Summary
This thesis mainly focuses on the robust control of nonlinear flat systems. The main goal is to 
determine a family of robust controllers in order to assure the fulfillment of a desired 
specifications set under parametric uncertainty in the process.
The family of robust controllers are determined with a new approach of robust possibilistic 
control together with the theory of flat systems. The specifications and parametric uncertainty 
are established through the intervals.  Modal Interval Arithmetic and Analysis Quantified Sets 
Inversion Algorithms are applied to find solution sets. Different problems of robust control are 
solved such as: Solution sets referred to the attainable specifications by a family of controllers, as 
well as the determination of the maximum uncertainty admitted by a nominal controller.
This thesis develops a new methodology of robustness analysis of controllers based on 
differential flatness, where the use of a feedforward is required. The methodology developed is 
applied to different processes, especially to fed-batch bioreactors given the importance of these 
high density stirred tank reactors for efficient industrial production of proteins and enzymes.