Low-order models and numerical techniques for the analysis of rotorcraft flight mechanics

The dissertation describes (i) a mathematically rigorous approach for the derivation and validation of low-order helicopter mathematical models from first principles and (ii) the development or improvement of a set of numerical techniques that provide computationally efficient and reliable tools for the analysis of rotorcraft flight mechanics, and in particular evaluation of maximum performance and assessment of handling qualities. Simplified models are expected to provide results at a fraction of the computational cost required for performing the same analysis on the basis of higher order models, but, at the same time, the reliability of these results needs to be carefully assessed, which is one of the objectives of the present work. The techniques developed are tested on various single main rotor rotorcraft configurations, with a focus on articulated, teetering, and two-bladed-gimballed rotor

Model predictive control architecture for rotorcraft inverse simulation

A novel inverse simulation scheme is proposed for applications to rotorcraft dynamic models. The algorithm adopts an architecture that closely resembles that of a model predictive control scheme, where the controlled plant is represented by a high-order helicopter model. A fast solution of the inverse simulation step is obtained on the basis of a lower-order, simplified model. The resulting control action is then propagated forward in time using the more complex one. The algorithm compensates for discrepancies between the models by updating initial conditions for the inverse simulation step and introducing a simple guidance scheme in the definition of the tracked output variables. The proposed approach allows for the assessment of handling quality potential on the basis of the most sophisticated model, while keeping model complexity to a minimum for the computationally more demanding inverse simulation algorithm. The reported results, for an articulated blade, single main rotor helicopter model, demonstrate the validity of the approach

Personalization, verification and conformance for logic-based communicating agents

This paper is an overview of the work that we have carried on in the last two years in the context of the MASSiVE project. The main research lines have concerned personalization of the interaction with web services, personalization of courseware, web services interoperability, and integrated environments for agent oriented software engineering. All of them can be seen as applications of different reasoning techniques to a declarative specification of interaction. A declarative specification makes the study of properties easy and allows a fast prototyping of applications. In particular, we applied reasoning about actions and change to the personalized selection and composition of web services and to the construction of courseware that satisfies the user's needs and goals. This kind of reasoning has also been integrated in the DCaseLP MAS prototyping environment. Declarative specifications have also been helpful to face the problem of proving policy conformance in a way that guarantees web service interoperability. Finally, the adoption of process languages for web services for expressing the procedural behavior of adaptive BDI-style agents have been explored