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Item type:Publication, Access status: without files , On the effect of enforcing stability in model predictive control for gust load alleviationGust load alleviation control refers to the task of attenuating loads acting on an aircraft flying through turbulence. Simulation studies have shown that model predictive control based gust load alleviation strategies can lead to significant load reduction. Application of control strategies in airplanes requires guarantees with respect to reliability, safety, as well as stability. We present nominal stability guarantees for predictive gust load alleviation that are based on terminal penalties and that require no terminal constraint. Furthermore, we analyze the influence of the stabilizing terminal penalty on the achievable load reduction. To this end, we draw upon standard gust types and a fully flexible aircraft model with unsteady aerodynamics that is used as simulated reality.Publicationtype: Conference Paper8 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Gust load alleviation based on model predictive control(Royal Aeronautical Society, 2013); ; ; Weight reduction is a typical design goal for modern aircraft. If gust encounters (as required by Certification Specification 25) are sizing conditions of parts of the airframe, this can be achieved (for example) by an active gust load alleviation system that reduces the gust load level down to the level of the next design condition, which might be the design loads from maneuver conditions. In order to design an efficient gust load alleviation system that respects the actuation constraints of the control surfaces, uses preview information on the incoming gust shape from a Light Detection And Ranging gust sensor and takes gust propagation delays into account, we apply model predictive control to an aeroservoelastic aircraft model.Publicationtype: Conference Paper16 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Model predictive control for gust load alleviation(Elsevier, 2012); ; ; For economical and ecological reasons aircraft are required to become more efficient by reducing fuel consumption and CO2 emissions. One way to achieve these objectives is to decrease the weight of the aircraft structure. The reduction is, however, limited by the structural requirement that the aircraft must be able to withstand the forces and stress induced by maneuvers, turbulence, and gusts. Reduction of the forces and stress, for example by suitable ight control schemes, allows lighter structures and thus more efficiency. In this paper we focus on the problem of alleviating gust loads at critical locations of the airframe. This is accomplished via a model predictive control approach that accounts for look ahead measurements of incoming gust disturbances via light detection and ranging (LIDAR) systems. Deecting control surfaces are used by the predictive controller to reduce the load effects caused by the disturbance, the aircraft rigid body, and the structural response. The proposed controller design takes actuator deection- and rate-limitations, the complex multiple- inputs multiple-outputs system structure, and the objective to reduce critical loads directly into account. Predictive control proved itself to be an effective control strategy for gust load alleviation. © 2012 IFAC.Publicationtype: Conference Paper24 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Event-based reduced-attention predictive control for nonlinear uncertain systemsEvent-based control is an alternative to traditional control where new measurements are sampled only if critical events occur. This not only allows to reduce the control effort but it satisfies nowadays application requirements, such for example reduction of information exchange, computational power, or energy consumption. The work in this field is, however, still sparse and only a few results are available. Properly choosing an event-detection logic can considerably improve the overall system's performance. We propose a control algorithm which makes use of a model-based triggering strategy to reduce the control effort (reduced-attention control), while guaranteeing robustness against bounded additive perturbations for nonlinear continuous time systems. In particular, we derive conditions which guarantee that asymptotic stability of the nominal system implies practical stability of the real one in a neighborhood of the origin. A continuous stirred tank reactor is used as a benchmark problem to show the effectiveness of the presented algorithm.Publicationtype: Conference Paper13 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Event-based model predictive control for networked control systemsThanks to their cheap startup costs, flexibility, and standard infrastructure re-usability, Networked Control Systems have gained the attention of both the control community and the industry. Unfortunately, the presence of communication networks might introduce nondeterminism due to (random) delays and/or (unpredictable) information losses. In this paper, an event-based model predictive control approach for nonlinear continuous time systems under state and input constraints is presented. This method is able to counteract bounded delays, information losses, as well as deal with event triggering due to sensors and actuators. Under standard weak assumptions, closed loop stability, in the sense of asymptotic convergence, is achieved. Simulation results for a planar vertical takeoff and landing aircraft are provided.Publicationtype: Conference Paper15