US5535135A
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US
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State estimator based exhaust gas chemistry measurement system and method
Assignee: Aumovio Systems Inc
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Filing: 1993-08-24
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Granted: 1996-07-09
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Expires: 2013-08-24
Abstract
Abstract A system, and a corresponding method, for measuring a chemical concentration of a gas exhausted from exhaust ports (409, 413) of a multi-cylinder internal combustion engine (401) includes a gas sensing device. This device (419) is preferably a UEGO (Universal Exhaust Gas Oxygen) sensor. The gas exhausted is present in a substantially stable chemical concentration (706, 718) at a collection point (420) during intervals (738, 742) of engine angular rotation corresponding to the exhaust cycles. The UEGO sensor (419) measures the gas exhausted from the exhaust ports (409, 413) and provides a sensory output signal (743) that, during the intervals (738, 742) of engine angular rotation corresponding to each of the exhaust cycles, approaches (737, 741) a substantially stable value representative of the chemical concentration of the gas (706, 718) exhausted during the associated exhaust cycle. The sensory output signal (743) is coupled to an engine control system (431) that is executing signal reconstruction method steps (500, 600). These signal reconstruction steps (500, 600) are preferably based on a Kalman-Bucy state estimator in which a constituent gas signal Poe (745) that has a substantially constant amplitude during the intervals (738, 742), is reconstructed by the Kalman-Bucy state estimation reconstruction process (500, 600). The described improved method, and system, can compensate for the static and dynamic temporal and spacial effects, characteristic of the multi-cylinder engine exhaust system and the difference in sensory response to rich and lean exhaust gases, of the UEGO (419) sensor.
Inventors
- 👤 Kevin J. Bush
- 👤 Sanjay Dua
- 👤 Neil J. Adams
- 👤 Craig R. Markyvech
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:13
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/008; F02D41/02; F02D41/14; F02D41/1401; F02D41/1438; F02D41/1473; F02D41/1477; F02D41/1481; G; G01; G01M; G01M15/00; G01M15/04; G01M15/10; G01M15/102; G01M15/104; F02D2041/1412; F02D2041/1413; F02D2041/1415; F02D2041/1416; F02D2041/1417; F02D2041/1433; F02D41/0085; F02D41/1444; F02D41/1454; F02D41/1456
Claims Analysis
Total Claims: 59
Claim 1
Independent Claim
111 words
A system for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, said system comprising: a gas chemistry sensor, responsively coupled to the collection point, for measuring the gas exhausted from each of the plurality of exhaust ports and for providing a sensory output signal dependent thereon; and a state estimator, comprising state estimation coefficients associated with an engineering model of said gas chemistry sensor, the state estimator responsively coupled to the sensory output signal provided by said gas chemistry sensor, wherein said state estimator provides a constituent gas signal in response to the sensory output signal.
Claim 2
Independent Claim
111 words
A system for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, said system comprising: a gas chemistry sensor, responsively coupled to the collection point, for measuring the gas exhausted from each of the plurality of exhaust ports and for providing a sensory output signal dependent thereon; and a state estimator, comprising state estimation coefficients associated with an engineering model of said gas chemistry sensor, the state estimator responsively coupled to the sensory output signal provided by said gas chemistry sensor, wherein said state estimator provides a constituent gas signal in response to the sensory output signal.
Claim 3
Dependent Claim
70 words
A system in accordance with claim 1 wherein said signal reconstruction means comprises a periodic timer, wherein said state estimation means is iterated responsive to the periodic timer, and wherein progressive iterations within each of the intervals provides a constituent gas signal converging towards an amplitude indicative of the stable chemical concentration of the gas exhausted during each of the intervals of engine angular rotation corresponding to the exhaust cycles.
Claim 4
Dependent Claim
54 words
A system in accordance with claim 1 wherein said signal reconstruction means further comprises means for determining an output sampling delay time from the commencement of each of the plurality of exhaust cycles, and wherein said signal reconstruction means provides the constituent gas signal coincident with an expiration of the output sampling delay time.
Claim 5
Dependent Claim
25 words
A system in accordance with claim 3 wherein the output sampling delay time is different for at least two of the plurality of exhaust cycles.
