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Unified Control Design for Autonomous Vehicle               311

                                 Equation (8.42) can then be rewritten equivalently as

                                                                    2
                                                               ˙
                                                    ¨ z =¨z d − 2ξλ˜z − λ ˜z           (8.43)
                                 Taking the differentiation of (8.13) yields

                                              ∂(Eµ)
                                          ¨ z =     Gµ + E ˙µ = H(θ, γ)µ + E(θ, γ)u    (8.44)
                                                ∂q
                              where

                                                              T
                                                    H(θ, γ) = R (θ)H(γ )               (8.45)
                                                                  ¯
                              and

                                                                                       
                                                 1 + f             l  v
                                         − tan γ     ˙ θ         −        sin pγ
                                                  2                a cos γ
                                                                      2                
                                                                                       
                                             l
                                                                                       
                                          + ( ˙ θ + pω) cos pγ    −lp( ˙ θ + pω) cos pγ  
                                 ¯
                                H(γ ) =     a                                          
                                                                
                      
                                             l                    1 + f   l          v
                                                                                       
                                        ˙ θ − ( ˙ θ + pω) tan γ sin pγ  +  cos pγ      
                                                                                     2
                                            a                      2     a        cos γ  
                                                                   −lp( ˙ θ + pω) sin pγ
                                                                                       (8.46)
                                 Subsequently, differentiation of (8.31) leads to
                                                1 + f  2
                                                                                     
                                           ˙v −     a ˙ θ             ¨          2      
                                          
                                                                                        
                                      T          2      + fR (φ)    {d − d( ˙ θ + ˙ φ) }
                                                              T
                                                        
                                                 1 + f               ˙
                                ¨ z d = R (θ) 
                                                                  {2d( ˙ θ + ˙ φ) + d( ¨ θ + ¨ φ)} 
                                             v ˙ θ +  a ¨ θ
                                                                                       
                                                   2
                                                                                       (8.47)
                              where
                                                       v tan γ
                                                    ˙ θ =                              (8.48)
                                                         a
                                                       ˙ v tan γ  vω
                                                    ¨ θ =    +                         (8.49)
                                                                    2
                                                         a      a cos γ
                                 Likewise, taking differentiation of ˜z in (8.6) yields
                                                              ˙
                                       T
                                   ˙ ˜ z = R (θ)  −l( ˙ θ + pω) sin pγ − d cos φ + d( ˙ θ + ˙ φ) sin φ  (8.50)
                                             l( ˙ θ + pω) cos pγ − d sin φ − d( ˙ θ + ˙ φ) cos φ
                                                             ˙
                              © 2006 by Taylor & Francis Group, LLC

                                FRANKL: “dk6033_c008” — 2006/3/31 — 16:43 — page 311 — #17
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