Hybrid Harris Hawks optimization with eagle strategy particle swarm optimization for stability and disturbance rejection in tethered UAV systems.

In the paper, a new hybrid optimization method is proposed to design an advanced attitude controller of tethered UAVs. The suggested methodology builds on the use of a Fractional-Order Proportional-Derivative-Derivative Integral (FOPDD-I) controller, which is optimized with the help of a Hybrid Harris Hawks Optimization-Eagle Strategy-Particle Swarm Optimization (HHHOESPSO) algorithm. The FOPDD-I controller is compared with Conventional PID, Cascade PID, classical Active Disturbance Rejection Control (ADRC) and Advanced ADRC methodologies. Comprehensive MATLAB simulations indicate that the FOPDD-I controller, optimized through HHHOESPSO, is more stable, responds more quickly to disturbances, and can reject disturbances better than their traditional counterparts. Significant results are a 56.5 percent increase in Kp to achieve better overall stability, a 65.2 percent increase in Ki to achieve smaller steady-state errors and better roll control and a 98.4 percent decrease in Kd to achieve smaller yaw overshoot and oscillations. Also, the fractional-order parameters are adjusted to adaptability improvement of 12.5 and 14.7 in nonlinear dynamic environment. Conversely, traditional controllers including PID and Cascade PID demonstrate only minor tuning benefits, whereas both classical and state-of-the-art ADRC approaches realize moderate performance benefits, that are not as high as the stability and responsiveness demonstrated by FOPDD-I controller. This study underscores the effectiveness of combining fractional-order control with hybrid optimization strategies, establishing the proposed FOPDD-I controller as a robust solution for tethered UAV attitude control under dynamic and uncertain conditions.