On–off and proportional–integral controller for a morphing wing. Part 2: Control validation – numerical simulations and experimental tests

The second part of this article describes the numerical simulation and experimental validations of actuators control system for a morphing wing application, which was developed and designed in the first part of this article. After the description of the finally adopted control architecture, the validation for the non-linear system model is presented. First, the integrated controller is validated numerically with MATLAB/Simulink software, followed by a physical implementation of the control and experimental validation in the wind tunnel. To implement the controller on the physical model, two programmable switching power supplies, AMREL SPS100-33, and Quanser Q8 data acquisition card were used. The inputs of the data acquisition card were the two signals issued by the linear variable differential transformer potentiometers, indicating the positions of the actuators, and the six signals recorded by thermocouples installed on the SMA wires. The acquisition board output channels were used to control the required power supply to obtain the desired skin deflections. The control experimental validation was performed first on a bench test and then in the wind tunnel test. A number of optimized airfoil shapes, used in the design phase, were translated into actuators vertical displacements which were used as input signals for the controller. In the wind tunnel tests, a comparative study was realized around the transition point position for the reference airfoil and for each optimized airfoil.