Engine models that are used for nonlinear diesel engine control, state estimation, and model-based diagnostics are presented in this paper. By collecting, modifying, and adding to current available engine modeling techniques, two diesel engine models, a mean torque production model and a cylinder-by-cylinder model, are summarized for use in the formulation of control and state observation algorithms. In the cylinder-by-cylinder model, a time-varying crankshaft inertia model is added to a cylinder pressure generator to simulate engine speed variations due to discrete combustion events. Fuel injection timing and duration are control inputs while varying engine speed, cylinder pressure, and indicated torque are outputs from simulation. These diesel engine models can be used as engine simulators and to design diesel engine controllers and observers.

There is considerable interest in coordinated automotive engine/transmission control to smooth shifts, and for traction control of front wheel vehicles. This paper outlines a nonlinear dynamic engine model of a port fuel-injected engine, which can be used for control algorithm development. This engine model predicts the mean engine brake torque as a function of the engine controls (i.e., throttle angle, spark advance, fuel flow rate, and exhaust gas recirculation (E. G. R.) flow rate). The model has been experimentally validated for a specific engine, and includes: • intake manifold dynamics, • fuel delivery dynamics, and • process delays inherent in the four-stroke engine. This model is used in real time within a control algorithm, and for system simulation. Also, it is flexible enough to represent a family of spark ignition automotive engines, given some test and/or simulation data for setting parameters.

Currently, advanced control systems implemented on production ground vehicles have the goal of promoting maneuverability and stability. With proper coordination of steering and braking action, these goals may be achieved even when road conditions are severe. This paper considers the effect of steering and wheel torques on the dynamics of vehicular systems. Through the input-output linearization technique, the advantages of four-wheel steering (4WS) system and independent torques control are clear from a mathematical point of view. A sliding mode controller is also designed to modify driver’s steering and braking commands to enhance maneuverability and safety. Simulation results show the maneuverability and safety are improved. Although the controller design is based on a four-wheel steering vehicle, the algorithm can also be applied to vehicles of different configurations with slight changes.

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