Page 303 - Control Theory in Biomedical Engineering
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276   Control theory in biomedical engineering


             The stride time transient responses of four control system models are
          plotted in Fig. 5. As shown, stride time of c_TL reached its desired value
          more quickly compared to the others.
             The stride length transient responses of four control system models are
          plotted in Fig. 6. The stride length of c_TL reached its desired value more
          quickly compared to the others. In addition, c_VP did not approach its
          desired value.
             The stride velocity transient responses of four control system models are
          plotted in Fig. 7. Stride velocity c_TLVP reached its desired value less
          quickly than c_TLV.
             The stride position transient responses of four control system models are
          plotted in Fig. 8. Only c_TLVP and c_VP closed to the proper value of the
          position. c_TLVP closed to the desired value much more quickly than c_VP.




            1.15                             1.15

             1.1                             1.1
            Stride time  1.05               Stride time  1.05



              1                               1

            0.95                             0.95
                5  10  15  20  25  30  35  40  45  50  5  10  15  20  25  30  35  40  45  50
           (A)           Stride number     (B)           Stride number


             1.15                            1.3
                                             1.25
              1.1
                                             1.2
             Stride time  1.05              Stride time  1.15
                                             1.1
                                             1.05
               1
                                              1
                                             0.95
             0.95
                 5  10  15  20  25  30  35  40  45  50  5  10  15  20  25  30  35  40  45  50
                                                          Stride number
                         Stride number
           (C)                             (D)
          Fig. 5 Transient responses of stride time (plotted by blue “.” (dark gray “.” in print
          version)) and its desired values (plotted by red “*” (light gray “*” in print version)) are
          shown in (A), (B), (C), and (D) for c_TL, c_TLV, c_TLVP, and c_VP, respectively.
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