The present thesis employs ideas of set invariance and sliding modes

in order to deal with different relevant problems control of nonlinear

systems. Initially, it reviews the techniques of set invariance as well as

the more relevant results about sliding modes control. Then the main

methodologies used are presented: sliding mode reference conditioning,

second order sliding modes and continuous approximation of sliding

modes. Finally, the methodologies are applied to different problems in

control theory and to a variety of biologically inspired applications.

The contributions of the thesis are:

The development of a method to coordinate dynamical systems

with different dynamic properties by means of a sliding mode auxiliary

loop shaping the references given to the systems as function

of the local and global goals, the achievable performance of each

system and the available information of each system.

Design methods for second order sliding mode algorithms. The

methods decouple the problem of stability analysis from that of

finite-time convergence of the super-twisting sliding mode algorithm.

A nonlinear change of coordinates and a time-scaling are

used to provide simple, yet flexible design methods and stability

proofs. Application of the method to the design of finite-time convergence

estimators of bioprocess kinetic rates and specific biomass

growth rate, from biomass measurements. Also the estimators are

validated with experimental data.

The proposal of a strategy to reduce the variability of a cell-to-cell

communication signal in synthetic genetic circuits. The method

uses set invariance and sliding mode ideas applied to gene expression

networks to obtain a reduction in the variance of the communication signal.

Experimental approaches available to modify the

characteristics of the gene regulation function are described.

Among the possible meanings of the word, this paper will discuss coordinated action to refer to the act on

references of systems to achieve some collective behavior

desired but considering the constraints and capabilities of each system.

To this end, we develop a new methodology based on conditioning techniques

reference using geometric invariance sets and sliding mode control.

From a general framework, we propose two approaches:

a global centralized one and a local through interactions between different systems.

The approach addresses the problem

of coordinating dynamical systems with possibly different dynamics

(e.g. linear and nonlinear, different orders, constraints,

etc.).The main idea is to shape the systems local feasible references

in order to keep them coordinated.To show the applicability of the approach, the problem

of coordinating different dynamical systems with

control saturations is addressed as a particular case with both global and local configuration.

%B Revista Iberoamericana de Automática e Informática industrial
%V 10
%P 390-401
%G eng
%N 4
%& 390
%0 Journal Article
%J Control Engineering Practice
%D 2013
%T Second-Order Sliding Mode Observer for Multiple Kinetic Rates Estimation in Bioprocesses
%A S. Nuñez
%A Hernán De Battista
%A F Garelli
%A A Vignoni
%A J Picó
%X Specific kinetic rates are key variables regarding metabolic activity in bioprocesses. They are non-linear functions of concentrations and operating conditions and therefore of difficult access for process control. In this paper, a multiple kinetic rates observer based on second-order sliding mode ideas is proposed. The main difference with other proposals is that smooth estimates are achieved in finite-time without adding additional dynamics. The resulting estimator is robust against uncertainty in the model of the estimated variables. Experimental results from continuous fermentation of *S. cerevisiae* are presented, where microbial specific growth rate and net ethanol production rate are estimated.

A novel approach is proposed for coordination of swarms of dynamical systems in order to provide them with a desired collective behavior. The approach is based on the sliding mode reference conditioning technique as local interaction handler among neighbor systems. Neighbor systems become connected when a virtual constraint between them is violated, leading to a time-varying switching topology for the connections in the swarm. The approach addresses the problem of coordinating dynamical systems with possibly different dynamics (e.g. linear and nonlinear, different orders, constraints, etc.), assuming there is no leader. The main idea is to shape the systems local feasible references in order to keep them coordinated. Coordination is understood as invariance of a set defined by some aimed relationship among the references. This implies considering the local goals, the systems constraints and the achievable performances as well. To show the applicability of the approach, the problem of coordinating a swarm of different dynamical systems with control saturations is addressed as a particular case.

%B Variable Structure Systems (VSS), 2012 12th International Workshop on %I IEEE %C Mumbai, Maharashtra %8 2012/01/12 %@ 978-1-4577-2065-9 %G eng %M 12616630 %R 10.1109/VSS.2012.6163507 %0 Thesis %D 2011 %T Coordination in dynamical systems: a sliding mode reference conditioning approach %A A Vignoni %I Universitat Politècnica de València %C http://personales.upv.es/alvig2/MT/vignoni-mthesis.pdf %G eng %9 masters %0 Conference Paper %B 18th IFAC World Congress %D 2011 %T Dynamical Systems Coordination Via Sliding Mode Reference Conditioning %A A Vignoni %A J Picó %A F Garelli %A Hernán De Battista %E Sergio, Bittanti, %K Control of constrained systems %K Control of switched systems %K Coordination %K Switching stability and control %XA novel methodology is proposed for coordination of dynamical systems. The scheme is based on the sliding mode reference conditioning technique in a sort of supervisory level. The approach addresses the problem of coordinating dynamical systems with possible different dynamics (eg linear and nonlinear, different orders, constraints, etc). To achieve this, the dynamics of each subsystem are emph{hidden} from the coordination mechanism. The main idea is to shape the systems local references in order to keep them coordinated. This implies considering the global goals, the systems constraints and the achievable performances as well. Sliding Mode Reference Conditioning (SMRC) is used for this purpose by means of a hierarchical supervisory structure. To show the applicability of the approach, the problem of coordinating a number of different dynamical systems with control saturations is addressed as a particular case. Coordination will be understood as actuating on the systems references to achieve some emph{collective behavior} considering the individual restrictions of each system.

%B 18th IFAC World Congress %I IFAC %C Università Cattolica del Sacro Cuore, Milano, Italy %8 08/2011 %@ 978-3-902661-93-7 %G eng %U http://www.ifac-papersonline.net/Detailed/51115.html %R 10.3182/20110828-6-IT-1002.02727 %0 Journal Article %J Journal of Process Control %D 2011 %T Specific growth rate estimation in (fed-)batch bioreactors using second-order sliding observers %A Hernán De Battista %A J Picó %A F Garelli %A A Vignoni %B Journal of Process Control %V 21 %P 1049–1055 %G eng %0 Journal Article %J LINAC08, this proceedings, Victoria, British Columbia, Canada %D 2008 %T Optimizing cavity gradients in pulsed Linacs using the cavity transient response %A Cancelo, G. %A A Vignoni %B LINAC08, this proceedings, Victoria, British Columbia, Canada %G eng %0 Generic %D 2008 %T Real Time RF Simulator (RTS) and control %A Cancelo, G. %A Armiento, C. %A Treptow, K. %A A Vignoni %A Zmuda, T. %G eng