## 4 Experimental Evaluation
Furthermore, the SDCS controller achieved a 0% steady-state error (Ess) compared to the 0.003% steady-state error of the PO-FOPID controller, confirming its effectiveness in steady-state response as well. In Figure 14 and Table 8, which show the system output during yaw movement (psi angle), the SDCS controller again provided a lower rise time (Tr) and faster system output than the PO-FOPID controller. The SDCS controller also achieved lower peak time (Tp) and settling time (Ts) values compared to the PO-FOPID controller. The SDCS controller recorded a 0% overshoot (Mp), while the PO-FOPID controller caused a 0.010% overshoot, highlighting the SDCS controller's superiority in transient response. Additionally, the SDCS controller maintained a 0% steady-state error (Ess), while the PO-FOPID controller had a 0.003% steady-state error, reinforcing the SDCS controller's effectiveness in steady-state response as well. Considering Tables 3-8, SDCS showed its superiority over the PO-based FOPID controller. Although the SDCS controller showed a better performance, the FOPID controller provided a close performance to the performance provide by the SDCS controller in control of vertical, roll, pitch, and yaw movements. For some flight control boards, the real-life implementation procedure of the FOPID controller may be simpler and easier than the procedure of the SDCS method. In situations where the SDCS cannot be implementedor is hard to implement, FOPID controllers can be preferred for the real flight control applications of quadcopters [50,51]. Considering the studies in the literature comparing the performance of FOPID and PID methods in quadcopter control, it is seen that most of these controllers are designed with the support of optimization algorithms. This approach has made them near-optimal controllers. When the results obtained with the SDCS method proposed in this paper are compared with the results in recent studies that include the optimal control of the quadcopter, the superiority of the proposed method is better understood. Since speed limits were implemented in the movements of the quadcopter, utilizing time-based criterion such as Tr, Tp, and Ts while comparing the performance of the SDCS method and previous studies is not meaningful. However, Mp and Ess values can be used to evaluate the performances of the controllers. Tables 12 and 13 show the Mp and Ess performances of the compared controllers, respectively. Considering Table 12, which presents the Mp values, the SDCS method shows its superiority over the FOPID controllers proposed in the literature. Considering Table 13, which presents the Ess values, FOPID controllers can provide the same or similar steady-state performances to the performance of the SDCS method. In Figures 9 and 10, the SDCS controller demonstrates several advantages over the FOPID controller in the control of \(X\)-axis movement and \(Y\)-axis movement, respectively. Specifically, the SDCS controller does not introduce dead time, which contributes to a more immediate system response. Additionally, it exhibits a faster transient response compared to the FOPID controller. In terms of steady-state performance, the SDCS controller achieves zero steady-state error, ensuring that the output consistently aligns with the desired value over time. In contrast, the FOPID controller showed dead time, slower transient response, and a non-zero steady-state error. These comparative attributes indicate that the SDCS controller provides superior performance in terms of responsiveness and accuracy for the application under consideration. Figures 9 and 10 prove that the SDCS controller is better than the FOPID controller in the control of the horizontal movements of the quadcopter. Figures 11-14 show the performance of the quadcopter in vertical movement and angular movement. Considering Figures 11-14, the results obtained with the SDCS controller are better, but the performances of the tested controllers are very similar in both transient and steady-state responses.