing layer response. From the recorded sensing layer response it can be determined whether or not the sensing module is functioning properly. This may be accomplished by looking at different characteristic values of the response curve, such as resistance peak values, time constants of response, etc. In a first embodiment, the predetermined temperature profile comprises a rising ramp, followed by a falling ramp. When the structure of the sensing element has a sufficiently low heat capacity, it is possible to obtain such a temperature profile using the heating element, e.g. by driving the heating element with a current in accordance with the temperature profile.
In a further embodiment, the predetermined profile starts at an operating temperature (To), falls to a minimum temperature (Tmin), rises to a maximum temperature (Tmax) above the operating temperature (To), falls to the minimum temperature (Tmin) again, and then rises to the operating temperature (To). This may be accomplished easily, by only setting the operating temperature, minimum temperature and maximum temperature. The form of the temperature profile may alternatively be a triangular shape, or may also have a more complex shape.
The present invention can be advantageously used when calibrating the sensing module. The processor may be arranged to provide the predetermined temperature profile in a calibration environment, and to monitor the functionality of the sensing element based on the recorded response of the sensing layer. This allows to determine the proper functioning of the sensing module, and e.g. the current characteristic base value (e.g. resistance RO) of the sensing element.
Alternatively, the processor is arranged to provide the predetermined temperature profile in a calibration environment, and to determine the sensitivity of the sensing element based on the recorded response of the sensing layer. As the sensitivity of the sensing module may vary over the life time of the sensing module, a re-calibration should be performed on regular intervals. hi an even further embodiment of the present invention, the processor is arranged to provide the predetermined temperature profile in an operational environment, and to determine a degree of pollution of the operational environment by comparing the recorded response of the sensing layer with prerecorded response patterns. The response of the sensing element in an operational environment, i.e. with the presence of pollutants such as CO, NOx, etc, depends on the concentration levels of the pollutants. A different pollution level will result in a different (dynamic) response of the sensing element, thus allowing to determine or predict a pollution level by comparing the actual response to the temperature curve with pre-stored responses. In a further aspect, the present invention relates to a vehicle ventilation system, in which supply of outside air to an inner space of the vehicle is controlled using a ventilation controller, the ventilation controller being arranged to interface with a sensing module according to the present invention. In an even further aspect, the present invention relates to a method for detecting pollutants in air using at least one sensing element, the at least one sensing element comprising a sensing layer of a material, and a heating element for heating the sensing layer, the method comprising controlling the temperature of the sensing layer. The method further comprises controlling the heating element to provide a predetermined temperature profile to the sensing layer, and recording the sensing layer response. Further embodiments of the present method are described in the dependent method claims. In a particular embodiment, the method further comprises an initial calibration of the sensing element in a controlled environment, and compensating for drift of the calibrated sensitivity during operational use as determined from the recorded response of the sensing layer in an operational environment. This allows to use a sensing module for detecting pollutants in air which has a high quality, and maintains its quality over a long span of time.
Short description of drawings The present invention will be discussed in more detail below, using a number of exemplary embodiments, with reference to the attached drawings, in which
Fig. 1 shows a schematic diagram of an embodiment of a sensing module according to the present invention;
Fig. 2 shows a cross sectional view of a sensing element as used in the sensing module of Fig. 1;
Fig. 3 shows a plot of a temperature profile as applied using the present invention; and
Fig. 4 shows a number of characteristic response plots of a sensing element as used in the present invention.
Detailed description of exemplary embodiments
Electro chemical sensing elements are used presently for detecting pollution in air, such as oxidizable gasses (CO, CHx,...) and reducable gasses (NO, NOx,...). These kind of sensing elements may be used to control the ventilation system of a vehicle, such as a passenger car. More general, such sensing elements are used in heating, ventilation and air conditioning systems (HVAC). When pollution occurs in outside air, e.g. when entering a badly ventilated tunnel filled with exhaust fumes, the air vent of the vehicle may be closed off (internal air circulation).
