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Verification and validation (V&V) are essential stages in the design cycle of industrial controllers to remove the gap between the designed and implemented controller. In this study, a model-based adaptive methodology is proposed to enable easily verifiable controller design based on the formulation of a sliding mode controller (SMC). The proposed adaptive SMC improves the controller robustness against major implementation imprecisions including sampling and quantization. The application of the proposed technique is demonstrated on the engine cold start emission control problem in a mid-size passenger car. The cold start controller is first designed in a single-input single-output (SISO) structure with three separate sliding surfaces, and then is redesigned based on a multiinput multi-output (MIMO) SMC design technique using nonlinear balanced realization.

This paper treats the problem of estimating the longitudinal velocity of a braking vehicle using measurements from an accelerometer and wheel speed data from standard antilock braking wheel speed sensors. We develop and experimentally test three velocity estimation algorithms of increasing complexity. The algorithm that works the best gives peak errors of less than 3 percent even when the accelerometer signal is significantly biased.

A novel design for hydraulic actuation of the valves of internal combustion engines is presented. The main purpose of this design is to enable computer control of the engine valves opening and closing timing. The outstanding characteristics of the system are its simplicity and expected energy efficiency. The dynamic behavior and the synchronization accuracy are analyzed with the help of computer simulations. The results indicate that the proposed design is a feasible way of achieving computer-controlled synchronization of the timing of internal combustion engine valves. The synchronization accuracy and energy consumption obtained are comparable to conventional mechanical systems.

Simultaneous control of speed and air-fuel ratio in a six-cylinder automobile engine is studied. A three-state engine model including rotational, air intake and fuel intake dynamics is used for control design. Control design focuses on application of nonlinear control techniques, specifically sliding mode control. Controllers are designed for tracking speed profiles and regulating air-fuel mixture. Multiple-surface sliding control is shown to result in good speed tracking in simulation and experiment. The production fuel controller and an observer-based sliding controller are shown to result in the best fuel control during speed transients. A standard sliding fuel controller is shown to result in high amplitude deviations due to oxygen sensor time delay. The best combination of controllers is shown to be the multiple-surface sliding speed controller and the observer-based fuel controller.