Abstract: A system for controlling exhaust emissions produced by an internal combustion engine includes an engine controller having an emission manager configured to produce a base emission level cap command, corresponding to a maximum allowable emission level of the engine, as a function of at least altitude and ambient temperature. The emission manager may also include one or more auxiliary emission control devices (AECDs), and the emission manager is further operable in such cases to determine a maximum allowable emission level associated with each active AECD. A final emission level cap command is determined as a function of the base emission level cap command and the maximum allowable emission level associated with each active AECD. The emission manager is further operable to produce a protection state data structure that includes information relating to the operational status of each AECD.

Abstract: A combustion manager portion of an engine controller is responsive to ambient air density and engine temperature signals to schedule charge flow and EGR fraction commands. The combustion manager includes a data structure determination block operable to select an appropriate engine speed/engine fueling data structure based on air density and engine temperature information as well as on desired emissions level and engine operating state (i.e., steady state or transient) information. Charge flow and EGR fraction determination blocks are, in turn, responsive to current engine speed and engine fueling information to produce compute the EGR fraction and charge flow commands as a function of the selected engine speed/engine fueling data structures.

Abstract: A system for protecting an internal combustion engine employing cooled recirculated exhaust gas (EGR) from excessive condensation includes an auxiliary emission control device (AECD) operable to determine when engine operating conditions correspond to a condensing condition resulting in condensation of water at the outlet of the EGR cooler and/or within the intake manifold or intake conduit of the engine. When such conditions occur, the AECD is operable to close the EGR valve and monitor engine operating conditions. When engine operating conditions no longer correspond to the condensing condition, control of the EGR valve is restored to an air handling system associated with the engine.

Abstract: A combustion manager portion of an engine controller is responsive to ambient air density and engine temperature signals to schedule charge flow and EGR fraction commands. The combustion manager includes a data structure determination block operable to select an appropriate engine speed/engine fueling data structure based on air density and engine temperature information as well as on desired emissions level and engine operating state (i.e., steady state or transient) information. Charge flow and EGR fraction determination blocks are, in turn, responsive to current engine speed and engine fueling information to produce compute the EGR fraction and charge flow commands as a function of the selected engine speed/engine fueling data structures.

Abstract: A system for controlling exhaust emissions produced by an internal combustion engine includes an engine controller having an emission manager configured to produce a base emission level cap command, corresponding to a maximum allowable emission level of the engine, as a function of at least altitude and ambient temperature. The emission manager may also include one or more auxiliary emission control devices (AECDs), and the emission manager is further operable in such cases to determine a maximum allowable emission level associated with each active AECD. A final emission level cap command is determined as a function of the base emission level cap command and the maximum allowable emission level associated with each active AECD. The emission manager is further operable to produce a protection state data structure that includes information relating to the operational status of each AECD.

Abstract: A system is provided for estimating engine exhaust temperature in accordance with an exhaust temperature model based on a number of engine operating parameters. In one embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, mass charge flow, default fuel command parameters, and a first set of model constants. In an alternative embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, intake manifold pressure, mass charge flow, default fueling parameters, and a second set of model constants including a lower heating value of fuel constant.

Abstract: A system and method for controlling an engine or machine at a remote unit from a central office, which may be a fixed location, contemplates a transmit/receive interface connected to the computer or microprocessor of the engine or machine controller. This interface is integrated with a communications module that is configured to establish communications with a World Wide Web server on the Internet. A similar system is established at the location of the central office connected to a computer controlled by a fleet owner/operator, for example. The fleet owner can upload machine control data or machine control application software to an intermediate digital file storage maintained by the Web server via the Internet. This data or application software can be accessed and downloaded at any time by the remote operator without any direct interface or communication with the central office.

Abstract: A charge limit manager arbitrates between desired EGR system and/or turbocharger behavior and the actual capabilities of EGR system and/or turbocharger control mechanisms under current operating conditions. In one embodiment, the charge limit manager includes three limiter blocks producing offset signals as separate functions of turbocharger compressor outlet temperature, turbocharger speed and pressure differential (&Dgr;P) across an EGR valve. A charge limit selector block is responsive to the offset values produced thereby, and also to commanded values of charge flow and EGR fraction as well as operating values of EGR valve position and &Dgr;P, to limit the charge flow and EGR fraction commands to controllable values. These values are preferably subtracted from actual or estimated values of charge flow and EGR fraction to produce charge flow and EGR fraction error values for use in controlling one or more EGR system and/or turbocharger swallowing capacity/efficiency control mechanisms.

