Dynamic calorimetric sensor system

• US 5,996,337 A
• Filed: 05/11/1998
• Issued: 12/07/1999
• Est. Priority Date: 02/06/1998
• Status: Expired due to Term

• Current Assignee: Engelhard Corporation (BASF SE), Continental Automotive Systems, Inc. (Continental AG)
• Original Assignee: Engelhard Corporation (BASF SE), Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Koermer, Gerald Stephen, Naber, Jeffrey Donald, Blosser, Patrick Wayne
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Tran, Binh
• Application Number:
  US09/075,798
• Time in Patent Office: 575 Days
• Field of Search: 60/274, 60/276, 60/277, 60/285, 60/286, 60/278, 60/284, 60/300, 701/103, 701/108, 701/109
• US Class Current: 60/274
• CPC Class Codes: F01N 11/00 Monitoring or diagnostic devices for exhaust-gas treatment apparatus , e.g. for catalytic activity safety, indicating or supervising devices for internal combustion engines F02B77/08; testing of machines G01M13/00
• CPC Class Codes: F01N 11/007 the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus
• CPC Class Codes: F01N 13/009 having two or more separate purifying devices arranged in series
• CPC Class Codes: F01N 2550/02 Catalytic activity of catalytic converters
• CPC Class Codes: F02D 2041/1432 the system including a filter, e.g. a low pass or high pass filter
• CPC Class Codes: F02D 2041/288 for performing a transformation into the frequency domain, e.g. Fourier transformation
• CPC Class Codes: F02D 41/0055 Special engine operating conditions, e.g. for regeneration of exhaust gas treatment apparatus
• CPC Class Codes: F02D 41/1408 Dithering techniques
• CPC Class Codes: F02D 41/1444 characterised by the characteristics of the combustion gases
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A calorimetric sensor system requires a vehicle'"'"'s internal combustion engine to cyclically operate between first and second conditions to repeatedly produce a varying exhaust gas composition which is consistent from cycle to cycle. The rate of change of the calorimetric sensor'"'"'s signal as the engine cycles from one to the other condition is mathematically factored, after signal filtering at frequencies of the induced perturbation, to provide signals indicative of the emissions concentration in the exhaust gases, the air/fuel ratio of the engine and whether the engine is operating lean or rich. The signals can be used as fuel control engine signals as well as OBD signals. Additionally, the system can control industrial processes through small process perturbations affecting the compositions of process gases.

Claims

1. An on-board monitoring and/or control system for use and in combination with a vehicle having an internal combustion engine emitting, during operation, exhaust gases, said system comprising:

a) control means causing said engine to cycle between first and second extreme operating conditions to produce an exhaust gas having generally, consistently varying concentrations of specific emissions during each cycle which are repeatedly reproduced from cycle to cycle;

b) sensor means for producing a continuous calorimetric signal indicative of the changes in the exhaust gas composition during each cycle;

c) means to generate a function signal by analyzing the changes in said calorimetric signal; and

d) means to apply said function signal to a control on said vehicle for monitoring and/or controlling a function of said vehicle.

2. The system of claim 1 wherein said sensor means includes a sensor having a reactor area at temperatures higher than the exhaust gas temperature continuously receiving a slip stream of said exhaust gases, said reactor area having an active surface tending to promote processes wherein energy is liberated or consumed with said exhaust gases in contact therewith and measured by said sensing means to produce said calorimetric signal.

3. The system of claim 2 wherein said control means is effective to cycle said engine at frequencies such that said energy reactions at said reactor area do not reach steady state at said first and second operating condition.

4. The system of claim 1 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

5. The system of claim 4 wherein said modulation causes a sine wave calorimetric signal.

6. The system of claim 3 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

7. The system of claim 6 wherein said modulation causes a sine wave calorimetric signal.

8. The system of claim 2 wherein said reaction area has a material coating promoting reactions of said exhaust gas that liberate or consume energy.