Claim 6
Dependent Claim
24 words
A system in accordance with claim 4 wherein said signal reconstruction means determines a normalized air-fuel ratio dependent on the determined constituent gas signal.
Claim 7
Dependent Claim
40 words
A system in accordance with claim 3 wherein each of the output sampling delay times are dependent on an exhaust runner path length between each of the at least two of the plurality of exhaust ports and the collection point.
Claim 8
Dependent Claim
60 words
A system in accordance with claim 3 wherein said means for determining an output sampling delay time comprises engine angular displacement determination means for determining which exhaust port of the plurality of exhaust ports of said multi-cylinder internal combustion engine is exhausting, and wherein said output sampling delay time is dependent on a geometric model of the determined exhausting port.
Claim 9
Dependent Claim
37 words
A system in accordance with claim 3 wherein said means for determining an output sampling delay time comprises means for determining engine speed and wherein said output sampling delay time is dependent on the determined engine speed.
Claim 10
Dependent Claim
37 words
A system in accordance with claim 3 wherein said means for determining an output sampling delay time comprises means for determining engine load and wherein said output sampling delay time is dependent on the determined engine load.
Claim 11
Dependent Claim
35 words
A system in accordance with claim 9 wherein said means for determining engine load comprises means for determining an air charge mass associated with a combustion process preceding each of the plurality of exhaust cycles.
Claim 12
Dependent Claim
21 words
A system in accordance with claim 10 wherein said means for determining air charge mass comprises a mass air flow sensor.
Claim 13
Dependent Claim
20 words
A system in accordance with claim 10 wherein said means for determining air charge mass comprises an absolute pressure sensor.
Claim 14
Dependent Claim
23 words
A system in accordance with claim 3 wherein said output sampling delay time is dependent on an integer multiple of the periodic timer.
Claim 15
Dependent Claim
106 words
A system in accordance with claim 1 wherein said signal reconstruction means further comprises means for predicting an exhaust gas oxygen concentration independent of said state estimation means, wherein the independently predicted exhaust gas oxygen concentration is provided as an a priori input to said state estimation means, and wherein responsive to the independently predicted exhaust gas oxygen concentration and the sensory output signal, provided by said gas chemistry sensory means, the signal reconstruction means provides a constituent gas signal that has an amplitude indicative of the stable chemical concentration of the gas exhausted during the intervals of engine angular rotation corresponding to the exhaust cycles.
Claim 16
Dependent Claim
43 words
A system in accordance with claim 14 further comprising engine control means for providing a fuel charge mass associated with a combustion process preceding each of the exhaust cycles, wherein said exhaust gas oxygen concentration is predicted dependent on the fuel charge mass.
Claim 17
Dependent Claim
32 words
A system in accordance with claim 15 wherein said exhaust gas oxygen concentration is predicted dependent on an air charge mass associated with a combustion process preceding each of the exhaust cycles.
Claim 18
Dependent Claim
62 words
A system in accordance with claim 14 wherein said signal reconstruction means further comprises means for determining an input estimate delay time from the commencement of each of the plurality of exhaust cycles, and wherein said signal reconstruction means provides the independently predicted exhaust gas oxygen concentration to said state estimation means coincident with an expiration of the input estimate delay time.
Claim 19
Dependent Claim
22 words
A system in accordance with claim 17 wherein said input estimate delay time expires at the commencement of each of the intervals.
Claim 20
Dependent Claim
25 words
A system in accordance with claim 17 wherein the input estimate delay time is different for at least two of the plurality of exhaust cycles.
Claim 21
Dependent Claim
40 words
A system in accordance with claim 17 wherein each of the input estimate delay times are dependent on an exhaust runner path length between each of the at least two of the plurality of exhaust ports and the collection point.
Claim 22
Dependent Claim
60 words
A system in accordance with claim 17 wherein said means for determining an input estimate delay time comprises engine angular displacement determination means for determining which exhaust port of the plurality of exhaust ports of said multi-cylinder internal combustion engine is exhausting, and wherein said input estimate delay time is dependent on a geometric model of the determined exhausting port.
