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Automatic landing system is a system that can allow an aircraft to land in a totally autonomous manner taking advantage of auxiliary instruments such as the instrument landing system and the radio altimeter. A controller based on the simple adaptive architecture is numerically investigated in this work as an alternative Autoland system. A velocity control is implemented in such a way to ensure that the aircraft will land with the proper sinking rate. The adaptability of the proposed controller is studied by considering a gust disturbance and analyzing its effect on several landing performance indexes. [ABSTRACT FROM AUTHOR]

This work aims to present an alternative time domain modeling approach for preliminary flutter analysis of wings equipped with trailing edge control surfaces. The proposed modeling approach is based on the formulation of an aeroelastic beam finite element that relies on Euler-Bernoulli beam theory and De Saint Venant torsion theory for the structural part and on Theodorsen theory for aerodynamics. The modeling approach here presented is useful for preliminary aeroelastic analysis and it could be readily implemented in existing beam finite elements-based codes. [ABSTRACT FROM AUTHOR]

In order to increase the operability range of wings in terms of speed, the suppression of aeroelastic vibrations due to flutter phenomena using a trailing edge flap is analysed. The aeroelastic modelling of a three degrees of freedom airfoil in incompressible flow is presented and an augmented state space representation is used for the time domain analysis of the problem. A finite element model of a V stack piezoelectric actuator, used to move the trailing edge flap, is introduced. A heuristic method named Particle Decline Swarm Optimization for the tuning of the filtered PID controller parameters for different velocity values is used. A stochastic robustness analysis is carried out to verify the robustness to parameters uncertainties of the proposed flutter suppression system. [ABSTRACT FROM AUTHOR]

A Simple Adaptive Controller (SAC) is proposed in this paper to realise a fault-tolerant flight control system capable of leading the pitch motion of an aircraft. The primary condition for obtaining a stable adaptive controller with an output error asymptotically stable is that the plat be Almost Strictly Positive Real (ASPR). Since considered aircraft dynamics equations do not satisfy such requirement, a Parallel Feedforward Compensator (PFC) is adopted to let the augmented system achieve the ASPR condition. The invariant gains of the SAC are computed by using the Population Decline Swar Optimization (PDS O), a modification of the Particle Swarm Optimization (PSO). It is characterize by the fact that the initial size of the swarm undergoes during the iteration loop a decline demographic model to speed up the optimisation procedure. Flight mechanics results are presented to show the capability of the proposed scheme to control the aircraft pitch motion under an elevator command input. [ABSTRACT FROM AUTHOR]

Among the causes of increasing fatigue stress of an aircraft Nose Landing Gear NLG it is to be mentioned the shimmy vibration. The active control of shimmy can lead toward a solution capable to adapt to environment variations and system uncertainties. In this work an adaptive shimmy damping system based on the Modified Simple Adaptive Control MSAC is proposed. The Almost Strictly Passivity requirements is fulfilled by means of Parallel Feedforward Compensator PFC. The controller is designed by using the linearized plants while simulations to asses the controller soundness are carried out by considering the nonlinearities as disturbances. Results of aeronautical interests are presented. [ABSTRACT FROM AUTHOR]

An alternative continuous particle swarm optimization model will be presented in order to improve the standard particle swarm optimization. The main idea is to extend the discrete formulation in the continuous time space describing the bird flying motion evolution as a continuous time function, solution of a Cauchy problem defined by a second order ordinary differential equation associated with random initial conditions. A convergence analysis of the algorithm will be presented as well as a comparison with the discrete algorithm in terms of performance and computational time. [ABSTRACT FROM AUTHOR]

The topic related to the vibration transmission from a transportation mean to the human body is of primary importance since nowadays more and more people are constantly on travelling for many reasons and, among the transportation systems, air travel is growing up representing an increasing opportunity for airlines. Since high doses of vibrations can cause discomfort or sickness, it is necessary to correctly design seats and passenger cabins according to some vibration threshold. In order to develop a general and reliable model to estimate the vibration doses transmitted to the human body during air transportation, an uncertain parameter 4 Degrees of Freedom anthropometric model has been developed in this paper. Thanks to Improved Interval Analysis, it has been possible to estimate the response interval of the model in frequency domain to be used for comfort evaluation purposes. [ABSTRACT FROM AUTHOR]