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Adaptive Neural-Fuzzy Control of Mobile Robots             237

                              Let T 1 (q) : q → X as


                                                x 1 = h 1
                                                x 2 = L n−2  h 2
                                                      r 1
                                                   .
                                                   .
                                                   .
                                                       h
                                              x n−1 = L r 1 2
                                                x n = h 2

                              It may be verified that T 1 (q) is a valid change of coordinates by evaluating the
                              Jacobian of T 1 (q) at the origin.
                                        L n−2 h 2  = 0, let T 2 (q) : ˙z → u as
                                 Since L r 2 r 1

                                               ˙ z 1 := u 1
                                                       1           n−1
                                               ˙ z 2 :=  n−2  [u 2 − (L  h 2 )u 1 ]
                                                      L            r 1
                                                   L r 2 r 1  h 2
                              Then, the local coordinate transformation X = T 1 (q) and state feedback
                              ˙ z = T 2 (q)u render system (6.12) into the chained form

                                                        ˙ x 1 = u 1
                                                        ˙ x 2 = u 2
                                                        ˙ x 3 = x 2 u 1
                                                           .
                                                           .
                                                           .
                                                        ˙ x n = x n−1 u 1

                              Remark 6.1 Under certain conditions which has been stated in
                              Proposition 6.1, the kinematic model (6.5) can be converted into a chained
                              form driven by integrators.


                              6.3 MULTI-LAYER NF SYSTEMS
                              Despite the differences between the NNs and fuzzy logic systems, they actually
                              can be unified at the level of the universal function approximator, which are
                              multilayer feedforward networks that integrate the TSK-type fuzzy system and
                              RBF NN into a connectionist structure.
                                 Typically, fuzzy logic systems are rule-based systems, which consists of the
                              fuzzifier, the fuzzy rule base, the fuzzy inference engine, and the defuzzifier.




                              © 2006 by Taylor & Francis Group, LLC



                                 FRANKL: “dk6033_c006” — 2006/3/31 — 16:42 — page 237 — #9
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