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Current research on Unmanned Aerial Vehicles (UAVs) is focusing on the ability of performing complex tasks by means of cooperation over many aircraft, with the scope of reducing costs and increasing the reliability. However, the use of a cooperative formation deals with several challenges to coordinate a group of autonomous vehicles. A distributed situational awareness becomes an essential requirement towards the objective. In this paper, a Decentralized Moving Horizon Estimator (DMHE) is presented with the scope of distributing the computational burden and limiting the requirements about communication and software complexity besides avoiding the vulnerability of a centralized architecture to faults. The proposed algorithm merges the consensus theory with a moving horizon estimator to overcome Kalman filtering problems in the presence of constraints on any disturbance or state variables. The decentralization of the scheme is obtained by decomposing the overall estimation problem in several optimization sub-models whose convergence is guaranteed by consensus. A preliminary sensitivity analysis was performed to evaluate the results of the proposed strategy and the significance of its main parameters.

The fire behaviour of Polymeric composite structures is one of the most critical aerospace research topics. Indeed, the exposure of Polymeric composite structures to high temperatures leads to material decomposition, associated to thermal and mechanical properties degradation. This degradation causes a reduction of the mechanical performances, which can be of main concern for safety reasons. In this paper, the tensile behaviour of Carbon Fibre Composite Polymer specimens, subjected to fire, has been experimentally and numerically investigated. The material properties degradation has been estimated according to an Arrhenius shape function, which relates the mechanical properties of the composite to the temperature. At first, static structural analyses have been carried out to assess the mechanical behaviour of the investigated specimen without fire effects. Then, a coupled thermo-structural analysis allowed evaluating the fire effect on the specimens’ mechanical and the thermal behaviour. In order to preliminary validate the proposed degradation model, the numerical results, in terms of Load versus Displacements curves, have been compared against data obtained from an ad-hoc experimental campaign where fire condition have been suitably replicated during the mechanical tests.