Determination of parameters during quasi-steady stall maneuver using genetic algorithm

Abstract

The current work offers the determination of longitudinal aerodynamic derivatives during flight manoeuver at angles of attack near the stall. The flight manoeuver near stall is highly non-linear in nature due to separated flow at such elevated angles of attack. Kirchoff's model for Quasi-Steady Stall Modelling (QSSM) is employed to represent the non-linear nature of aerodynamics during flight manoeuver at elevated angles of attack close to the stall. The Genetic Algorithm (GA) optimized output error method is utilized for estimating the parameters specific to stall charactertistics and longitudinal aerodynamics of the ATTAS(Advanced Technologies Testing Aircraft System) aircraft. The comparative evaluation of the parameter estimates with the estimates obtained by using Maximum Likelihood technique is employed to assess the efficacy of the proposed method for highly non-linear applications. The comparative assessment of the estimates along with robust statistical analysis evidence that the proposed method can be a suitable parameter estimation alternative method for non-linear applications.