9. The system of claim 8 wherein said material coating is one or more coatings promoting exothermic or endothermic reactions selected from the group consisting of i) base-metal compounds with various base metal oxidation states, ii) precious metals, iii) precious metal compounds with various precious metal oxidation states, iv) catalysts of the type having at least one precious metal coated or impregnated on a washcoat of alumina or ceria zirconia applied to said reaction area and v) combinations thereof.

10. The system of claim 8 wherein said coating is one or more adsorbent coatings selected from the group consisting of i) zeolites, ii) polymers, iii) super-absorptive polymers, iv) desiccants and materials that adsorb HFC'"'"'s.

11. The system of claim 1 wherein said control means includes means to vary one or more operating conditions of said engine selected from the group consisting of i) valve timing, ii) spark timing, iii) speed, iv) exhaust gas recirculation, v) injection timing, vi) air to fuel ratio, vii) mass air flow viii) manifold air pressure and ix) perturbation frequency.

12. The system of claim 1 wherein said vehicular function signal is one or more signals selected from the group consisting of a) control feedback signal utilized by ECM means for controlling set ratios of air to fuel metered to the combustion chambers of said engine, or EGR gases or spark, valve or injection timing or mass air flow or pressure or perturbation frequency symmetry or wave form, b) a trim signal for calibrating control devices on said vehicle, c) an emissions monitoring signal indicative of the concentration of one or more specific gases emissions, d) a catalytic converter efficiency signal for monitoring the efficiency of the catalytic converter, e) an OBD signal indicative of a failure of a pollution control system on the vehicle and f) an emissions compliant storage signal for determining if said vehicle is in compliance with emission requirements specified during specific drive cycles.

13. The system of claim 1 wherein said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

14. The system of claim 13 wherein said periodic means includes means to digitize said calorimetric signal into data signals, means to transform said data into a frequency domain having a spectrum of wave frequency components and said interpolating means selecting at least one frequency component from said spectrum at multiples of the cycle frequency for evaluation.

15. The system of claim 2 wherein said control means includes means to vary one or more operating conditions of said engine selected from the group consisting of i) valve timing, ii) spark timing, iii) speed, iv) exhaust gas recirculation, v) injection timing, vi) air to fuel ratio, vii) mass air flow viii) manifold air pressure and ix) perturbation frequency.

16. The system of claim 2 wherein said vehicular function signal is one or more signals selected from the group consisting of a) control feedback signal utilized by ECM means for controlling set ratios of air to fuel metered to the combustion chambers of said engine, or EGR gases or spark, valve or injection timing or mass air flow or pressure or perturbation frequency symmetry or wave form, b) a trim signal for calibrating control devices on said vehicle, c) an emissions monitoring signal indicative of the concentration of one or more specific gases emissions, d) a catalytic converter efficiency signal for monitoring the efficiency of the catalytic converter, e) an OBD signal indicative of a failure of a pollution control system on the vehicle and f) an emissions compliant storage signal for determining if said vehicle is in compliance with emission requirements specified during specific drive cycles.

17. The system of claim 2 wherein said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

18. The system of claim 2 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

19. The system of claim 11 wherein said vehicular function signal is one or more signals selected from the group consisting of a) control feedback signal utilized by ECM means for controlling set ratios of air to fuel metered to the combustion chambers of said engine, or EGR gases or spark, valve or injection timing or mass air flow or pressure or perturbation frequency symmetry or wave form, b) a trim signal for calibrating control devices on said vehicle, c) an emissions monitoring signal indicative of the concentration of one or more specific gases emissions, d) a catalytic converter efficiency signal for monitoring the efficiency of the catalytic converter, e) an OBD signal indicative of a failure of a pollution control system on the vehicle and f) an emissions compliant storage signal for determining if said vehicle is in compliance with emission requirements specified during specific drive cycles.

20. The system of claim 11 wherein said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

21. The system of claim 11 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

22. The system of claim 12 wherein said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

23. The system of claim 12 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

24. The system of claim 13 wherein said control means causes said cycle to modulate the composition of said exhaust gases during each cycle such that said calorimetric signal takes a wave form selected from the group consisting of i) sine waves, ii) triangular waves, iii) saw tooth waves, iv) square waves, v) asymmetric waves, and vi) combinations thereof.