In Fig. 1, a schematic diagram is shown of a sensing module 1 for use in a vehicle ventilation system. The sensing module 1 comprises one or more sensing elements 3, which are connected to a processor 2. The processor 2 may be a dedicated electronic circuit which processes the signals from the sensing elements 3 (analog or digital circuitry, or a combination of both), or may be in the form of a general purpose processing unit 2 connected to a memory 4 (e.g. an integrated memory). The memory 4, e.g. in the form of semiconductor memory units, may comprise (software) program instructions which control the functioning of the processing unit 2. The processor 2 is arranged to provide an output signal 5, which may be transferred to the vehicle ventilation system (not shown) for controlling the operation thereof.
The sensing elements 3 are usually electro chemical sensing elements, which comprise a sensing material of which a physical property, such as its resistance, changes under the influence of the concentration of certain compounds in the ambient air around the sensing element 3. The sensing elements 3 may be especially suited for detecting oxidizable gasses, such as CO and hydrocarbons, reducable gasses, such as NO and NOx, and other compounds, e.g. volatile organic compounds (VOC). Volatile organic compounds may e.g. originate from manure, compost or asphalt. When these compounds or gasses are present in the ambient air of a vehicle, the normal operation of the vehicle's ventilation system would allow these to enter the vehicle interior, which can be unpleasant or even dangerous for the occupants of the vehicle. Thus these sensors are normally used to shut of the external air intake when too high a concentration of any of these compounds is detected. hi Fig. 2, a cross sectional view is shown of an embodiment of an electrochemical sensor 3 which may be used in the present invention. On a silicon substrate 11, a thin membrane layer 12 is formed, and the substrate 11 is etched to provide a cavity under the membrane layer 12. On the membrane layer 12, a heating element 14 is positioned, on top of which an insulating layer 13 is deposited. Then, electrodes 15 (e.g. finger form electrodes) are provided on top of the insulating layer 13, above the heating element 14. Finally, a sensitive layer 16 is formed on top of the electrodes 15, e.g. by drop deposition of a material such as polycrystalline SnO2. The sensitive layer 16 has an electrical characteristic, e.g. its resistance, which depends on the concentration of certain compounds, such as reducing or oxidizing gasses, in the environment of the sensing element 3. This resistance may be measured using the electrodes 15. As the structure of the actual sensing part of the sensing element 3 is very thin resulting in a low thermal mass, the temperature of the sensing layer 16 is accurately controllable using the heating element 14.
Multiple sensing elements 3 may be provided on the same substrate 11 (using multiple cavities), which would e.g. allow to measure the concentration of both reducing and oxidizing gasses. Also, signal processing electronics (such as processor 2 and memory 4) may be integrated in the substrate 11, providing an integrated sensing module 1.
Due to the physical nature of the sensing element 3, the output signal of the sensing element 3 is not only dependent on the concentration of the compounds to be detected, but also dependent on other physical parameters, such as temperature, age of the sensing element 3, etc. Thus, a calibration is required of the sensing element 3, which may be provided by the processor 2 of the sensing module 1.
The processor 2 may be programmed to apply a temperature profile, of which an exemplary embodiment is shown in Fig. 3, to the sensing layer 16 using the heating element 14, when the sensing element 3 is in a calibration environment, e.g. comprising clean air. The temperature profile e.g. starts at a first temperature (To), e.g. an operating temperature of 3000C, decreases to a minimum temperature (Tmin), e.g. room temperature, and subsequently increases linearly to a maximum temperature (Tmax), e.g. 4000C. Then, the temperature again decreases to the minimum temperature Tmax. After that, the temperature increases again to the operating temperature To. The response of the sensing layer 16 is measured, e.g. by measuring the resistance between the electrodes 15, and stored by the processor 2 in memory 4.
From the stored response, a number of characteristics related to the sensing element 3 can be deducted. Firstly, it can be established that the sensing element 3 still provides its basic function, i.e. a response is received from the sensing element 3 which is within predetermined boundaries. Furthermore, from the stored response it is possible to determine or estimate the sensitivity of the sensing element 3. E.g., in the stored response, peak values of resistance may be determined with the associated temperature. Also, time constants of response profiles maybe determined.
