Synthesize of Design of Lateral Autopilot

Abstract

Autopilot systems have been until now crucial to flight control for decades and have been making flight easier, safer, and more efficient. This is a report of a project aimed to Synthesize of Design by modeling and simulating a lateral autopilot for Boeing747-E by going through all design steps starting from longitudinal derivatives ends to evaluation using assumptions of equations of motions, MATLAB and control theories. The longitudinal motion has two modes: short mode and Long mode (phugoid), results showed a stability problem at the long period (phugoid), solved by fixing a PD controller. Lateral motion has three modes; rolling, spiral, and Dutch roll. The dynamic response was oscillated during Dutch roll mode. The challenge is to make the passengers comfortable that not to sense the oscillation. Thus to enhance the stability a gain ( ) were added in the feedback loop. Results were presented as a dynamic response in the time domain and analyzed using root locus to evaluate the addition of the controllers on the longitudinal and lateral stability, the location of the poles and zeros on the plan and their effect on the modes was clear and positives.