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Unmanned Aerial Vehicles (UAVs) have been used extensively in many applications, such as surveillance, medical transportation and delivery tasks. These applications usually involve an attachment system to connect a payload. However, when connected to such a coupled system, the UAV exhibits lower flight performance mainly due to gust loads. Mathematical modeling is used in this paper to illustrate the comparison between an UAV with a coupled system and a conventional UAV. Proportional Derivative (PD) and Sliding Mode Control (SMC) approaches are used to evaluate the vibrations of the payload, and the UAV trajectory subjected to Dryden gust. This work therefore uses these methods to investigate the dynamic response of a quadrotor-type UAV equipped with a payload and a flexible attachment system. [ABSTRACT FROM AUTHOR]

The paper presents the design and experimental testing of the control system used in a new morphing wing application with a full-scaled portion of a real wing. The morphing actuation system uses four similar miniature brushless DC (BLDC) motors placed inside the wing, which execute a direct actuation of the flexible upper surface of the wing made from composite materials. The control system of each actuator uses three control loops (current, speed and position) characterised by five control gains. To tune the control gains, the Particle Swarm Optimisation (PSO) method is used. The application of the PSO method supposed the development of a MATLAB/Simulink® software model for the controlled actuator, which worked together with a software sub-routine implementing the PSO algorithm to find the best values for the five control gains that minimise the cost function. Once the best values of the control gains are established, the software model of the controlled actuator is numerically simulated in order to evaluate the quality of the obtained control system. Finally, the designed control system is experimentally validated in bench tests and wind-tunnel tests for all four miniature actuators integrated in the morphing wing experimental model. The wind-tunnel testing treats the system as a whole and includes, besides the evaluation of the controlled actuation system, the testing of the integrated morphing wing experimental model and the evaluation of the aerodynamic benefits brought by the morphing technology on this project. From this last perspective, the airflow on the morphing upper surface of the experimental model is monitored by using various techniques based on pressure data collection with Kulite pressure sensors or on infrared thermography camera visualisations. [ABSTRACT FROM AUTHOR]

The current flight management system (FMS), CMA-9000, from CMC Electronics-Esterline, only optimises the vertical flight profile in terms of the speed of the aircraft. This article defines a methodology that optimises the speeds and altitudes for the vertical profile, obtaining a trajectory that reduces the global flight cost. The performance database (PDB) provided by CMC Electronics-Esterline is presently used on aircraft such as the Lockheed L-1011, the Airbus A310 and the Sukhoi Superjet 100 Russian regional jet. The PDB is used as the reference to design different trajectory optimisation algorithms to obtain the altitude where the aircraft fuel efficiency is the best. These algorithms are compared with the part-task trainer (PTT), simulator that represents the FMS CMA-9000, supplied by CMC Electronics-Esterline as well. To validate the results, the FlightSIM® software is used, which considers a complete aircraft aerodynamic model for its simulations, giving accurate results and very close to reality. [ABSTRACT FROM AUTHOR]

This article presents a new method to obtain a miniaturized intelligent gyro sensor. The proposed method uses a fuzzy logic controller to realize an online correction of the error due to the gyro sensor’s bias variation with temperature. In the first phase, gyro experimental testing is performed for various speeds ranging from −150 to 150°/s and temperatures between −10 °C and 70 °C, and the results obtained with classical compensation methods are evaluated. The fuzzy logic controller is developed via a fuzzy inference system (FIS), generated from the gyro testing experimental results. Further, to optimize the membership function parameters of its input–output variables, the FIS is trained with a neuro-fuzzy network. Validation by the assessment of errors shows that the proposed method gives better results than the classical algorithms based on the least squares method. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The main objective of this research work is the development of an actuation control concept for a new morphing actuation mechanism made of smart materials, which is built from a shape memory alloy (SMA). Two lines of smart actuators were incorporated to a rectangular wing to modify the upper wing surface, made of a flexible skin, with the intention to move the laminar-to-turbulent transition point closer to the wing trailing edge.After a brief introduction of the morphing wing system architecture and requirements, the actuation lines' design and instrumentation are presented. The integrated controller controls the SMA actuators via an electrical current supply, so that the transducer position can be used to eliminate the deviation between the required values for vertical displacements (corresponding to the optimized airfoils) and their physical values. The final configuration of the integrated controller is a combination of a bi-positional (on–off) controller and a PI (proportional–integral) controller, due to the two heating and cooling phases of the SMA wires' interconnection. This controller must behave like a switch between the cooling and the heating phases, situations where the output current is 0 A, or is controlled by a PI type law. The PI controller for the heating phase is optimally tuned using integral and surface minimum error criteria (Ziegler–Nichols). The controller is numerically tested on the linear identified system in terms of time response, Bode diagram, amplitude and phase stability margins, and root-locus. [ABSTRACT FROM AUTHOR]