Alternatively, a subset of resistance values as measured during the temperature ramp profile are used, which show a correlation to the sensitivity. For the skilled person, it will be clear that other temperature profiles may be used in the present invention, e.g. a triangular profile starting at room temperature, rising to a maximum temperature above the operating temperature, and then decreasing again to room temperature.
The parameters determined from the calibration response, such as the sensitivity of the sensing element 3, or the entire calibration response, may be stored in the memory 4.
The temperature profiling may also be applied to the sensing element 3 during operation. The response of the sensing element 3 to the temperature profile will depend a.o., on the concentration of the pollutant in the environment of the sensing layer 16, for which the sensing element 3 was designed. It is possible to store a number of characteristic response profiles or characteristic parameters of response profiles as a function of e.g. the concentration of pollutants, and to compare or match the actually measured response characteristic with the stored response characteristics to determine or predict the actual pollution concentration. The initial calibration of the sensing element 3 may then be performed in a controlled environment using known gasses, and during operational use, the method of using the temperature profile calibration maybe executed to compensate for drift of the calibrated sensitivity.

Claims

1. Sensing module for detecting pollutants in air comprising a processor (2) for providing an output signal, the processor (2) being connectable to at least one sensing element (3), the at least one sensing element (3) comprising a sensing layer (16) of a material, electrodes (15) in contact with the sensing layer to (16) provide electrical characteristics to the processor (2), and a heating element (14) for heating the sensing layer (16), in which the processor (2) is connectable to the heating element (14) for controlling the temperature of the sensing layer (16), characterized in that the processor (2) is arranged to control the heating element (14) to provide a predetermined temperature profile to the sensing layer (16), and to record the sensing layer response.
2. Sensing module according to claim 1 , in which the predetermined temperature profile comprises a rising ramp, followed by a falling ramp.
3. Sensing module according to claim 1 or 2, in which the predetermined profile starts at an operating temperature (To), falls to a minimum temperature (Trnin), rises to a maximum temperature (Tmax) above the operating temperature (To), falls to the minimum temperature (Tmin) again, and then rises to the operating temperature (To).
4. Sensing module according to any one of claims 1-3, in which the processor (2) is arranged to provide the predetermined temperature profile in a calibration environment, and to monitor the functionality of the sensing element (3) based on the recorded response of the sensing layer (16).
5. Sensing module according to any one of claims 1-3, in which the processor (2) is arranged to provide the predetermined temperature profile in a calibration environment, and to determine the sensitivity of the sensing element (3) based on the recorded response of the sensing layer (16).
6. Sensing module according to any one of claims 1-3, in which the processor (2) is arranged to provide the predetermined temperature profile in an operational environment, and to determine a degree of pollution of the operational environment by comparing the recorded response of the sensing layer (16) with prerecorded response patterns.
7. Vehicle ventilation system, in which supply of outside air to an inner space of the vehicle is controlled using a ventilation controller, the ventilation controller being arranged to interface with a sensing module (1) according to any one of claims 1-6.
8. Method for detecting pollutants in air using at least one sensing element (3), the at least one sensing element (3) comprising a sensing layer (16) of a material, and a heating element (14) for heating the sensing layer (16), the method comprising controlling the temperature of the sensing layer (16), characterized in that the method further comprises controlling the heating element (14) to provide a predetermined temperature profile to the sensing layer (16), and recording the sensing layer response.
9. Method according to claim 8, in which the predetermined temperature profile comprises a rising ramp, followed by a falling ramp.
10. Method according to claim 8 or 9, in which the predetermined profile starts at an operating temperature (To), falls to a minimum temperature (Tmin), rises to a maximum temperature (Tmax) above the operating temperature (To), falls to the minimum temperature (Tmin) again, and then rises to the operating temperature (To).
11. Method according to any one of claims 8-10, further comprising providing the predetermined temperature profile in a calibration environment, and monitoring the functionality of the sensing element (3) based on the recorded response of the sensing layer (16).
