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Modeling techniques matter a lot in many fields of engine engineering. Models are requested not only for control design but also for dynamic prediction. However, problems might be encountered during modeling process either because of the system complexity or the unaffordable modeling cost. As a result, a new modeling technique based on disturbance estimation is proposed in this paper. By employing the proposed modeling technique, models are set up in real time with the online information from input and output. The uncertainties of system dynamics are handled as internal disturbance of the system, while the perturbation from outside are taken as the external disturbance, and the combination of the two can be estimated online by a kind of active observer called extended state observer (ESO).

Aiming at the problem of poor robustness after the combination of lateral kinematics control and lateral dynamics control when an autonomous vehicle decelerates and changes lanes to overtake at a certain distance. This paper proposes a trajectory determination and tracking control method based on a PI-MPC dual algorithm controller. To describe the longitudinal deceleration that satisfies the lateral acceleration limit during a certain distance of lane change, firstly, a fifth-order polynomial and a uniform deceleration motion formula are established to express the lateral and longitudinal displacements, and a model prediction controller (MPC) is used to output the front wheel rotation angle. Through the dynamic formula and the speed proportional-integral (PI) controller to control and adjust the brake pressure.

This paper presents a method to identify the radiation noise source of diesel engine based on a Cepstrum Analysis (CA) and Analytic Hierarchy Process (AHP). Through measuring noise and surface vibrations of a diesel engine, cepstrum analysis is applied to the measured signals. In an investigation of the radiation noise source, the hierarchy tree and judgment matrix are given. Through identification, the main noise source is found. The results show that the left body contributes maximally to non-harmonic spectral characteristics of noise. Therefore, in order to reduce engine vibration and noise effectively, we should optimize and improve left body. In addition, optimizing and improving gear chamber casing, oil pan, inlet pan and valve chamber cover can decrease harmonic vibration and noise of engine.