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Recent metaheuristics on control parameter determination
                                          Table 8. Statistical results of the methods

                                 No Methods Min         Mean         Max.        Std
                                 1   CO         3.8723  75.7473      341.1709    148.4326
                                 2   PO         3.5314  4.1219       5.0070      0.7211
                                 3   AO         3.5161  4.6367       6.6439      1.3972
                                 4   GOA        3.4950  3.5158       3.5716      0.0317
                                 5   POA        3.4790  3.8902       4.9990      0.6589
                                 6   GJO        3.4839  3.5038       3.5383      0.0222
                                 7   FDA        3.4913  3.5625       3.6115      0.0518
                                 8   EO         3.4775  3.5065       3.5461      0.0319
                                 9   ARO        3.5161  4.6367       6.6439      1.3972
                                 10  CSA        3.9982  73.3512      339.1747    148.6448
                                 11  WOA        3.5171  6.8791e+218 3.4395e+219 Inf
                                 12  GWO        3.4833  4.4826       6.8118      1.4526
                                 13  FPA        3.6329  71.7655      338.1445    148.9295
                                 14  CMAES      63.4304 317.4418     383.8003    142.0176

            CSA. Computational times for all methods are      been used in this field, and an effective con-
            presented in Figure 7. In terms of the computa-   trol design for a two-wheeled self-balancing vehi-
            tional times, CO method converged to the optimal  cle. The optimal controller designed with con-
            solution in the shortest time. EO, GWO, FPA,      sidered metaheuristics, which are Flow Direc-
            ARO, and CMA-ES also converge to the optimal      tional, Cheetah Algorithm and Politican, Equi-
            point shorter time than other algorithms. The     librium, Aquila, Artificial Rabbit, Golden Jackal,
            GWO method is found the optimal point in the      Gazelle, and Pelican Optimizers, are implemented
            longest time.                                     to the two-wheeled vehicle.   The balance and
            The statistical results of all algorithms are pre-  speed controller of the vehicle are performed with
            sented in Table 8.   The minimum, maximum,        PI controllers. For this purpose, the cascade PI
            mean, and standard deviations are included in     controller parameters are tuned with the meta-
            this table. The results for all algorithms are ob-  heuristic methods. Since conventional PID tun-
            tained with 5-runs.                               ing methods need more flexibility and robustness,
            In Table 8, PO, AO, GOA, POA, GJO, FDA, EO,       metaheuristic methods-based tuning approaches
            ARO, CSA, GWO, and FPA methods produce            are seen as crucial importance in solving com-
                                                                                       16, 38-40
            similar results in terms of mean values, whereas  plex engineering problems.      The efficiencies
            the CO, WOA, and CMA-ES methods have the          of the optimization-based tuning algorithms are
            worst values. The GJO method is seen as the       assessed, comparatively. The statistical results,
            best algorithm, and EO, GOA, and FDA follow       convergence curves, dynamic system character-
            the GJO method in terms of the mean values. Ac-   istics, and computation times are evaluated by
            cording to the minimum values of the algorithms,  performing all methods under equal conditions.
            the EO, POA, GWO, and GJO algorithms pro-         In the qualitative and quantitative analysis, it is
            duced the best results, respectively. Since the   observed that 11 out of 14 compared algorithms,
            methods take a long time to run in such systems,  namely PO, AO, GOA, POA, GJO, FDA, EO,
                                                              ARO, CSA, GWO, and FPA methods, produced
            it is important to reach the most optimal solution
                                                              similar optimal results in the speed and balance
            in a short time when solving such problems.
                                                              control of the two-wheeled vehicle. However, it
            When examining the theoretical aspects of algo-
                                                              is observed that CMA-ES, WOA, and CO meth-
            rithms, it is clear that while the applications and
                                                              ods do not give satisfactory results for tuning the
            common control parameters of metaheuristic al-
                                                              optimal control parameters.
            gorithms are similar, the convergence behaviors
            in finding the optimal solution change due to the  The control parameter determination with meta-
            differences in the strategies used in the movement  heuristics approaches is one of the best ways be-
            updates of the agents. This provides an overview
                                                              cause they offer more efficient solution with their
            of the effectiveness of the strategies employed in
                                                              simple structures compared with the traditional
            the methods.
                                                              methods. In addition, this problem is quite ap-
                                                              propriate for demonstrating the success of the
            5. Conclusion
                                                              metaheuristic algorithms. This study will pro-
            This study presents a comprehensive analysis of   vide insights for researchers using metaheuristic
            current metaheuristics, most of which have never  methods in this field for where to start and which
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