25. The system of claim 2 further including

a light-off catalytic converter spaced closely adjacent said engine substantially lacking chemical compositions capable of storing oxygen;

an underfloor catalytic converter downstream of said light-off catalytic converter;

said sensor being positioned downstream of said light-off converter and upstream of said underfloor catalytic converter;

injection means for metering fixed quantities of fuel into the combustion chambers of said engine; and

wherein said means to generate producing a first signal indicative of the concentration of at least one specific gaseous emission in said exhaust gas and a second feedback signal indicative of the quantities of air and fuel supplied to the combustion chambers of said engine;

said means to apply further including ECM means for generating an injection signal correlated to said first and second signals to produce an exhaust gas having specific gaseous emission concentrations capable of being converted by said light-off catalyst whereby the life of said underfloor catalytic converter is extended by said ECM means changing said injection signal to maintain emission concentrations in said exhaust gas at levels capable of being converted by said light-off catalyst as said light-off catalyst ages.

26. The system of claim 25 wherein said underfloor catalytic converter has a washcoat intentionally lacking ceria composition.

27. The system of claim 25 wherein said injection signal corresponds to the frequency at which said control means cycles said operating conditions, said ECM means changing said frequency as said light-off catalytic converter ages to cause said engine to produce lesser concentrations of said specific gaseous emission sensed by said sensor.

28. The system of claim 25 wherein said injection means further includes pulse width modulating means for controlling the quantities and duration of fuel supplied to said combustion chambers of said engine pursuant to said injection signal, said injection signal corresponding to an air to fuel ratio at which said fixed quantities of fuel are metered to said combustion chambers by said pulse width modulating means, said ECM means causing said injection means to change said fixed quantities of fuel as said light-off catalytic converter ages in response to said first signal to cause said engine to produce lesser concentrations of said specific gaseous emission sensed by said sensor.

29. The system of claim 25 wherein said means to generate includes said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

30. The system of claim 29 wherein said periodic means includes means to digitize said calorimetric signal into data signals, means to transform said data into a frequency domain having a spectrum of wave frequency components and said interpolating means selecting at least one frequency component from said spectrum at multiples of the cycle frequency for evaluation.

31. The system of claim 29 wherein said feedback signal is said wave phase signal correlated to said frequency at which said control means cycles said operating condition.

32. The system of claim 30 wherein said interpolating means compares first and second wave frequency components of said calorimetric signal at different frequency multiples of said cycle for determining the lambda bias at which said engine operates.

33. The system of claim 25 wherein said injection means further includes exhaust gas recirculation means for metering a set portion of exhaust gas with said combustion air and said fuel into said combustion chambers of said engine pursuant to said injection signal, said ECM means producing injection signals changing the quantities of exhaust gas metered into said combustion chambers to cause said engine to produce lesser concentrations of said specific gaseous emission sensed by said senor.

34. The system of claim 25 wherein said light-off catalytic converter has a washcoat substantially lacking ceria and capable of converting HC and H₂ emissions in said exhaust gas to harmless emissions, said specific gaseous emissions sensed by said sensor being HC, NO, CO and H₂.

35. The system of claim 34 wherein said sensor has a second reactor area, said first reactor area having a catalyst coating promoting processes wherein energy is liberated or consumed with all combustibles in said exhaust gases and said second reactor having a second catalyst coating promoting selective processes with CO and H₂ wherein energy is liberated or consumed whereby said sensor signal is indicative of the HC concentration present in said exhaust gases.

36. The system of claim 35 wherein said injection means further including means to supply a set quantity of recirculated exhaust gases with said air to avoid significant concentrations of NO_x in said exhaust gas.

37. The system of claim 34 wherein said washcoat of said light-off catalyst is substantially impregnated with Palladium only for converting regulated emissions.

