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-Païdoussis 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.

No abstract

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.

The technique of morphing takes its origin from the bird flight and allows an airplane to change its original configuration during flight depending on the flight conditions. The main objective of the morphing is to improve the mission performance in order to optimize and control the fuel consumption efficiency. The experimental results of a morphing wing concept are presented on a part of the upper surface of the wing which is flexible. The wing was equipped with an aileron which was considered as a separated wing's entity. The objective was to reduce the drag by delaying or by moving the transition point towards the trailing edge. Another project objective was to compare the aerodynamics effects of the rigid aileron with the aerodynamic effects of the morphing aileron. The shape of the wing upper surface was modified by a set of four miniature electrical actuators inserted directly inside the wing. The positions of the actuators were controlled by four different controllers. These controllers have been designed based on the actuators simulation models. Three sets of wind tunnel tests have been performed with the manufactured demonstrator. Experimental resultsrevealed a promising controller behavior. The visualization of the flow over the wing upper surface was done with the infrared measurement technique. Using the same technique, the transition region location was estimated and compared with transition location determined by the pressure sensors array installed in the wing upper surface. Nomenclature M = Mach number α = Angle of attack β = Deflection angle CRIAQ = Consortium for Research and Innovation in Aerospace in Quebec LVDT = Linear Variable Differential Transducer

The paper focuses on the modelling, simulation and control of an electrical miniature actuator integrated in the actuation mechanism of a new morphing wing application. The morphed wing is a portion of an existing regional aircraft wing, its interior consisting of spars, stringers, and ribs, and having a structural rigidity similar to the rigidity of a real aircraft. The upper surface of the wing is a flexible skin, made of composite materials, and optimised in order to fulfill the morphing wing project requirements. In addition, a controllable rigid aileron is attached on the wing. The established architecture of the actuation mechanism uses four similar miniature actuators fixed inside the wing and actuating directly the flexible upper surface of the wing. The actuator was designed in-house, as there is no actuator on the market that could fit directly inside our morphing wing model. It 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

No abstract

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. Nomenclature M = Mach number AoA = Angle of attack β = Deflection angle

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.