This note derives an explicit expression for computing the robustness margin for affine systems whose real and complex coefficients are related by an ellipsoidal constraint. The expression, which is an application of a result by Chen, Fan, and Nett for rank-one generalized structured singular-value problems, extends and unifies previous results on robustness margin computation for systems with ...

Biological systems that have been experimentally verified to be robust to significant changes in their environments require mathematical models that are themselves robust. In this context, a necessary condition for model robustness is that the model dynamics should not be sensitive to small variations in the model's parameters. Robustness analysis problems of this type have been extensively stu...

In this contribution the automated generation of LFT-based parametric uncertainty descriptions from a generic nonlinear aircraft-dynamics model, as used for the GARTEUR RCAM Design Challenge on Robust Flight Control, is described. For this purpose an object-oriented, equation-based modeling approach using the modeling environment Dy-mola was applied. Using this technique allows the modeling of ...

Mixed performance control problems have been the object of much attention lately. These problems allow for capturing different performance specifications without resorting to approximi+ tions or the use of weighting functions. However, up to date most of the work concerning multiobjective control is limited to guaranteeing nominal performance and robust stability. In this paper we analyze robus...

A desirable property of control systems is to be robust to inputs, that is small perturbations of the inputs of a system will cause only small perturbations on its outputs. But it is not clear whether this property is maintained at the implementation level, when two close inputs can lead to very different execution paths. The problem becomes particularly crucial when considering finite precisio...

Avionics embedded systems are confronted to sensors errors or inaccuracies. It is essential to be able to estimate the impact and the propagation of these errors on the system computed outputs. This paper comes from achieved work in the context of an industrial project in the avionics area. It presents a formal approach allowing to analyse the reaction of a LUSTRE program to inaccurate input va...

This paper presents two approaches to robustness analysis in multi-objective optimization problems, in which the model data (coefficients of objective functions, coefficients of constraints, bounds of decision variables, etc.) are subject to small perturbations, with respect to a ”nominal” set of coefficients of the model data. In these approaches, the concept of degree of robustness is incorpo...

We propose a symbolic algorithm for the analysis of the robustness of timed automata, that is the correctness of the model in presence of small drifts on the clocks or imprecision in testing guards. This problem is known to be decidable with an algorithm based on detecting strongly connected components on the region graph, which, for complexity reasons, is not effective in practice. Our symboli...

l We like to thank Sjoerd Beugelsdijk and Ton van Schaik for testing the program and providing useful suggestions. Henri de Groot acknowledges financial support fiom the Netherlands Organisation for Scientifïc Research (NWO).