38. The system of claim 2 wherein said control means cycles said operating conditions at a frequency not less than about 1 Hz and said means to generate further includes bandwidth filter means for filtering said calorimetric signal at frequencies equal to or multiples of the frequency of said cycle whereby said calorimetric signal is rapidly produced at filtered frequencies to reduce noise.

39. The system of claim 2 further including a light-off catalytic converter positioned close to said engine for converting hydrocarbon emissions produced by said engine to harmless emissions, said sensor positioned downstream of said light-off catalytic converter and wherein said operating condition is a set quantity of air to fuel mixture injected into the combustion chambers of said engine correlated to lambda where a lambda value of 1 means that precise amount of combustion air metered with a precise amount of fuel to sustain stoichiometric combustion, said control means operable to cycle at a set frequency an air to fuel mixture between first and second lambda values set at the limit of the cycle, said means to generate operable to determine the change in amplitude in said calorimetric signal between the cycle limits, said change in amplitude being said function signal and said means to apply comparing said function signal to a stored calibrated value indicative of the operation of an acceptable catalytic converter and actuating a warning mechanism if said stored value is exceeded.

40. The system of claim 39 wherein said first lambda value is set to produces a lean engine condition and said second lambda produces a more lean engine condition, said control means cycling said engine from a lean condition to a more lean condition.

41. The system of claim 39 wherein said lambda values are set close to stoichiometric.

42. The system of claim 39 wherein one of said lambda values is set less than 1 to produce a rich exhaust gas mixture and the other lambda value is set greater than 1 to produce a lean exhaust gas mixture.

43. The system of claim 39 wherein said means to generate includes bandpass filter means for filtering calorimetric signals at a frequency equal to or at integer multiples of said set frequency.

44. The system of claim 39 wherein lambda modulated in sine wave form between its first and second limits.

45. The system of claim 39 said means to apply further includes storage means for recording said function signals at various operating conditions of said vehicle specified in a drive cycle and means for comparing recorded signals to specified emission levels for specified vehicle operating conditions to determine if said vehicle is in compliance with drive cycle emission standards.

46. The system of claim 45 wherein said storage means further includes means to record engine speed and means to record engine torque, said storage means recording engine speed and engine torque at the time a function signal was generated whereby any regulated drive cycle can be replicated.

47. The system of claim 39 wherein said stored value is a value indicative of the efficiency of said catalytic converter.

48. The system of claim 2 wherein said control means includes injection means for injecting set quantities of fuel into the combustion chambers of said engine and said means to apply including ECM means causing said set quantities of fuel injected by said injection means and combustion air to said combustion chambers to cyclically vary between a first set ratio of combustion air to fuel and a second set ratio of combustion air to fuel, to produce said varying concentrations of emissions during said cycle, said function signal utilized by said ECM means to verify and adjust said first and second ratios.

49. The system of claim 48 wherein said means to generate includes, at least during sensing, periodic means for producing a calorimetric signal having a periodic wave form at frequencies correlated to that at which said engine is cycled and interpolating means for mathematically analyzing one or more wave characteristics of said periodic calorimetric signal selected from the group consisting of i) wave amplitude, ii) wave phase and iii) wave frequency component relationship to induced perturbations caused by said control means.

50. The system of claim 49 wherein said periodic means includes means to digitize said calorimetric signal into data signals, means to transform said data into a frequency domain having a spectrum of wave frequency components and said interpolating means selecting at least one frequency component from said spectrum at multiples of the cycle frequency for evaluation.

51. The system of claim 50 wherein said interpolating means compares first and second wave frequency components of said calorimetric signal at different frequency multiples of said cycle for determining the lambda bias at which said engine operates.

52. The system of claim 48 wherein said injection means includes a fuel injector for each combustion chamber of said engine, each fuel injector having pulse width modulating means for controlling the quantities and timing of fuel supplied each combustion chamber by said fuel injector in accordance with an injection signal, said ECM means supplying said injection signal to each fuel injector and further including calibration means for variably changing one of said ratios for one of said fuel injectors while said first and second ratios for the other combustion chambers remain unchanged and correlating said function signals generated to a programmed air to fuel ratio to produce said injection signal whereby each injector has a calibrated injection signal which is adjusted and/or functionally verified during vehicle operation.

