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This paper presents a novel model-based algorithm which is able to detect and isolate major faults assigned to the gas exchange path of a gasoline engine both in the intake and exhaust sides. The diagnostics system is developed for detection and isolation of these faults: air leakage fault between the compressor and the air throttle, exhaust manifold pressure sensor fault, wastegate stuck-closed fault and wastegate stuck-open fault. Sliding mode observers (SMOs) are the core detection algorithms utilized in this work. A first order SMO is designed to estimate the turbocharger rotational dynamics. The wastegate displacement dynamics coupled to the exhaust manifold pressure dynamics is estimated using a second order SMO. Verified with experimental data from a modern TC gasoline engine running in a test cell, the two sliding mode observers are then used in a strategy to detect the faults in the gas exchange path.

Proper operation of an internal combustion engine is required by demands of a vehicle driver and governmental legislations. Therefore it is necessary to monitor, within an online technique, the engine and detect any fault which disrupts its normal operation. In this paper, the air-charge path, as a key element in a turbocharged engine, is monitored for an air leakage fault. At first, a robust algorithm to estimate unmeasured turbocharger rotational speed is presented. The sliding mode methodology is used to design the estimator which is shown to be robust to the compressor modeling uncertainties. The estimation error from the sliding mode observer (SMO) is then used to detect abnormal behavior of the turbocharger along with the engine due to a leakage fault in the air-charge path. Experimental results from a modern turbocharged SI engine indicate the designed monitoring technique is able to detect a leakage fault, of 7 mm or higher sizes, in the air-charge path.

One of the main problems associated with design of fault detection (FD) strategy is availability of first generation engine. To solve this problem a methodology based on a virtual engine platform is proposed in this paper. This approach allows designing an FD algorithm in early stages of engine development. The application of this methodology is illustrated on a modern turbocharged gasoline engine by investigating the effect of a leakage in the exhaust manifold. Experimental results show good ability of the virtual engine platform to predict the effect of the leakage fault on the engine performance. Moreover unexpected results of exhaust manifold leakage effects are presented which are very useful for designing a leak detection strategy.

In this article a novel method has been developed to improve the ride comfort of a passenger car by optimum choice of shock absorbers. The objective is to minimize the fatigue provided in the body due to transmitted vibrations. A comprehensive ADAMS model of the car was constructed for perfect simulation of car motions in different maneuvers. This model was validated by further construction of a car and test rig model, and comparing hydro-pulse test data on the real car with simulation results of ADAMS model. The real road profile was adopted as stimulus for the model.

Genetic Algorithm is applied to the physical parameter estimation of a full vehicle nonlinear multi-body ride model. Beforehand unity of system representation (identifiability) and sensitivity analysis for determining the effects of parameter changes on the response of the vehicle is discussed. A random road profile is designed as a persistent excitation. Input-output data required for the identification is obtained from ADAMS/CAR simulations of a more complex model. Robustness of the identification method is studied by adding different noise levels to the ADAMS output signals. Validation of the results is carried out by comparison of the identified model outputs with experimental measurements done on the same vehicle, which its ADAMS model was available. Test was performed on the Schenck hydropuls road simulator. Accuracy of estimated parameters is evaluated by information available from other sources such as technical drawings and performance tests of the vehicle parts.