Abstract: A system is provided for estimating engine exhaust temperature in accordance with an exhaust temperature model based on a number of engine operating parameters. In one embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, mass charge flow, default fuel command parameters, and a first set of model constants. In an alternative embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, intake manifold pressure, mass charge flow, default fueling parameters, and a second set of model constants including a lower heating value of fuel constant.

Abstract: A charge limit manager arbitrates between desired EGR system and/or turbocharger behavior and the actual capabilities of EGR system and/or turbocharger control mechanisms under current operating conditions. In one embodiment, the charge limit manager includes three limiter blocks producing offset signals as separate functions of turbocharger compressor outlet temperature, turbocharger speed and pressure differential (&Dgr;P) across an EGR valve. A charge limit selector block is responsive to the offset values produced thereby, and also to commanded values of charge flow and EGR fraction as well as operating values of EGR valve position and &Dgr;P, to limit the charge flow and EGR fraction commands to controllable values. These values are preferably subtracted from actual or estimated values of charge flow and EGR fraction to produce charge flow and EGR fraction error values for use in controlling one or more EGR system and/or turbocharger swallowing capacity/efficiency control mechanisms.

Abstract: A system is disclosed for estimating the mass flow of recirculated exhaust gas (EGR) from an exhaust manifold to an intake manifold of an internal combustion engine via an EGR conduit disposed therebetween and a fraction of EGR attributable to a mass of charge flow entering the intake manifold. An engine controller is responsive to current values of various combinations of the engine exhaust temperature (ETE), intake manifold pressure (IMP), differential pressure (&Dgr;P) across an EGR valve, and EGR valve position (EGRP) to determine an estimate of EGR mass flow. The controller is further operable to estimate EGR fraction as a function of the estimated EGR mass flow value, mass flow of charge entering the intake manifold, and engine speed.

Abstract: A system for decoupling EGR flow and turbocharger swallowing capacity/efficiency control mechanisms includes a multiple-input multiple-output (MIMO) transform manager coupled to one or more of an EGR valve, an exhaust throttle and a variable geometry turbocharger (VGT) actuator of an internal combustion engine. The MIMO transform manager is responsive to commanded charge flow and EGR fraction parameters to decouple the EGR/exhaust throttle and VGT control parameters such that these control mechanisms may be controlled individually and independently of each other. One transform output is provided to a first compensator for controlling EGR flow and/or exhaust throttle operation as a function of charge flow error. The other transform output is provided to a second independent compensator for controlling VGT operation also as a function of charge flow error.

Abstract: A system for controlling air flow to an engine cooling system includes a control computer responsive to a number of engine and/or engine accessory operating conditions, and to various engine operational states to control operation of an engine cooling device. The engine operational states are each a function of at least engine fueling commands and include a "free energy" state corresponding to zero fueling, an "absorbing additional torque" state corresponding to zero fueling and activation of either service brakes or engine brakes, and a "needs additional torque" state corresponding to a rapid positive change in fueling, recent gear shifting to the lower gears of the transmission with fueling above a predefined level or a high rate of change in fueling rate. All other engine operational states are defined as a don't care state.

Abstract: A system and method for air compressor control wherein the air compressor is loaded only when engine activities require it to be loaded or when free engine power is available to operate the compressor. An air compressor system is an engine-driven, piston-type compressor which operates in a loaded and an unloaded mode and provides air to a vehicle's air powered devices, such as service brakes, air suspension, windshield wipers, etc. The operating mode of the compressor is controlled by a pressure activated air governor which applies an air signal when pressure in a reservoir reaches a set level that activates a cap valve on an unloader stopping the air compressor. When the air pressure in the reservoir drops below a lower set pressure or when energy is "free," such as during downhill operations, the air governor exhausts the air signal allowing the air compressor to resume operation.

Abstract: The present invention allows the vehicle to be operated at higher than normally desired speeds during periods when there is a legitimate need for increased performance, such as downshifting in order to aid in climbing an uphill grade or accelerating with the goal of upshifting. Like the prior art systems, the present invention also imposes a maximum vehicle speed for all non-top gears, but only during steady state conditions (defined as a light engine load existing for a predetermined period of time). During transient conditions (discerned by recognizing gear changes and by high engine load conditions), the control system of the present invention provides lenience from the normal maximum vehicle speed limits for non-top gears. Such lenience provides for increased vehicle performance during periods when it is legitimately needed by the driver.