Page 363 - Modern Control Systems
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Section 5.7  Performance  Indices                                   337
                           1.2






                        &  0.8
















                                                 Normalized  time
       FIGURE 5.30                                   (c)
       [Continued)
                        The standard form for a third-order system given in Table 5.6 requires that
                                                                                _
                                                                                  ,.3
                                                                             .2
                                  2£&>o =  1.75w„,  0)1  =  2.15(0%  ,  and  K aK„,o)Q 0)„
                           Examining Figure 5.30(c) for n  =  3, we estimate that the settling time is approxi-
                        mately 8 seconds (normalized time). Therefore, we  estimate that
                                                        a) nT s  = 8.
                        Because a rapid response  is required, a large o)„ will be selected  so that the settling
                        time  will be  less than  1 second. Thus, o)„  will be  set  equal  to  10 rad/s. Then, for  an
                        ITAE system, it is necessary that the parameters of the camera dynamics be
                                                    (o 0 =  14.67 rad/s
                        and
                                                       C =  0.597.
                        The amplifier  and motor gain are required  to be

                                                                  (t>, t
                                            K  K  = - 3  =            =  4.65.
                                                    0)1  2X50)1  2.15
                        Then the closed-loop transfer  function  is
                                                 1000
                                 T(s)  =  3
                                        s  +  17.5 J  + 2155 + 1000
                                                 2
                                                           1000
                                                                                           (5.49)
                                        (s  + 7.08)(5 + 5.21 + /10.68)(5 + 5.21 - /10.68)
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