53. The system of claim 48 further including EGR means causing a set portion of said exhaust gas to be recirculated back to said engine for mixing with said combustion air, said ECM means generating an EGR signal to cause said set portion of said exhaust gas to cyclically vary thereby varying said set ratios of combustion air to fuel, said function signal utilized by said ECM means to adjust said EGR signal and verify the operation of said EGR means.

54. The system of claim 53 further including

a light-off catalytic converter spaced closely adjacent said engine substantially lacking chemical compositions capable of storing oxygen;

an underfloor catalytic converter downstream of said light-off catalytic converter;

said sensor being positioned downstream of said light-off converter and upstream of said underfloor catalytic converter;

said sensor having a selective catalyst applied to said reactor area to promote heat reactions of selective gaseous emissions within said gas compositions;

said means to generate additionally generating a function signal from the amplitude of said calorimetric signal which is indicative of the concentration of said selective gaseous emissions present in said exhaust gas composition;

a warning means actuated by said means to apply when said means to apply determines from said function signal that said engine produces said selective emissions at concentrations beyond that specified by a regulatory standard.

55. The system of claim 54 wherein said means to generate a function signal produces an emission concentration signal, an air to fuel ratio signal and an EGR signal, said means to apply said function signal when actuating said warning means further including means to vary the air to fuel ratio supplied by said injection means to determine if said sensor detects a similarly varying fuel ratio signal, and means to vary said EGR means to determine if said sensor detects a corresponding varying EGR signal whereby the failure of said vehicle to meet emission standards is attributed to one or more of said injection means, said EGR means and said light-off catalytic converter.

56. The system of claim 2 wherein said reactor area is coated with a catalyst promoting reactions of HC and CO emissions within said exhaust gases, said sensor having heater means for maintaining said reactor area at a minimum elevated temperature, said first condition is a lean engine condition and said second condition is a more lean engine condition, said control means cycling between said first and second conditions at a set frequency, said means to generate a function signal determining the change in the amplitude of said calorimetric signal for each cycle, said change in amplitude indicative of HC and CO concentrations within said exhaust gases and warning means actuated by said applying means when said function signal exceeds a stored value whereby said system is able to detect HC and CO emissions produced in diesel and GDI engines having low temperature exhaust gases or engine operated at excess lean conditions.

57. The system of claim 56 wherein said control means is further effective to adjust said operating conditions of said engine to raise the temperature of said exhaust gases should said function signal be less than a set value.

58. The system of claim 2 wherein said system includes a light-off catalytic converter spaced closely adjacent said engine substantially lacking chemical compositions capable of storing oxygen;

said sensor downstream of said light-off catalytic converter and including heater means for heating said reactor area to a first elevated temperature upon cold start of said engine;

said operating condition being a combustion air to fuel ratio cycled between first and second values at a set frequency;

said means to generate said function signal determining the phase of said calorimetric signal relative to the frequency at which said air to fuel ratio is cycled and said means to apply effective to control said air to fuel ratio supplied to the combustion engine of said vehicle during cold start to minimize said engine producing exhaust gases having objectionable emissions.

59. The system of claim 2 further including an EGO sensor downstream of said engine for sensing the presence of oxygen in said exhaust gas and regulating the ratio of combustion air to fuel supplied to the combustion chambers of said engine, said ratio of combustion air to fuel necessary to sustain stoichiometric combustion defined as a lambda value of 1, said first operating condition being an air to fuel ratio greater than a lambda value of 1 by a set amount, said second operating condition being an air to fuel ratio lesser than a lambda value of 1 by said set amount, said control means cycling said first and second operating conditions at a set frequency, said means to generate determining the relationship of selected frequency compensate of said calorimetric signal relative to the cycle frequency to develop a function signal indicative of lambda bias, said means to apply including means to adjust said EGO sensor for drift by said function signal.

