Abstract: A method comprising adjusting a fuel injection amount based on a fractional oxidation state of a catalyst, the fractional oxidation state based on reaction rates of grouped oxidant and reductant exhaust gas species throughout a catalyst and a low-dimensional physics-based model derived from a detailed two-dimensional model to obtain a one-dimensional model averaged over time and space that accounts for diffusion limitations in the washcoat and accurately predicts emissions during cold start.

Abstract: A method for monitoring an exhaust gas sensor coupled in an engine exhaust is provided. In one embodiment, the method comprises indicating exhaust gas sensor degradation based on characteristics of a distribution of extreme values of a plurality of sets of lambda differentials collected during selected operating conditions. In this way, the exhaust gas sensor may be monitored in a non-intrusive manner.

Abstract: Methods and systems are provided for an engine including a humidity sensor. Degradation of the humidity sensor may be determined based on a change in intake air relative humidity as compared to a change in intake air temperature or pressure, under selected conditions. An amount of exhaust gas recirculated to an engine intake is adjusted differently based on whether the humidity sensor is degraded or functional.

Abstract: Methods and systems are disclosed for controlling an exhaust gas recirculation valve in an engine by determining errors in exhaust backpressure estimates and adapting EGR flow estimations based on these errors to meet target EGR dilutions in the engine. In one example approach, a method comprises adjusting valve position based on desired EGR flow and estimated EGR flow, where the estimated flow is based on estimated exhaust backpressure, and the estimated exhaust backpressure is updated based on errors between actual and desired intake oxygen concentration.

Abstract: A method for monitoring an exhaust gas sensor coupled in an engine exhaust is provided. In one embodiment, the method comprises indicating exhaust gas sensor degradation based on a time delay and line length of each sample of a set of exhaust gas sensor responses collected during a commanded change in air-fuel ratio. In this way, the exhaust gas sensor may be monitored utilizing robust parameters in a non-intrusive manner.

Abstract: Route planning for road vehicles is performed taking into account a ride quality that results from the roadway conditions along road segments on a route. A plurality of vehicles equipped with controlled suspensions calculate ride quality indices as the vehicles move over a plurality of road segments. The plurality of vehicles transmit the ride quality indices tagged with respective geographic coordinates to an aggregating server. The aggregating server determines a composite ride quality index for each road segment. A subscriber generates a route planning request identifying an origin and a destination. At least one potential route is identified between the origin and the destination comprised of selected road segments. A route ride quality index is determined in response to the selected road segments, and the potential route and the route ride quality index are presented to the subscriber for selection.

Abstract: Various approaches are described for air-fuel ratio control in an engine. In one example, a method include adjusting fuel injection from an anticipatory controller responsive to exhaust oxygen feedback of an exhaust gas sensor positioned upstream of an exhaust catalyst, the anticipatory controller including a first integral term and a second integral term, the second integral term correcting for past fuel disturbances. In this way, it is possible to provide fast responses to errors via the anticipatory controller, while corrected known past fueling errors, on average, via the second integral term.

Abstract: Methods and systems are provided for an engine including a humidity sensor. Degradation of the humidity sensor may be determined based on a change in intake air relative humidity as compared to a change in intake air temperature or pressure, under selected conditions. An amount of exhaust gas recirculated to an engine intake is adjusted differently based on whether the humidity sensor is degraded or functional.

Abstract: A method of monitoring an exhaust gas sensor coupled in an engine exhaust is provided. The method comprises indicating exhaust gas sensor degradation based on a difference between a first set of estimated parameters of a rich operation model and a second set of estimated parameters of a lean operation model, the estimated parameters based on commanded lambda and determined lambda values collected during selected operating conditions. In this way, sensor degradation may be indicated with data collected in a non-intrusive manner.

Abstract: Methods and systems are provided reusing processed sensor data to identify multiple types of sensor degradation. In one example, a central peak of a distribution, such as a generalized extreme value distribution, of sensor readings is re-used to identify asymmetric sensor degradation and stuck in-range sensor degradation.

Abstract: Methods and systems are disclosed for controlling an exhaust gas recirculation valve in an engine by determining errors in exhaust backpressure estimates and adapting EGR flow estimations based on these errors to meet target EGR dilutions in the engine. In one example approach, a method comprises adjusting valve position based on desired EGR flow and estimated EGR flow, where the estimated flow is based on estimated exhaust backpressure, and the estimated exhaust backpressure is updated based on errors between actual and desired intake oxygen concentration.

Abstract: A method for monitoring an exhaust gas sensor coupled in an engine exhaust is provided. In one embodiment, the method comprises indicating exhaust gas sensor degradation based on a time delay and line length of each sample of a set of exhaust gas sensor responses collected during a commanded change in air-fuel ratio. In this way, the exhaust gas sensor may be monitored utilizing robust parameters in a non-intrusive manner.

Abstract: Methods and systems are provided for converting an asymmetric degradation response of an exhaust gas sensor to a more symmetric degradation response. In one example, a method includes adjusting fuel injection responsive to a modified exhaust oxygen feedback signal from an exhaust gas sensor, the modified exhaust oxygen feedback signal modified by transforming an asymmetric response of the exhaust gas sensor to a more symmetric response. Further, the method may include adjusting one or more parameters of an anticipatory controller of the exhaust gas sensor based on the modified symmetric response.

Abstract: A method is provided for monitoring an emission device coupled to an engine. In one example approach, the method comprises: following a deceleration fuel shut-off duration, indicating degradation of the emission device based on an amount of rich products required to cause a sensor to become richer than a threshold. The amount of rich products required may be correlated to an amount of oxygen stored in the emission device.

Abstract: Methods and systems are provided for an engine including a humidity sensor. Degradation of the humidity sensor may be determined based on a change in intake air relative humidity as compared to a change in intake air temperature or pressure, under selected conditions. An amount of exhaust gas recirculated to an engine intake is adjusted differently based on whether the humidity sensor is degraded or functional.

Abstract: Methods and systems are provided for an engine coupled capacitance-based humidity sensor. Degradation of the humidity sensor may be determined based on humidity readings while flowing gasses into an engine intake air downstream of the humidity sensor and upstream of a compressor change by less than a first threshold while pressure at the sensor changes greater then a second threshold. The variation in pressure can be changed by adjusting a throttle upstream and downstream of the compressor based on whether the humidity sensor is degraded or functional.

Abstract: A diagnostic method for a capacitive humidity sensor comprising a heater, and a capacitance-sensing element that individually indentifies heater, temperature-sensing element, or capacitance-sensing element degradation. By this method, individual elements of the sensor may be replaced or compensated for to allow for further operation.

Abstract: A method of monitoring catalyst performance may comprise applying a set of parameter readings for a given sample to a support vector machine to generate a classification output, clustering the set of parameter readings to reduce a number of support vectors, computing a total fuel mass following a deceleration fuel shut-off event and an exhaust gas oxygen sensor switch and indicating catalyst degradation based on the total fuel mass.

Abstract: Embodiments for adjusting fuel injection are provided. In one example, a method comprises adjusting fuel injection based on fuel concentration in an engine intake manifold, and during idle and when EGR is disabled, adjusting fuel injection based on the fuel concentration and a fuel pushback amount. In this way, fuel injection may be adjusted based on fuel concentration in the intake manifold.

Abstract: A diagnostic method for an engine having a valve for controlling dilution of intake air. The method comprises, during engine fueling, indicating a degradation of the valve when the valve is commanded closed but sensor output corresponds to an oxygen level below that of air. The method further comprises, absent engine fueling, indicating degradation of the sensor when the valve is commanded closed but the sensor output corresponds to an oxygen level below that of air.