Aircrafts’ control and command using hierarchical dynamic inversion

The paper presents a methodology for the flight control law’s design for the trajectory pursuit using hierarchical dynamic inversion; this is based on separation of multi-time-scale and multi-loop closing method. The attitude angles are taken as slow variable while angular velocities as fast variables. The slow variables are controlled by the fast ones, which, in turn, are controlled by aerodynamic command surfaces. It greatly simplifies the flight control design compared with PID conventional approaches. The used dynamic equations are classified into 4 groups according to the stairs of time measuring from the physical point of view [1]; each group of variables is controlled by the group of faster neighboring variables. The authors made the analysis of the longitudinal and lateral movements of the aircrafts, have obtained two original block diagrams and, using complex Matlab/Simulink models, have obtained graphic characteristics which demonstrate the effectiveness of the proposed method. Key-Words: aircraft, hierarchical dynamic inversion, control law.