12. Method according to any one of claims 8-10, further comprising providing the predetermined temperature profile in a calibration environment, and determining the sensitivity of the sensing element (3) based on the recorded response of the sensing layer (16).
13. Method according to any one of claims 8-10, further comprising providing the predetermined temperature profile in an operational environment, and determining a degree of pollution of the operational environment by comparing the recorded response of the sensing layer (16) with prerecorded response patterns.
14. Method according to any one of claims 8-10, further comprising an initial calibration of the sensing element (3) in a controlled environment, and compensating for drift of the calibrated sensitivity during operational use as determined from the recorded response of the sensing layer (16) in an operational environment.
PCT/NL2004/000814 2004-11-25 2004-11-25 Sensing module, method for detecting pollutants in air and vehicle ventilation system WO2006057550A1 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105848939A (en) * 2014-01-10 2016-08-10 奥迪股份公司 Device for diffusing a fragrance, and motor vehicle comprising a device of said type
FR3089010A1 (en) * 2018-11-28 2020-05-29 Rubix S&I Method for detecting at least a quantity of gas of at least one predetermined gas from a sensor for measuring a plurality of gases
EP3917813A4 (en) * 2019-01-29 2022-10-26 Aclima Inc. Sensor and data platforms for vehicle environmental quality management

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4567475A (en) * 1982-04-15 1986-01-28 Cerberus Ag Gas or vapor alarm system including scanning gas sensors
EP0829718A1 (en) * 1996-09-11 1998-03-18 Heinz Prof. Dr. Kohler Apparatus for analysing gases with a semiconducting sensor
EP1109012A2 (en) * 1999-12-09 2001-06-20 Vaisala Oyj Measurement method and system for a humidity of gas concentration sensor
US6276192B1 (en) * 1999-04-14 2001-08-21 Auto Electronic Corporation Gas detecting sensor and device for controlling ventilation systems

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4567475A (en) * 1982-04-15 1986-01-28 Cerberus Ag Gas or vapor alarm system including scanning gas sensors
EP0829718A1 (en) * 1996-09-11 1998-03-18 Heinz Prof. Dr. Kohler Apparatus for analysing gases with a semiconducting sensor
US6276192B1 (en) * 1999-04-14 2001-08-21 Auto Electronic Corporation Gas detecting sensor and device for controlling ventilation systems
EP1109012A2 (en) * 1999-12-09 2001-06-20 Vaisala Oyj Measurement method and system for a humidity of gas concentration sensor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KOHLER H ET AL: "New applications of tin oxide gas sensors - I. Molecular identification by cyclic variation of the working temperature and numerical analysis of the signals", SENSORS AND ACTUATORS B, ELSEVIER SEQUOIA S.A., LAUSANNE, CH, vol. 61, no. 1-3, 14 December 1999 (1999-12-14), pages 163 - 169, XP004185148, ISSN: 0925-4005 *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105848939A (en) * 2014-01-10 2016-08-10 奥迪股份公司 Device for diffusing a fragrance, and motor vehicle comprising a device of said type
CN105848939B (en) * 2014-01-10 2018-04-10 奥迪股份公司 For distributing the device of aromatic substance and there is the motor vehicle of this device
US10179184B2 (en) 2014-01-10 2019-01-15 Audi Ag Device for dispensing a fragrance, and motor vehicle having such a device
FR3089010A1 (en) * 2018-11-28 2020-05-29 Rubix S&I Method for detecting at least a quantity of gas of at least one predetermined gas from a sensor for measuring a plurality of gases
WO2020109160A1 (en) 2018-11-28 2020-06-04 Rubix S&I Method for detecting at least one gas quantity of at least one predetermined gas by a measurement sensor of a plurality of gases
EP3917813A4 (en) * 2019-01-29 2022-10-26 Aclima Inc. Sensor and data platforms for vehicle environmental quality management
US11833882B2 (en) 2019-01-29 2023-12-05 Aclima Inc. Sensor and data platforms for vehicle environmental quality management

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