Simulation Results: Comparing FPID and GSFPID Controllers in Pitch Channel

4.3 Simulation Results

This section presents the simulation results for the FPID and GSFPID controllers implemented in the pitch channel, using a step unit reference signal. The reference signal's initial value is set to 40 (0.698 rad) and reaches a final value of 41 (0.716 rad) within the first second.

Figure 13 displays the Simulink diagram of the nonlinear motion with the GSFPID controller in the pitch channel. Figure 14 depicts the block diagram of the nonlinear dynamic system in the pitch channel, incorporating the GSFPID controller.

To assess the performance of the controllers, we compare the pitch angle outputs of the nonlinear model using both the FPID and GSFPID controllers, as visualized in Figure 15. Figure 16 presents a comparison of the pitch error (the difference between the step unit reference signal and the pitch angle response) between the FPID and GSFPID controllers. Notably, the FPID controller exhibits a significant overshoot at 5.8 seconds, whereas the GSFPID controller does not.

Figure 17 displays the pitch error comparison between the FPID and GSFPID controllers during the boost phase. The GSFPID controller demonstrates no steady-state error. Additionally, Figure 18 illustrates the comparison of the pitch actuator inputs between the FPID and GSFPID controllers. Finally, Figure 19 presents a comparison of the pitch actuator responses during the first second of the boost phase between the FPID and GSFPID controllers.

These simulation results provide valuable insights into the performance and behavior of the FPID and GSFPID controllers in the pitch channel. The GSFPID controller exhibits several advantages, including reduced overshoot, improved tracking, and a more efficient actuator response compared to the FPID controller.