Forming limit curves are used as a parameter in finite element analysis to control the material's level of formability. In this research, forming limit diagram (FLD) of SS304L sheet was obtained by ABAQUSfinite element software. In practice, the experimental determination of a forming limit curve is a very time-consuming procedure which requires special and expensive equipment. Forming limit di...

A necessary and sufficient criterion to establish input-to-state stability (ISS) of nonlinear dynamical systems, the dynamics of which are periodic with respect to certain state variables and which possess multiple invariant solutions (equilibria, limit cycles, etc.), is provided. Unlike standard Lyapunov approaches, the condition is relaxed and formulated via a sign-indefinite function with si...

In this paper we address the problem of generating asymptotically stable limit cycles for a fully actuated multibody mechanical system through a feedback control law. Using the concept of conditional stability the limit cycle can be designed for a lower dimensional dynamical system describing how the original one evolves on a chosen submanifold and the corresponding velocity space. Moreover, th...

Control theory has significantly evolved in the field of the nonlinear control. However, the methods used in the aerospace industry lie usually on linear techniques applied to linearized models. The increasing requirements in terms of operational reliability and performance ask for the development of new control techniques more complex in order to meet the new demands. Therefore the industry is...

The wing rock phenomenon is a high angle of attack aerodynamic motion manifested by limit cycle roll oscillations. Experimental studies reveal that direct control and manipulation of leading edge vortices, through the use of ‘blowing’ techniques is effective in the suppression of wing rock. This paper presents the design of a robust controller for the experimental implementation of one such ‘bl...

In this paper, we introduce some analysis tools for switched and hybrid systems. We first present work on stability analysis. We introduce multiple Lyapunov functions as a tool for analyzing Lyapunov stability and use iterated function systems (IFS) theory as a tool for Lagrange stability. We also discuss the case where the switched systems are indexed by an arbitrary compact set. Finally, we e...