Reduced-Order Sliding Mode Observer-Based Backstepping Integral Logarithmic Sliding Mode Control: Application to Wing Aeroelastic System

The suppression of limit cycle oscillations generated by the interplay of structure, inertia, and aerodynamics in a wing aeroelastic system is investigated in this paper. To estimate the plunge rate in wing aeroelastic system, a reduced-order sliding mode observer based on the equivalent control approach is employed. A natural logarithmic function-based integral attractor with a combination of backstepping control and the second-order Sliding Mode Control (SMC) is developed to offer fast transient response and convergence in both scenarios, with and without a bound on the control signal. In the presence of external disturbances, classical SMC, backstepping integral SMC, and logarithmic SMC are employed for comparison to assess the efficacy of the suggested control technique in both cases. The asymptotic global stability of the proposed closed-loop system is guaranteed by the Lyapunov stability theory. Simulation and numerical analysis outcomes show that the suggested control technique outperforms the other three mentioned control approaches in terms of transient response and convergence for the wing aeroelastic system.