Abstract
This thesis presents the design of automatic control systems to improve dynamic stability and provide pilot relief in aircraft. The study focuses on the longitudinal and lateral dynamics of a Boeing 747, employing classical and modern control techniques such as root locus, state-space, linear quadratic regulator, and pole placement methods. Transfer functions for the longitudinal and lateral directions were derived from the linearized equations of motion. Root locus analysis was performed using the characteristic equations of these transfer functions to find the aircraft motion modes with provided aircraft data. State-space models were constructed from the linearized equations of motion for longitudinal and lateral directions. Linear quadratic regulator and pole placement methods were employed to construct feedback control designs in state-space to model the aircraft response to a control surface input. The systems are modeled in MATLAB and validated using Simulink.
This work demonstrates the effectiveness of state-space models in simulating directional motion responses to internal and external disturbances. It further shows that the Linear Quadratic
Regulator and Pole Placement methods remain robust solutions for automatic flight control systems.