84. The system of claim 25 wherein said ECM means is effective to change the frequency of said cycle as said catalytic converter ages.

85. The system of claim 25 wherein said ECM means is effective to change the limits of said operating conditions as said catalytic converter ages.

86. The system of claim 48 wherein said injection means includes a plurality of fuel injectors for a like plurality of combustion chambers, each fuel injector having pulse width modulating means controlling the timing and amount of fuel supplied each combustion chamber by each combustion chamber'"'"'s respective fuel injector in accordance with an injection signal, said ECM means supplying injection signals to said fuel injectors such that a first plurality of said fuel injections produce an air-to-fuel ratio at a first lambda bias and a second equal plurality of said fuel injectors produce an air-to-fuel ratio at a second lambda bias, said air-to-fuel ratios bring said operating conditions and varied by said pulse width modulating means.

87. The system of claim 86 wherein said lambda perturbation amplitude controlled by said first and second pluralities of said fuel injectors remains constant.

88. The system of claim 87 wherein said means to generate a function signal includes means to sense the speed of said engine.

89. The system of claim 50 wherein said ECM means causes said first and second set ratios to sequentially vary at fixed increments in a lambda sweep over a fixed time period encompassing a fixed number of cycles while the difference between said first and second ratios remains generally constant;

and said interpolating means detecting the maximum amplitude of the second order frequency component of said spectrum and selecting the first and second air-to-fuel ratios whereat said maximum amplitude occurred in said sweep, said selected first and second air-to-fuel ratios indicative of conditions whereat maximum combustion occurs in said vehicle.

90. The system of claim 89 wherein said ECM cycles said engine about said selected air-to-fuel ratios.

91. The system of claim 90 wherein said system includes an EGO sensor for determining lambda signals, said ECM means using said lambda signals to set said first and second air-to-fuel ratios, said ECM means using said selected air-to-fuel ratios to adjust said lambda signals from said EGO sensor.

92. The system of claim 50 wherein said first and second set air-to-fuel ratios define a lean burn combustion condition of said vehicle.

93. The system of claim 92 wherein said interpolating means detects the amplitude of the first order frequency component of said spectrum and said ECM controls said air-to-fuel ratio at said lean burn condition by the amplitude of said detected first order frequency component.

60. A method for monitoring and/or controlling a function of an internal combustion engine emitting exhaust gases in a vehicle comprising the steps of:

a) cycling said engine between first and second extreme operating conditions to produce a generally consistently varying exhaust gas composition of specific emissions which is repeatedly reproduced from one cycle to the next;

b) sensing energy from specific emissions in said exhaust gases reacting at a reactor area within a calorimetric sensor continuously receiving a slip stream of said exhaust gases;

c) generating an electrical calorimetric signal indicative of said specific emission concentrations and correlated to the frequency at which said engine is cycled;

d) mathematically interpolating said calorimetric signal to determine a function signal indicative of a current operating state of said engine; and

e) controlling and/or monitoring a function of said engine by said function signal.

61. The method of claim 60 wherein said operating condition is one or more operating conditions selected from the group consisting of of i) valve timing, ii) spark timing, iii) speed, iv) exhaust gas recirculation, v) injection timing, vi) air to fuel ratio, vii) mass air flow, viii) manifold air pressure and ix) perturbation frequency.

62. The method of claim 60 wherein said function of said engine monitored and/or controlled by said function signal is one or more functions selected from the group consisting of a) controlling the air to fuel ratio supplied by the fuel injectors to said engine, b) controlling set amounts of exhaust gases recirculated to the combustion chambers of said engine c) controlling engine timing, d) controlling combustion air pressure and/or flow supplied to said fuel injectors, e) controlling frequency of said cycling step, f) calibrating control devices on said vehicle when said engine is operating at set lambda values, g) monitoring concentrations of one or more specific gaseous emissions produced by said engine, h) monitoring the efficiency of the catalytic converter, i) ascertaining which pollution control system on the vehicle has failed when concentrations of specific emissions have exceeded regulatory standards, j) monitoring emissions produced during operation of said vehicle to determine if said vehicle is in compliance with emission requirements for specific drive cycles and k) controlling said operating condition of said engine so that the catalytic converter on the vehicle can convert specific gaseous emissions to harmless gases in compliance with regulatory standards.

