Michel Joël Tchatchueng Kammegne

DESIGN AND VALIDATION OF A POSITION CONTROLLER IN THE PRICE-PAÏDOUSSIS WIND TUNNEL

Conventional or brushed DC motors are often used for many industrial applications. A large variety of these motors is found in automation, medical, robotics and aeronautical fields. In this paper, the design and experimental validation of a position controller for a morphing wing design application is presented. Matlab/Simulink was used to design the Proportional Integral Derivative controller. For experimental validation, tests were carried out in the Price-Paidoussis subsonic blow down wind tunnel. The upper wing surface was deformed by means of a mechanical system consisting of two eccentric shafts. Both are connected to electrical actuators. Comparisons of two sets of results are provided in this paper. The first set is related to control validation and the second set is related to aerodynamic validation.

Design and wind tunnel experimental validation of a controlled new rotary actuation system for a morphing wing application

The paper presents the design and the experimental validation of a position controller for a morphing wing application. The actuation mechanism uses two DC motors to rotate two eccentric shafts which morph a flexible skin along two parallel actuation lines. In this way, the developed controller aim is to control the shape of a wing airfoil under different flow conditions. In order to control the actuators positions, a proportional–derivative control algorithm is used. The morphing wing system description, its actuation system structure, the control design, and its validation are highlighted in this paper. The results, obtained both by numerical simulation and experimental validation, are obtained following the control design and its validation. An analysis of the wind flow characteristics is included as a supplementary validation; the pressure coefficients obtained through numerical simulation for several desired airfoil shapes are compared with those obtained through measurements for the experimentally obtained airfoil shapes under different flow conditions.

Control validation of a morphing wing in an open loop architecture

Aircraft wings are generally designed and optimized to give the best possible performance for cruise flight conditions. Using conventional control surfaces such as flaps, ailerons, variable wing sweep and spoilers, the structure of aircraft wings is changed for other flight conditions. With the introduction of wing morphing, the flow over an aircraft’s wings can be modified locally to improve the overall wing and aircraft performance during the different flight steps. The goal of this research work is to develop an actuation control principle using a grid consisting of four similar miniature electromechanical actuators for a new morphing wing mechanism. The actuators modify the flexible upper surface of the wing so that the upper flow is modified and consequently the transition point from laminar to turbulence is delayed. The flexible upper wing surface is closed to the wing tip, while the skin is made of composite materials. The first actuation line is located at 32% and the second actuation line is at 48% of the chord. The actuators are fixed on the wing ribs and the top is attached to the flexible skin with screws. A database that relates the actuator displacements and the optimized skin is tailored for different flight conditions. A smart controller based fuzzy logic is designed to control the position of the actuator in real time so that the desired optimized skin corresponding to the desired displacements is obtained and maintained during the flight tests. The feasibility and the effectiveness of the control method are demonstrated experimentally.

Nonlinear control logic for an actuator to morph a wing: Design and experimental validation

This paper describes the design of a double loop fuzzy logic position and torque controller for wing morphing using brushed DC motors as actuators. The DC motor is used in this application as an actuator to change the shape of a wing upper surface. To morph the wing with these actuators, a mechanical system coupled to the actuators is integrated in the wing. The fuzzy logic technique is used to design two controllers: one for the position and the other for the torque, to control the position and the torque of the each actuator. The controllers are validated numerically with Matlab/Simulink software, followed by a physical implementation of the control and experimental validation setup in the PRICE-PAIDOUSSIS wind tunnel. The physical implementation is realized using a programmable power supply, the CPX400. The actuators are connected to the output of the power supply and the output of the torque controller, which is the command signal (voltage), is sent to the input of the programmable power supply. In addition to the design of the fuzzy controllers (position and current controller), their performance is compared to that of a Proportional Integral Derivative controller designed and experimentally tested in a previous approach.

New methodology for the controller of an electrical actuator for morphing a wing

The modeling, simulation and control of an electrical actuator used for morphing wing are presented. Because of its small size, this actuator belongs to the category of miniature actuators. Before proceeding with the modeling, the actuator was tested experimentally to ensure that the entire range of the requirements (rated or nominal torque, nominal current, nominal speed, static force, size) would be fulfilled. The complete electromechanical energy miniature actuator was designed in-house, as there is no actuator on the market that could fit directly inside the wing model. The wing model is a portion of an existing regional aircraft. The miniature electrical actuator consists of a brushless direct current (BLDC) motor with a gearbox and a screw for pushing and pulling the flexible upper surface of the wing. The electrical motor and the screw are coupled through a gearing system. The first part of the paper gives a literature review of the actuators used for morphing wing. The theoretical analysis of the BLDC motor and its gearbox are presented in the second part. The design of both controllers (a current and a positioning controller) used to improve the dynamic behavior of the actuator are presented in the third part. The experimental results of the numerical analysis will be presented in a subsequent paper. The numerical analysis is done with MATLAB/SIMULINK, and a Digital Signal Processor (DSP) will be used for experimental evaluation.

New control methodology for a morphing wing demonstrator

A morphing wing can improve the aircraft aerodynamic performance by changing the wing airfoil depending on the flight conditions. In this paper, a new control methodology is presented for a morphing wing demonstrator tested in a subsonic wind tunnel in the open-loop configuration. Actuators integrated inside the wing are used to modify the flexible structure, which is an integral part of the wing. In this project, the actuators are made in-house and controlled with logic control, which is developed within the main frame of this work. The characterization of the flow (laminar or turbulent) over the wing is obtained starting from the pressure signals measured over the flexible part of the wing (upper surface). The signals are acquired by using some pressure sensors (Kulite sensors) incorporated in this flexible part of the wing upper surface. The technique used to collect Kulite pressure data and the post-processing methodology are explained. The recorded pressure data are sometimes subjected to noise, which is filtered before being processed. The standard deviation and power spectrum visualization of the pressure data approaches are used to evaluate the quality of the flow over the wing and estimate the transition point position in the area monitored by the Kulite sensors. In addition, infrared thermography visualization is implemented to observe the transition region over the entire wing upper surface, and to validate the methodology applied to the pressure data in this way. The demonstrator measures 1.5 m chordwise and 1.5 m spanwise. Four miniature actuators fixed on two actuation lines are used to morph the wing. The wing is also equipped with a rigid aileron. The experimental aerodynamic results obtained after post processing validate the numerical prediction for the transition location.