Authors:
            
                    Claude Kaddissi
                    
                        
                    
                    ; 
                
                    Jean-Pierre Kenné
                    
                        
                    
                     and
                
                    Maarouf Saad
                    
                        
                    
                    
                
        
        
            Affiliation:
            
                    
                        
                    
                    École de Technologie Supérieure, Canada
                
        
        
        
        
        
             Keyword(s):
            Electro-hydraulic systems modeling, Non-linear control, Backstepping.
        
        
            
                Related
                    Ontology
                    Subjects/Areas/Topics:
                
                        Informatics in Control, Automation and Robotics
                    ; 
                        Robotics and Automation
                    ; 
                        Vehicle Control Applications
                    
            
        
        
            
                Abstract: 
                This paper studies the control of an electro-hydraulic servosystem using a non-linear backstepping based
approach. These systems are known to be highly non-linear due to many factors as leakage, friction and
especially the fluid flow expression through the servo-valve. Another fact, often neglected or avoided, is
that such systems have a non-differentiable mathematical model for bi-directional applications. All these
facets are pointed out in the proposed model of this paper. Therefore, the control of this class of systems should be based on non-linear strategies. Many experiments showed the failure of classic control with electro-hydraulic systems, unless operating in the neighborhood of a desired value or reference signal. The backstepping is used here to overcome all the non-linear effects. The model discontinuity is solved in this paper, by approximating the non-differentiable function by a sigmoid, so that the backstepping could be used without restrictions. In fact, simulation 
                results show the effectiveness of the proposed approach in terms of guaranteed stability and zero tracking error.
                (More)