Page 93 - IJOCTA-15-2
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                          M. Yavuz, M. Ozt¨urk, B. Ya¸skıran / IJOCTA, Vol.15, No.2, pp.281-293 (2025)
























































                                Figure 7. Θ 2 control signals under SMC and FOSMC controllers

            Table 2. Mean RMSE values under SMC and FOSMC controllers

                              Derivative (α)  SMC     Approach 1 Approach 2 Approach 3
                                              0.1553
                                 α = 0.1                0.1537       0.5040       0.1494
                                 α = 0.5                0.1357       0.3089       0.1332
                                 α = 0.9                0.1160       0.1894       0.1151


            for α = 0.1 because only the difference in the er-  seen in Figures 6, 7, the SMC, approach 1, and
            ror parameter affects the difference in the results.  approach 3 have similar control signal reactions.
            As α value increases, the difference in results also  No control signal limits were used in this study to
            gets bigger. When the error Figures (4, 5) are ex-  ensure a fair comparison. Three of the controllers
            amined, it is seen that approach 3 and SMC error  (SMC, approach 1, approach 3) react quickly in
            values are close. As the α value increases, the dif-  the first seconds. This situation occurs due to
            ferences in errors will also get bigger and RMSE  initial conditions those were [ , ], respectively.
                                                                                           π π
                                                                                           4  2
            values decrease concerning the derivative effect.  Only, approach 2 does not fast control signal re-
                                                              action as seen in Figures (6, 7). Moreover, the
                The control signals are examined for [0 0.5]  RMSE value of approach 2 is larger than the oth-
            seconds because the control signals of all control  ers and the system oscillates at most of the α
            structures continue regularly after 0.5 seconds. As  values.
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