Combining sensor monitoring and fault tolerant control to maintain flight control system functionalities

To maintain nominal flight control system functionalities during fault scenarios, enhancements of the state-of-practise angle of attack and airspeed sensor fault accommodation strategies are presented. The strategy combines a fault detection and diagnosis (FDD) system with a robust fault tolerant control law. The FDD system allows to maintain the nominal flight control law as long as at least one angle of attack and airspeed sensor are available. The FDD system is designed using advanced nullspace computation, optimization, and signal processing techniques. For the scenario of a total airspeed measurement loss, an airspeed independent longitudinal backup control law is designed using global optimization techniques. Using this law avoids the state-of-practise switch to a direct law in which the pilot must control the Elevator positions directly. The results from an extensive industrial validation and veri�cation campaign are reported

Aircraft Wake Vortex Scenarios Simulation Package - WakeScene

Wake-vortex advisory systems and modifications of ATC procedures that aim at increasing airport capacity without compromising safety have been developed in recent years. Prior to the introduction of such systems the associated risks must be assessed. The WakeScene (Wake Vortex Scenarios Simulation) Package allows to assess the encounter probability behind different wake-vortex generating aircraft during approach and landing. WakeScene consists of modules that model traffic mix, aircraft trajectories, meteorological conditions, wake vortex evolution, and potential hazard area. This manuscript introduces the operating sequence of WakeScene, the employed sub-models and data bases, the simulation environment and evaluation tools together with the so far accomplished validation work. Examples of WakeScene applications and an outlook on further developments of the software package conclude the report

ARIA 2016 : Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle

The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma and rhinitis and (3) to develop guidelines with all stakeholders that could be used globally for all countries and populations. ARIA-disseminated and implemented in over 70 countries globally-is now focusing on the implementation of emerging technologies for individualized and predictive medicine. MASK [MACVIA (Contre les Maladies Chroniques pour un Vieillissement Actif)-ARIA Sentinel NetworK] uses mobile technology to develop care pathways for the management of rhinitis and asthma by a multi-disciplinary group and by patients themselves. An app (Android and iOS) is available in 20 countries and 15 languages. It uses a visual analogue scale to assess symptom control and work productivity as well as a clinical decision support system. It is associated with an inter-operable tablet for physicians and other health care professionals. The scaling up strategy uses the recommendations of the European Innovation Partnership on Active and Healthy Ageing. The aim of the novel ARIA approach is to provide an active and healthy life to rhinitis sufferers, whatever their age, sex or socio-economic status, in order to reduce health and social inequalities incurred by the disease.Peer reviewe

A graphical user interface for flight control development

The FSA (First Shot Approach) Demonstrator of DLR and DASA/Airbus is a first prototype for an integrated multidisciplinary environment for flight control developement. The FSA Demonstrator represents a state-of-the-art computational tool which facilitates the study of trade-off between competing specifications and performance metrics. It integrates an object-oriented modeling environment, a data and tool management system, general purpose system analysis, simulation and synthesis tools and an automatic multi-goal attainment optimization program. The FSA Demonstrator comes with a dedicated graphical user interface for problem setup and pushbutton program operation which allows easy setup an operation even by non-specialists. The main payoffs of the FSA are a significant reduction in the design cycle and an improved performance of handling qualities

Design of Robust Dynamic Inversion Control Laws using Multi-Objective Optimization

The design of robust attitude control laws for a civil aircraft with nonlinear dynamic inversion and multiobjective optimization is discussed. Dynamic inversion is a methodology that achieves linearization and decoupled command responses of the closed-loop system via inverse model equations in the feedback loop. Using a linear outer loop controller the desired dynamic behavior is imposed. For tuning the free controller parameters, multi-objective optimization is used. The required robustness is achieved via a multi-model approach, as well as local robustness measures (e.g. gain and phase margins) as optimization criteria. As a new approach, not only the linear controller gains are optimized, but also physical parameters in the inverse model that are considered uncertain in the design model. The resulting control laws are used as inner loops of an autoland system, which was assessed for JAR-AWO requirements and successfully flight tested

Enhanced detection and isolation of angle of attack sensor faults

An enhanced detection and isolation method to monitor the state-of-practice triplex redundant angle of attack measurements on modern civil transport aircraft is presented. The developed fault detection and diagnosis architecture relies on advanced model and signal based techniques monitoring each of the three sensors individually. This allows the correct isolation of erroneous sensors also in case of multiple sensor faults. The gathered isolation information is used in an advanced sensor fusion scheme, allowing the propagation of an adequate angle of attack value to the flight control computer in case of failure. The fault detection and diagnosis system is validated using a high �delity benchmark model of a large commercial transport aircraft using different wind excitations together with challenging pilot and auto-pilot scenarios

Worst-case parameter search based clearance using parallel nonlinear programming methods

This chapter presents the theoretical background for several enhancements of the worst-case parameter search based clearance of flight control laws. The worst case search method aims to find combinations of parameters and flight conditions for which the clearance criteria are mostly violated or poorly satisfied. The two main aspects for the proposed enhancements are: (1) increasing the reliability of clearance by the application of global optimization methods in conjunction with established simulation and analysis tools; and (2) increasing the efficiency of clearance by applying parallel computation techniques

MOPS - Multi-Objective Parameter Synthesis, User’s Guide V6.6

The quality assessment of (complex) technical systems is carried out with many different criteria, as for example performance behaviour, energy consumption or reliability. With a model based design optimization the different objectives concerning the desired system behaviour are included directly into the system design at an early stage. Generally, when using optimisation for design the designer translates his specifications for the system design into respective evaluation criteria and declares those parameters which are disposable for design. By specifying demands for each criterion a design direction is prescribed. Within different iteration steps optimization algorithms automatically generate best possible solutions compromising the design demands