h. behzad

This paper presents a fault tolerant approach for overactuated-oversensed systems subject to multiplicative and additive faults. The main idea is to use a reconciliatory unit in charge to discover online the possibly faulty physical sensors and exclude their measures from the generation of the ”virtual” sensors. In the proposed approach, the energetic based approach has been used to estimate the actuator multiplicative faults. In the next step, an unknown input observer has been coupled with the energetic based estimator to estimate sensor multiplicative and additive faults. Finally, the control allocation approach has been used to reach the desire output. Finally, a simulation example is reported in details to show the effectiveness of the scheme.

In this paper, mechanical buckling analysis of composite annular sector plates with bean shape cut out is studied. Composite material sector plate made of Glass-Epoxy and Graphite-Epoxy with eight layers with same thickness but different fiber angles for each layer. Mechanical loading to form of uniform pressure loading in radial, environmental and biaxial directions is assumed. The method used in this analysis is three dimensional (3D) finite elements based on the elasticity relations. With zero first and second variation of potential energy of the entire annular sector plate, we find stability equation. Green non-linear displacement strain relations to obtain geometric stiffness matrix is ​​used. Unlike many studies, in present work three dimensional finite elements method has been used with an eight node element and meshing in the thickness direction is done, too. The bean shaped cut out in the sector has increased the complexity of the analysis. The continuing, effect of different parameters including cut out dimensions, fiber angles of layers, loading direction and dimensions of the annular sector plate on the mechanical buckling load has been investigated and interesting results have been obtained.