63. The method of claim 60 wherein said step of mathematically interpolating said calorimetric signal includes the steps of digitizing said calorimetric signal a data signal, transforming said data signal into a frequency domain having a spectrum of frequency components, evaluating at least one of said frequency components in said spectrum correlated to the cycle frequency to determine said function signal.

64. The method of claim 61 further including said function of said engine monitored and/or controlled by said function signal is one or more functions selected from the group consisting of a) controlling the air to fuel ratio supplied by the fuel injectors to said engine, b) controlling set amounts of exhaust gases recirculated to the combustion chambers of said engine c) controlling engine timing, d) controlling combustion air pressure and/or flow supplied to said fuel injectors, e) controlling frequency of said cycling step, f) calibrating control devices on said vehicle when said engine is operating at set lambda values, g) monitoring concentrations of one or more specific gaseous emissions produced by said engine, h) monitoring the efficiency of the catalytic converter, i) ascertaining which pollution control system on the vehicle has failed when concentrations of specific emissions have exceeded regulatory standards, j) monitoring emissions produced during operation of said vehicle to determine if said vehicle is in compliance with emission requirements for specific drive cycles and k) controlling said operating condition of said engine so that the catalytic converter on the vehicle can convert specific gaseous emissions to harmless gases in compliance with regulatory standards.

65. The method of claim 64 further including said step of mathematically interpolating said calorimetric signal includes the steps of digitizing said calorimetric signal a data signal, transforming said data signal into a frequency domain having a spectrum of frequency components, evaluating at least one of said frequency components in said spectrum correlated to the cycle frequency to determine said function signal.

66. The method of claim 62 further including said step of mathematically interpolating said calorimetric signal includes the steps of digitizing said calorimetric signal a data signal, transforming said data signal into a frequency domain having a spectrum of frequency components, evaluating at least one of said frequency components in said spectrum correlated to the cycle frequency to determine said function signal.

67. The method of claim 61 further including said step of mathematically interpolating said calorimetric signal includes the steps of digitizing said calorimetric signal a data signal, transforming said data signal into a frequency domain having a spectrum of frequency components, evaluating at least one of said frequency components in said spectrum correlated to the cycle frequency to determine said function signal.

68. The method of claim 60 wherein said cycling step is at frequencies such that heat reactions of said exhaust gases at said reactor area of said sensor do not reach steady state at first and second conditions.

69. The method of claim 68 further including the steps of converting only HC and H₂ or HC, CO and H₂ emissions in said exhaust gases by a light-off catalytic converter closely adjacent said engine, and providing a selective catalyst on said reactor area promoting processes wherein energy is liberated or consumed for HC and H₂ or HC, CO and H₂ or CO and H₂ only so that said calorimetric signal is indicative of HC and H₂ or HC, CO and H₂ or CO and H₂ gaseous emissions in said exhaust gases.

70. The method of claim 68 wherein said step of interpolating determines from the amplitude of said calorimetric signal during said cycles the concentration of HC and H₂ or HC, CO and H₂ or CO and H₂ emissions present in said exhaust gases and further including the steps of e1)comparing said calculated concentrations to a stored value indicative of a regulatory emission standard or a catalytic converter efficiency value;

e2) changing said operating conditions to cause said engine to produce different concentrations of specific gaseous emissions in said exhaust which can be converted by said light-off catalytic converter and e3) triggering a warning mechanism that said vehicle is not meeting emission standards should step e2 be unsuccessful.

