A. KAILILT*, N. M R A N I~, M. MLIHA TOUATI~, S. CHOUKRI~ and N. ELALAMI~ Fractional Order Control methods were applied to a three-axis reaction wheels satellite attitude control system. To show the advantages of this method, a comparative study between a Linear Quadratic Regulator and a Fractional Order Control was established through two principal fractional control laws. The aim is to establish an efJicient control law which satisJies a given speczjication and maintains su-cient stability and accuracy even under the strong efects of intrinsic parameters uncertainties, and also external perturbations.
To ensure the safety and of reducing the costs of maintenances in railways systems, it is necessary to evaluate the life prediction of fatigue crack initiation in rolling contact fatigue starting from the defects. The influence of defects on the rolling contact fatigue was studied, we simulated two types of geometry of defect (circular and elliptic) and also we studied the influence of defects clusters. The stresses and deformations were analyzed in the vicinity of the defect. Calculations were carried out with four levels of loading with the code of finite elements ABAQUS-standard (version 6.3). The fatigue impact was evaluated by using the multiaxial fatigue parameter to estimate the rolling contact fatigue life.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.