Claim 23
Dependent Claim
37 words
A system in accordance with claim 17 wherein said means for determining an input estimate delay time comprises means for determining engine speed and wherein said input estimate delay time is dependent on the determined engine speed.
Claim 24
Dependent Claim
37 words
A system in accordance with claim 17 wherein said means for determining an input estimate delay time comprises means for determining engine load and wherein said input estimate delay time is dependent on the determined engine load.
Claim 25
Dependent Claim
35 words
A system in accordance with claim 23 wherein said means for determining engine load comprises means for determining an air charge mass associated with a combustion process preceding each of the plurality of exhaust cycles.
Claim 26
Dependent Claim
23 words
A system in accordance with claim 17 wherein said input estimate delay time is dependent on an integer multiple of the periodic timer.
Claim 27
Dependent Claim
50 words
A system in accordance with claim 1 wherein a different set of state estimation coefficients are selected responsive to a predetermined influence associated with the gas exhausted, and wherein, responsive to the selection of said different set of state estimation coefficients, said state estimation means provides the constituent gas signal.
Claim 28
Dependent Claim
24 words
A system in accordance with claim 26 wherein the influence associated with the gas exhausted corresponds to an amplitude of the constituent gas signal.
Claim 29
Dependent Claim
73 words
A system in accordance with claim 27 wherein rich state estimation coefficients are selected responsive to a first amplitude of the constituent gas signal, and a lean state estimation coefficients are selected responsive to a second amplitude of the constituent gas signal, wherein the sensory output signal of said gas chemistry sensory means is reconstructed in accordance with the selected state estimation coefficients and the constituent gas signal is provided in responsive thereto.
Claim 30
Dependent Claim
48 words
A system in accordance with claim 26 wherein said engineering model of said gas chemistry sensory means includes a model of said sensory means behavior associated with sensing hydrogen in said gas exhausted, and wherein the influence associated with the gas exhausted corresponds to the measurement of hydrogen.
Claim 31
Dependent Claim
50 words
A system in accordance with claim 26 wherein said engineering model of said gas chemistry sensory means includes a model of said sensory means behavior associated with sensing carbon monoxide in said gas exhausted, and wherein the influence associated with the gas exhausted corresponds to the measurement of carbon monoxide.
Claim 32
Dependent Claim
25 words
A system in accordance with claim 1 wherein another output signal, associated with the engineering model and distinct from the constituent gas signal is provided.
Claim 33
Dependent Claim
49 words
A system in accordance with claim 31 wherein said engineering model of said gas chemistry sensory means includes a model of said sensory means behavior associated with sensing hydrogen in said gas exhausted, and wherein the another output signal is representative of the hydrogen content in the gas exhausted.
Claim 34
Dependent Claim
51 words
A system in accordance with claim 31 wherein said engineering model of said gas chemistry sensory means includes a model of said sensory means behavior associated with sensing carbon monoxide in said gas exhausted, and wherein the another output signal is representative of the carbon monoxide content in the gas exhausted.
Claim 35
Dependent Claim
29 words
A system in accordance with claim 1 wherein said gas chemistry sensory means comprises an oxygen sensor and the constituent gas signal is oxygen concentration of said gas exhausted.
Claim 36
Dependent Claim
24 words
A system in accordance with claim 34 wherein said signal reconstruction means determines a normalized air-fuel ratio dependent on the determined constituent gas signal.
Claim 37
Dependent Claim
72 words
A system in accordance with claim 1 wherein said gas chemistry sensory means comprises a Universal Exhaust Gas Oxygen sensor, wherein said engineering model of said gas chemistry sensory means includes a model of said sensory means behavior associated with sensing partial pressure of oxygen in the detecting cavity, and wherein the another output signal is representative of the partial pressure of oxygen in the detecting cavity dependent on the gas exhausted.
Claim 38
Independent Claim
127 words
A system for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, said system comprising: gas chemistry sensory means, responsively coupled to the plurality of exhaust ports, for measuring the gas exhausted from each of the plurality of exhaust ports and for providing a linear sensory output signal responsive thereto; means for determining an output sampling delay time associated with each of the plurality of exhaust cycles; signal reconstruction means, responsively coupled to the linear sensory output signal, for providing a constituent gas signal coincident with an expiration of the output sampling delay time, wherein the constituent gas signal has an amplitude indicative of the gas exhausted during each of the exhaust cycles.