71. The method of claim 70 wherein said step of changing said operating conditions includes one or more of the following steps:

ai) changing the ratio of fuel to air supplied to the combustion chambers of said engine;

aii) changing the set ratio of exhaust gas metered into said combustion chambers of said engine;

aiii) changing the spark timing of said engine, aiv) changing the cycle frequency;

av) changing the lambda perturbation amplitude and avi) changing mass air flow and/or manifold air pressure of the combustion air metered to the combustion chambers of said engine.

72. The method of claim 68 wherein said function signal controls the ratio of combustion air to fuel metered to the combustion chambers of said engine.

73. The method of claim 68 wherein said function signal controls the ratio of exhaust gas recirculated to the combustion chambers of said engine during each operating condition of said engine.

74. The method of claim 68 further including the steps of converting specific emissions by a catalytic converter through which said exhaust gases pass, said sensing occurring downstream of said catalytic converter;

providing an oxygen sensor upstream of said catalytic converter, determining by said oxygen sensor the oxygen present in said exhaust gases, cycling said engine at various set operating conditions until said calorimetric sensor determines that said engine is operating at a combustion air to fuel ratio having a lambda value near 1 and calibrating said oxygen sensor at said operating condition whereby drift in said oxygen sensor attributed to aging is accounted for.

75. The method of claim 68 wherein said operating conditions comprise first and second ratios of combustion air to fuel and method further includes the steps of maintaining said first and second set ratios of combustion air to fuel for all combustion chambers of said engine except for one selected fuel injector, varying the fuel supplied by said selected fuel injector during said first and second conditions for a plurality of cycles and calibrating said selected fuel injector by said function signal.

76. The method of claim 68 further including the steps of providing an oxygen sensor adjacent said calorimetric sensor to produce an oxygen signal;

mathematically interpolating the amplitude of i) said oxygen signal to determine the air to fuel ratio at which combustion air and fuel are supplied to the combustion chamber of said engine and ii) said calorimetric signal to determine the concentration of specific emissions in said exhaust gas; and

adjusting the air to fuel ratio of the vehicle controlled by said oxygen sensor when said calorimetric signal reaches set values.

77. In a process in which a fluid having reaction characteristics affected by said process is used in said process, the improvement comprising:

a) continuously extracting a slip stream of said fluid used in said process;

b) cyclically varying select reaction components of said fluid, at least in said slip stream, between two set limits;

c) contacting said slip stream with said cyclically varying reaction components at a reaction surface to cause a transformation of said reaction components whereby energy is cyclically liberated or consumed;

d) sensing said energy resulting from step (c) to develop an electrical sensor signal indicative of said transformations; and

e) interpolating said signal to monitor and/or control said process.

78. The process of claim 77 wherein said reaction components of said fluid are cyclically varied while said process is being performed.

79. The process of claim 77 wherein said reaction components of said fluid are cyclically varied at said reaction area.

80. The process of claim 77 wherein said interpolating step further includes the steps of

digitizing said electrical signal into a data signal,

transforming said data signal into a frequency domain having a spectrum of frequency components,

analyzing at least one of said frequency components in said spectrum correlated to the cycle frequency to operate and/or control the system.

81. The process of claim 80 wherein said fluid is a gas, said energy reaction is a heat flux reaction, and said signal is indicative of a heat measurement.

82. The process of claim 81 wherein said process is the combustion of fuel and air in an internal combustion engine and said reaction characteristics are selected emission concentrations in the exhaust gas produced by said combustion process.

83. An on-board monitoring and/or control system for use and in combination with a vehicle having an internal combustion engine with fuel injectors emitting during operation, exhaust gases;

said system comprising;

a) an electronic control module causing said engine to cycle between first and second extreme operating conditions to produce an exhaust gas having generally, consistently varying concentrations of specific emissions during each cycle which are repeatedly reproduced from cycle to cycle;

b) a calorimetric sensor producing a continuous calorimetric signal indicative of the changes in the exhaust gas composition during each cycle;

c) a digital signal processor generating a function signal by analyzing the changes in said calorimetric signal; and

d) said electronic control module applying said function signal to a control on said vehicle for monitoring and/or controlling a function of said vehicle.