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Chen et al. Complex Eng Syst 2023;3:8  I http://dx.doi.org/10.20517/ces.2022.50   Page 9 of 15





                                            (  ) =       (  )  (  ) +         (  ) +       (  )Δ  (  )  (21)


                                   
                                    
                                    
                               2
                             Õ      
                                                      ×       
                                                  
                                                  
                               =1                      ×      
               where       (  ) =   . .   ,       =   . .    ,
                                .             .   
                                                  
                              Õ                   
                                   
                                                      ×             ×1
                                     
                                    
                               =1   
                                      (  )
                                        0       0   · · ·      0       
                                                                       
                         2
                        Õ                                              
                               −1                                      
                                                0   · · ·      0       
                                                                       
                         =1                                            
                            .           .        .  .          .       
                            . .         . .      . .  .  .     . .     
                                                                       
                                         −1                            
                     (  ) =   Õ    −1  Õ    −1                         
                                                 · · ·  · · ·          
                                                                       
                          =1          =1                               
                            .           .        .  .          .       
                            .           .        .   .  .      .       
                            .           .        .             .       
                                                                       
                                          −1                    −      +1
                       Õ            Õ                     Õ            
                                 −1            −1                     −1  
                                                · · ·  · · ·           
                                                                       
                         =1           =1                    =1          (  )
               To track the reference vehicle model as well as possible, a 3-DOF vehicle model is designed as the reference
               model. According to Eq. (4), the reference discrete output vector can be obtained as follows:
                                               (  ) =       (  )      (   − 1) +       (  )      (   − 1)  (22)
                                                                                                  
               where       (  ) =       ,       (  )            (  )            (  )  ,        (  ) =       ,        (  )             (  )             (  )  ,
                     =         (1/  , 1/  , 1/  ),       (  ) =    −          , and       (  ) =         . The      -step predictive output vector of the
               reference system can be expressed as follows:



                                                                                          
                                   (  ) =        (   + 1)        (   + 2)  · · ·        (   +       )  · · ·        (   +       )  (23)


               Accordingly, the output vector of each future predictive       steps of the reference system is given as follows:




                                                    (  ) =               (  ) +               (  )     (24)


                                                           "                              #   
                                                                  2                   
                                                                 Õ      −1      Õ      −1
               where         =            2     · · ·        , and         =                    · · ·             . In addition, the
                                                                   −1             −1
               following relationship       (   + 1/  ) =       (  )(   = 1, 2 · · ·       ) holds.
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