Date of Award
Master of Science
Mechanical and Aerospace Engineering
Dr. Kapseong Ro
Dr. Richard Meyer
Dr. Jennifer Hudson
Dr. Peter Gustafson
Innovative Control Effector (ICE), control law synthesis, fly by wire, flight dynamics, fighter aircraft
Masters Thesis-Open Access
This thesis documents a conventional and modern flight control system design process carried out on a tailless aircraft Simulink model with innovative control effectors provided by Lockheed Martin. To set scope and design requirements a performance analysis was carried out to categorize the aircraft. Evaluation of open-loop dynamics reveled modal instabilities as well as state and control coupling. Flight condition dependent pole migration mapping reveled large changes in the aircraft’s static stability. Leading to the development of a four channel proportional-integral- derivative (PID) stability and control augmentation system (SCAS) controlling pitch-rate, roll-rate, side-slip angle, and airspeed states. PID gains are scheduled via iterative constrained optimization throughout the linearized flight envelope generating a full flight envelope flight control system. The linear quadratic (LQ) servo design method provides optimal control allocation at every linearized flight condition, controlling angle of attack, roll angle, side-slip angle, and airspeed states. LQ controlled states were modified to be equivalent to the PID control system for real time handling qualities (HQ) evaluation. Both control systems required gain scaling to prevent state resonance and control saturation during nonlinear 6-degree-of-freedom (6DOF) real-time simulation. Either method achieved stable augmented control of the innovative control effectors (ICE) aircraft throughout the flight envelope. The HQ’s for the control methods are satisfactory for conventional aerobatics but became dissimilar for sustained super-maneuverability flight conditions.
Segard, "Control Law Synthesis for Lockheed Martin’s Innovative Control Effectors Aircraft Concept" (2019). Master's Theses. 4300.