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Additive Layer Manufacturing (ALM) is a very promising manufacturing technology, which makes possible to produce components that would not have even been possible just a few years ago. Metal powder additive manufacturing produces three-dimensional parts layer by layer. This allows for almost a complete freedom of design and it overcomes the traditional limits of subtractive manufacturing techniques, such as CNC. The design process can also incorporate the use of topological optimization software, making it also possible to obtain higher integration with respect to machined parts, thus minimizing the number of components to be assembled, with advantages in terms of material waste and energy consumption. The present paper intends to be an overview of the approach which aims to guarantee the safety of flight of metal Additive layer manufactured parts of the fuel storage system of a Civil Tilt Rotor Technology Demonstrator under development in the framework of EU Clean Sky 2. Since the flight tests are already scheduled, the technologies that will be taken on-board will reach TRL6 at least. The parts under investigation are the metallic flanges, which connect the fuel hoses system to the fuel storage system (which are bladder tanks installed in the wing bays). A flowchart of the testing activities, aiming to guarantee the safety of flight, is presented, along with manufacturing, experimental and NDI results., Presented at 47th European Rotorcraft Forum, United Kingdom, 7-9th September, 2021

The presentation briefly describes the crashworthiness approaches followed in the collaborative projects T-WING and DEFENDER, funded by Clean Sky2 in the framework of EU Horizon2020 program., Contribution presented in the EVTOL CRASHWORTHINESS WORKSHOP (https://nari.arc.nasa.gov/crashworthiness)

In this retrospective study authors present the cases treated with allograft transplantation for ligament reconstruction in chronic ankle instability. Methods From January 1999 to December 2016, 72 patients were operated , including 29 women and 43 men, aged between 22 and 47 (average 29.5). Of the 72 patients treated, 61 were evaluated in the follow up (12 months-12 years, with an average of 59 months) with clinical and radiographic evaluation, AFASS score (American Foot and Ankle Society Scoring System) and grading according to Good et al. Results There were no cases of transplant infection or rejection. Based on the criteria of Good et al., the results were excellent or good in the 57 patients operated with semitendinosus or frozen fresh gracil, sufficient in the 3 transplant cases of freeze-dried semitendinosus and 1 case of bad result. Conclusion Transplantation with allograft in chronic ankle instability represents an "innovative" technique that has achieved good results even in young patients with sporting needs. Level of Evidence: 3. Retrospective study, Archives of Medicine & Surgery University of Milan, V. 1 N. 1 (2020)

The work evaluates the capability of explicit FE commercial codes in simulating dynamic events with continuum and fluid parts and their mutual interaction.

We have fabricated and characterized at low temperatures Nb/Ni/(Al/Ni)14/Nb lateral junctions and Nb micro-SQUIDs involving (Al/Py)10 multilayers (here Py is permalloy: 80% Ni − 20% Fe). We have studied - curves and Josephson critical current as a function of an external magnetic field Ic(H) at various temperatures and orientations of the applied magnetic field. These studies revealed that, for some orientations of the externally applied magnetic field, the Ic(H) dependence of the lateral junctions has a component highly sensitive to magnetic field. In addition, we have observed a SQUID-like Ic(H) dependence for devices, in which an orthogonally oriented (with respect to the substrate) Nb loop that includes two nanoscopic Josephson junctions is filled with a (Al/Py)10 multilayer. We believe the devices presented here are promising as magnetic field sensors on nanoscale for various applications where high spatial resolution is required

Aluminum Josephson junctions are the building blocks for the realization of superconducting quantum bits. Attention has been also paid to hybrid ferromagnetic Josephson junctions, which allow switching between different magnetic states, making them interesting for applications such as cryogenic memories, single-photon detectors, and spintronics. In this paper, we report on the fabrication and characterization of high-quality ferromagnetic Josephson junctions based on aluminum technology. We employed an innovative fabrication process inspired by niobium-based technology, allowing us to obtain very high-quality hybrid aluminum Josephson junctions; thus, supporting the use of ferromagnetic Josephson junctions in advanced quantum circuits. The fabrication process is described in detail and the main DC transport properties at low temperatures (current–voltage characteristic, critical current as a function of the temperature, and the external magnetic field) are reported. Here, we illustrate in detail the fabrication process, as well as the main DC transport properties at low temperatures (current–voltage characteristic, critical current as a function of the temperature, and the external magnetic field).

We propose to exploit currently available tunnel ferromagnetic Josephson junctions to realize a hybrid superconducting qubit. We show that the characteristic hysteretic behavior of the ferromagnetic barrier provides an alternative and intrinsically digital tuning of the qubit frequency by means of magnetic field pulses. To illustrate functionalities and limitation of the device, we discuss the coupling to a read-out resonator and the effect of magnetic fluctuations. The possibility to use the qubit as a noise detector and its relevance to investigate the subtle interplay of magnetism and superconductivity is envisaged.

The main objective of this paper is to describe a methodology to be applied in the preliminary design of a tiltrotor wing based on previously developed conceptual design methods. The reference vehicle is the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD) developed by Leonardo Helicopters within the Clean Sky research program framework. In a previous work by the authors, based on the specific requirements (i.e., dynamics, strength, buckling, functional), the first iteration of design was aimed at finding a wing structure with a minimized structural weight but at the same time strong and stiff enough to comply with sizing loads and aeroelastic stability in the flight envelope. Now, the outcome from the first design loop is used to build a global Finite Element Model (FEM), to be used for a multi-objective optimization performed by using a commercial software environment. In other words, the design strategy, aimed at finding a first optimal solution in terms of the thickness of composite components, is based on a two-level optimization. The first-level optimization is performed with engineering models (non-FEA-based), and the second-level optimization, discussed in this paper, within an FEA environment. The latter is shown to provide satisfactory results in terms of overall wing weight, and a zonal optimization of the composite parts, which is the starting point of an engineered model and a detailed FEM (beyond the scope of the present work), which will also take into account manufacturing, assembly, installation, accessibility and maintenance constraints.

The T-WING project is a Clean Sky 2 research project aimed at designing, manufacturing, qualifying and flight-testing the new wing of the Next-Generation Civil Tiltrotor Technology Demonstrator (NGCTR-TD), as part of the Fast Rotorcraft Innovative Aircraft Demonstrator Platforms (FRC IADP) activities. Requirements, design strategy, methodology and main steps followed to achieve the composite wing preliminary design are presented. The main driving requirements have been expressed in terms of dynamic requirements (e.g., limitations on natural frequencies), aeroelastic requirements, i.e., compliance with European Aviation Safety Agency (EASA) CS-25 and CS-29 Airworthiness Requirements), structural requirements (e.g., target wing structural mass), functional requirements (e.g., fuel tanks, accessibility, assembly and integration, etc.) and wing preliminary loads. Based on the above-mentioned requirements, the first design loop is performed by targeting an optimal wing structure able to withstand preliminary design loads, and simultaneously with stiffness and inertia distributions leading to a configuration free from flutter within the flight envelope. The outcome from the first design loop is then used to refine the model and compute more reliable flight loads and repeat aeroelastic analysis, returning further requirements to be fulfilled in terms of wing stiffness and inertia distributions. The process is iterated till the fulfillment of all the project requirements.