Constrained Linear Quadratic Tracker for Optimal Flight Performance

A constrained control technique called the constrained linear quadratic tracker (CLQT) is proposed. The denominated polyhedral flight envelope is constructed from the computed solutions of the nonlinear free-body equations with the advantage of providing achievable speed schedules for maximum performance maneuvers. Aggressive demands of trajectory change were simulated in both calm and turbulent atmospheric conditions. These demands were checked against the real capability of the airframe to attain the required conditions through the polyhedral flight envelope representation. Given the attainable demands, the constrained linear quadratic tracker was capable of maintaining the vehicle within the admissible range of controls and output variables, such as the angle of attack, while tracking the achievable demands without error.