Identification of aileron control derivatives based on measured loads in maneuvering flight

Abstract

When a certain type of aircraft is maneuvered laterally, the aileron and the spoiler will be coupled and deflected to realize the rolling motion of the aircraft. The existing aerodynamic parameter identification methods cannot separately identify the control derivatives of the aileron and the spoiler. Based on the design logic of the aircraft control law and the loading characteristics of the structure during the roll motion, a new method for identifying the aileron control derivative based on the flight measured load is proposed. Firstly, the measurement method of wing aerodynamic load in maneuvering flight is proposed by measuring the structural loads of each load-testing section of the wing in maneuvering flight and combining the structural mass and acceleration distribution outside the section. Secondly, combining the instantaneous rolling moment balance of aircraft lateral control based on the equation and control surface deflection logic, the identification process of aileron control derivatives during roll recovery is deduced, and the identification method of aileron control derivatives based on the measured load of the wing is proposed. Finally, based on the aforementioned method, the identification of aileron control derivatives is carried out, and the influence of different Mach numbers on the derivative of aileron control is analyzed. The results show that the aileron control derivative can be identified based on the flight measured load, and the concentration of the aileron control derivative results is better at the same Mach number. As the Mach number increases, the aileron control effectiveness will decrease. The measured results of flight loads have the potential to be applied to the identification of aerodynamic parameters.

Keywords

• flight measured load
• aerodynamic load
• aileron control derivative
• parameter identification