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To fulfill ever increasingly stringent emission regulations, a great many studies on engine control and catalytic converter performance have been made. Topics of great interest in this area, to name a few, include: the relationship between catalyst light-off time and air-fuel (A/F) ratio; the relationship between forced A/F ratio modulation and catalyst efficiency; the effects of phase-shifted A/F ratio modulation between banks of a dual bank engine, or among cylinders of a single manifold engine on catalyst efficiency; and methods of modeling and measuring the oxygen storage capacity of a catalytic converter by rich-lean transition, A/F ratio sweeping, or other on-line estimation methods. To undertake this type of research, an engine control system with necessary functions, especially with very flexible A/F ratio control capabilities, is needed.

The Electronic Throttle Control (ETC) system is more and more used and increasingly becoming a standard part of the engine. It controls the amount of air intake into the cylinders by precisely positioning the throttle plate at the desired opening. An ETC system provides the possibility of improving the overall engine and vehicle performance because with such a mechanism, the engine controller can decide and set the throttle position not only based on driver intention, but also taking into consideration the specific engine operation mode information, such as safety factors, emission constraints, etc. After the throttle position target is determined, the requirement for the ETC system is that the throttle plate should achieve the commanded position as accurately and as quickly as possible. In many cases the controller is designed by first establishing a model of the electronic throttle system using experimental identification.

To meet the ever increasing requirements in the areas of performance, fuel economy and emission, more and more subsystems and control functions are being added to modern engines. This leads to a quick increase in the number of control parameters and consequently dramatic time and cost increase for engine calibration. To deal with this problem, the automotive industry has turned to model-based calibration for a solution. Model-based calibration is a method that uses modern Design of Experiments (DoE), statistical modeling and optimization techniques to efficiently produce high quality calibrations for engines. There are two major enablers for carrying out this method - fully automated engine control and measurement system, and advanced mathematical tools for DoE, modeling and optimization.

Ever increasing requirements for vehicle performance, fuel economy and emissions have been driving the development and adoption of various types of hybrid powertrains. There are many different configurations of hybrid powertrains, which may include such components as engine, generator and inverter, battery pack, ultracapacitor, traction motor and inverter, transmission, and various control units. A hardware-in-the loop (HiL) testing solution that is flexible enough to accommodate different types of hybrid powertrain configurations and run a range of test scenarios is needed to support on-going development activities in this field. This paper describes the design and implementation of such a HiL testing system. The system is centered on a high performance, real-time controller that runs powertrain, driveline, vehicle, and driver models.

Variable compression ratio and variable displacement technologies are adopted in internal combustion engines because these features provide further degrees of freedom to optimize engine performance for various operating conditions. This paper focuses on a multiple-link mechanism that realizes variable compression ratio and displacement by varying the piston motion, specifically the Top Dead Center (TDC) and Bottom Dead Center (BDC) positions relative to the crankshaft. It is determined that a major requirement for the design of this mechanism is when the control action changes monotonically over its whole range, the compression ratio and the displacement should change in opposite directions monotonically. This paper presents an approach on how to achieve multiple-link mechanism geometric designs that fulfill this requirement.