Claim 39
Independent Claim
127 words
A system for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, said system comprising: gas chemistry sensory means, responsively coupled to the plurality of exhaust ports, for measuring the gas exhausted from each of the plurality of exhaust ports and for providing a linear sensory output signal responsive thereto; means for determining an output sampling delay time associated with each of the plurality of exhaust cycles; signal reconstruction means, responsively coupled to the linear sensory output signal, for providing a constituent gas signal coincident with an expiration of the output sampling delay time, wherein the constituent gas signal has an amplitude indicative of the gas exhausted during each of the exhaust cycles.
Claim 40
Dependent Claim
25 words
A system in accordance with claim 37 wherein the output sampling delay time is different for at least two of the plurality of exhaust cycles.
Claim 41
Dependent Claim
60 words
A system in accordance with claim 38 wherein said means for determining an output sampling delay time comprises engine angular displacement determination means for determining which exhaust port of the plurality of exhaust ports of said multi-cylinder internal combustion engine is exhausting, and wherein said output sampling delay time is dependent on a geometric model of the determined exhausting port.
Claim 42
Dependent Claim
37 words
A system in accordance with claim 39 wherein said means for determining an output sampling delay time comprises means for determining engine speed and wherein said output sampling delay time is dependent on the determined engine speed.
Claim 43
Dependent Claim
37 words
A system in accordance with claim 40 wherein said means for determining an output sampling delay time comprises means for determining engine load and wherein said output sampling delay time is dependent on the determined engine load.
Claim 44
Dependent Claim
54 words
A system in accordance with claim 41 wherein said signal reconstruction means comprises state estimation means, wherein said state estimation means includes state estimation coefficients associated with an engineering model of said gas chemistry sensory means and wherein said state estimation means provides the constituent gas signal in response to the sensory output signal.
Claim 45
Dependent Claim
94 words
A system in accordance with claim 42 wherein said signal reconstruction means further comprises means for predicting an exhaust gas oxygen concentration independent of said state estimation means, wherein the independently predicted exhaust gas oxygen concentration is provided as an a priori input to said state estimation means, and wherein responsive to the independently predicted exhaust gas oxygen concentration and the sensory output signal, provided by said gas chemistry sensory means, the signal reconstruction means provides a constituent gas signal having an amplitude indicative of the gas exhausted during each of the exhaust cycles.
Claim 46
Dependent Claim
62 words
A system in accordance with claim 43 wherein said signal reconstruction means further comprises means for determining an input estimate delay time from the commencement of each of the plurality of exhaust cycles, and wherein said signal reconstruction means provides the independently predicted exhaust gas oxygen concentration to said state estimation means coincident with an expiration of the input estimate delay time.
Claim 47
Dependent Claim
22 words
A system in accordance with claim 44 wherein said input estimate delay time expires at the commencement of each of the intervals.
Claim 48
Dependent Claim
25 words
A system in accordance with claim 45 wherein the input estimate delay time is different for at least two of the plurality of exhaust cycles.
Claim 49
Dependent Claim
60 words
A system in accordance with claim 46 wherein said means for determining an input estimate delay time comprises engine angular displacement determination means for determining which exhaust port of the plurality of exhaust ports of said multi-cylinder internal combustion engine is exhausting, and wherein said input estimate delay time is dependent on a geometric model of the determined exhausting port.
Claim 50
Dependent Claim
37 words
A system in accordance with claim 47 wherein said means for determining an input estimate delay time comprises means for determining engine speed and wherein said input estimate delay time is dependent on the determined engine speed.
Claim 51
Dependent Claim
37 words
A system in accordance with claim 48 wherein said means for determining an input estimate delay time comprises means for determining engine load and wherein said input estimate delay time is dependent on the determined engine load.
Claim 52
Dependent Claim
35 words
A system in accordance with claim 49 wherein said means for determining engine load comprises means for determining an air charge mass associated with a combustion process preceding each of the plurality of exhaust cycles.
