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MIMO intelligent-PID controller design for half car system based on model free control technique

Djemal Fathi, Haddar Maroua, Baslamisli S. Caglar, Chaari Riadh, Chaari Fakher, Haddar Mohamed

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 4

953--969

EN

A novel decoupled Multi-Input-Multi-Output Model Free Control strategy is presented in this paper to improve the performance of an active suspension system implemented on a half car model. To damp vibrations generated by road excitation, an algebraic online compensator was integrated in the structure of a classical PID controller to avoid the impact of unpredictable disturbances. The key element of the proposed technique is a non-asymptotic observer that can avoid the use of statistical conventional techniques. Furthermore, the advantage of easy implementation is achieved where only two accelerometers are sufficient and adequate. A comparison with classical PID and LQR is provided to demonstrate the improvement made by the proposed scheme.

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The effect of a cracked tooth on the dynamic response of a simple gearbox with a flexible coupling under acyclism operation

Hammami Ahmed, Hmida Atef, Chaari Fakher, Khabou Mohamed Taoufik, Haddar Mohamed

Journal of Theoretical and Applied Mechanics

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2019

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Vol. 57 nr 3

591--603

EN

In this paper, the effect of a cracked tooth on the dynamic response of a simple gearbox with a flexible coupling is studied. The gearbox is driven by a combustion engine through a flexible coupling for which Nelson and Crandall’s model is used. The acyclism regime is generated by diesel engine inducing fluctuations of speed, torque and meshing stiffness. In addition, the cracked tooth of the wheel gear is modelled by lowering the meshing stiffness. After solving the equations of motion by using the Newmark method, the time response, spectrum, joint time-frequency analysis and envelope spectrum are used to characterize the dynamic response of the defected gearbox where the cracked tooth frequency is irregular and independent of the acyclism frequency.

3

Road profile identification using estimation techniques: comparison between independent component analysis and Kalman filter

Chaabane Mariem Miladi, Ben Hassen Dorra, Abbes Mohamed Slim, Baslamisli Selahattin Caglar, Chaari Fakher, Haddar Mohamed

Journal of Theoretical and Applied Mechanics

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2019

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Vol. 57 nr 2

397--409

EN

This paper focuses on the identification of a road profile disturbance acting on vehicles. Vehicles are subjected to many kinds of excitation sources such as road profile irregularities, which constitute a major area of interest when designing suspension systems. Indeed, determining the road profile is important for passive suspension design on the one hand and for determining an appropriate control law for active suspensions on the other. Direct measurement techniques of the road profile are expensive, so solutions based on estimation theory are needed. The aim of this paper is to characterize the road excitation using the Independent Component Analysis (ICA). This proposed method can reconstruct original excitation sources by using physically measurable signals of the system under study. Here, the estimation of road disturbances is considered as output sources and identified from dynamic responses of the vehicle. These responses can be measured via sensors or can be numerically computed. In our case, they are numerically simulated using the Newmark method and consider different types of road profiles. The obtained results are validated after using a comparison with the Kalman filtering. The robustness of the ICA is confirmed via parametric study.