Claim 53
Dependent Claim
50 words
A system in accordance with claim 42 wherein a different set of state estimation coefficients are selected responsive to a predetermined influence associated with the gas exhausted, and wherein, responsive to the selection of said different set of state estimation coefficients, said state estimation means provides the constituent gas signal.
Claim 54
Dependent Claim
24 words
A system in accordance with claim 51 wherein the influence associated with the gas exhausted corresponds to an amplitude of the constituent gas signal.
Claim 55
Dependent Claim
73 words
A system in accordance with claim 52 wherein rich state estimation coefficients are selected responsive to a first amplitude of the constituent gas signal, and a lean state estimation coefficients are selected responsive to a second amplitude of the constituent gas signal, wherein the sensory output signal of said gas chemistry sensory means is reconstructed in accordance with the selected state estimation coefficients and the constituent gas signal is provided in responsive thereto.
Claim 56
Independent Claim
203 words
A method for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, wherein the gas exhausted is present at a collection point in a stable chemical concentration during intervals of engine angular rotation corresponding to the exhaust cycles, said method comprising the steps of: measuring the gas exhausted from each of the plurality of exhaust ports present at the collection point, and for providing a sensory output signal that, during the intervals of engine angular rotation, approaches a value representative of the stable chemical concentration of the gas exhausted; and reconstructing the stable chemical concentration of the gas exhausted from the sensory output signal provided in said step of measuring by predicting an exhaust gas oxygen concentration and providing a predicted exhaust gas oxygen concentration as an a priori input to the reconstructing step, wherein responsive to the predicted exhaust gas oxygen concentration, and the sensory output signal provided in said step of measuring, the step of reconstructing provides a constituent gas signal that has an amplitude indicative of the stable chemical concentration of the gas exhausted during the intervals of engine angular rotation corresponding to the exhaust cycles.
Claim 57
Independent Claim
203 words
A method for measuring a chemical concentration of a gas exhausted during exhaust cycles from a plurality of exhaust ports of a multi-cylinder internal combustion engine, wherein the gas exhausted is present at a collection point in a stable chemical concentration during intervals of engine angular rotation corresponding to the exhaust cycles, said method comprising the steps of: measuring the gas exhausted from each of the plurality of exhaust ports present at the collection point, and for providing a sensory output signal that, during the intervals of engine angular rotation, approaches a value representative of the stable chemical concentration of the gas exhausted; and reconstructing the stable chemical concentration of the gas exhausted from the sensory output signal provided in said step of measuring by predicting an exhaust gas oxygen concentration and providing a predicted exhaust gas oxygen concentration as an a priori input to the reconstructing step, wherein responsive to the predicted exhaust gas oxygen concentration, and the sensory output signal provided in said step of measuring, the step of reconstructing provides a constituent gas signal that has an amplitude indicative of the stable chemical concentration of the gas exhausted during the intervals of engine angular rotation corresponding to the exhaust cycles.
Claim 58
Dependent Claim
61 words
A method in accordance with claim 54 wherein said step of reconstructing further comprises the step of: determining an input estimate delay time from the commencement of each of the plurality of exhaust cycles, wherein the step of predicting provides the predicted exhaust gas oxygen concentration to the step of reconstructing coincident with an expiration of the input estimate delay time.
Claim 59
Dependent Claim
24 words
A method in accordance with claim 54 further comprising a step of determining a normalized air-fuel ratio dependent on the determined constituent gas signal.
References Cited (Backward Citations)
US3961477A
Cited
US4000614A
Cited
US3939654A
Cited
US4253302A
Cited
US4251990A
Cited
US4362605A
Cited
US4272329A
Cited
US4498968A
Cited
US4761950A
Cited
US4719895A
Cited
US4841934A
Cited
US4987888A
Cited
US5093792A
Cited
US5050084A
Cited
US5083427A
Cited
EP0444783A1
Cited
US5349932A
Cited
US5273019A
Cited
US5094213A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-07-09 | 2000-01-08 | 2000-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-07-09 | 2004-01-08 | 2004-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-07-09 | 2008-01-08 | 2008-07-09 | $7700.00 | Window Closed / Lapsed |