This article focuses on the analysis and non-invasive online diagnostics of the operating condition of bearings integrated in three-phase squirrel cage induction motors, an electric machine that, due to its constructive and operational characteristics, has a significant presence in the industry.

The proposed signal-processing analysis tool is based on the non-invasive monitoring of stator electrical currents. To improve robustness in the diagnosis of bearing faults over the state-of-the-art, a hybrid approach is employed. The Short-Time Fourier Transform (STFT) and Park's Vector Approach (PVA) are combined and applied to the stator currents. The hybridisation allows benefits of both methods to be combined: i) a proper evaluation of time-varying phenomena; and ii) the possibility to distinguish the type of fault affecting the bearing.

To demonstrate the feasibility of the approach, comparisons are made between the proposed hybrid technique and both the STFT and the Extended Park's Vector Approach (EPVA), which have been previously considered in the diagnosis of these and other induction motor faults.

The validation of the proposed solutions is conducted through computational simulations and laboratory tests, ultimately aiming at generating a database of results that will initiate future research in this area. To emulate bearing failures in an experimental context, artificial damage to bearing components is introduced.

Drill strings are key components for oil and gas extraction, and also in scientific explorations, such as to reach deep sub-seafloor sediments. Drill strings are mainly composed of drill pipes, whose failure is usually triggered by fatigue. Because of this, a dedicated test rig to investigate the fatigue strength of drill pipes gives the opportunity to find design stress parameters and crack initiation sites. The University of Pisa (Italy), in collaboration with ACTA Srl (Italy), developed a resonant test rig which allows fatigue tests to be performed on drill pipe specimens, saving time and energy costs with respect to an alternative fatigue facility, such as a four-point bending testing equipment. In this resonant test rig, an eccentric mass on one side rotates at an angular speed near, but lower than the first natural frequency of the structure, thus providing a rotating bending moment on the drill pipe specimen. Several aspects of the test rig, such as the strain gauge calibration and the correct set-up of the control system, are fundamental to perform proper tests. A description of the test rig and of its various components is given in this presentation. A fatigue test series example is also presented in collaboration with JAMSTEC (Japan) who are interested in explorative drilling, especially at deep sub-seafloor locations.

The automotive industry is suffering due to interior noise propagation. These noise sources can be generated from roads, wind, and vehicle interiors. This study aims to develop a sound minimization panel for interiors using the concepts of sound reflection and sound absorption properties. In the methodology, a type of vehicle has been selected and studied for various noise-generating spots in its interiors. For analysis, a box model was built using an eltoro board with limited dimensions. A noise-level meter was inserted and the box was completely sealed to prevent the impacts of external noise. Two smartphones were connected to observe the reading inside the sealed box. To start, four different interior positions were selected, namely, the front left seat, the rear mid seat, the rear left seat, and the rear right seat. The readings were collected for the engine’s idle speed with air-conditioning “ON”, engine’s idle speed with air-conditioning “OFF”, first gear at 30 kmph, second gear at 45 kmph, and drive gear at 60 kmph in a standard road condition. With the gathered average readings for each case, a graphical plot was developed. As an improvement, rock wool and glass wool materials were superimposed in a zigzag approach. This developed material was applied inside the box model developed previously. A similar analysis was performed to identify the changes after the improvement. The results elucidated that the panel worked well, as expected. We concluded that 14.25%, 14.89%, 16.27%, 17.76%, and 17% of noise minimization, on average, could be achieved in first gear, in second gear, in drive gear, with air-conditioning “ON”, and with air-conditioning “OFF”, respectively. Though this conceptual model has limitations with the measurements, the results remained comparable. Indeed, this improvement suggested a better interior noise control mechanism for the selected vehicle.

Additive Manufacturing (AM) holds transformative potential in revolutionizing healthcare by facilitating the creation of patient-specific medical devices and apparatus. This review explores the diverse applications of AM within the healthcare sector, focusing on machines with which AM techniques can be implemented. The keywords “additive manufacturing," “healthcare sector," and “medical additive manufacturing” were searched using prominent databases like Scopus, Web of Science, and Google Scholar. The articles that met the inclusion criteria were selected for this study. Beginning with an overview of fundamental principles and technologies like stereolithography, selective laser sintering, and fused deposition modeling, along with the machines, this study delves into the fabrication of patient-specific implants, prosthetics, anatomical models, surgical guides, and drug delivery systems. Highlighting AM's ability to produce complex geometries and customize medical devices according to individual patient anatomy, case studies illustrate successful implementations, improving patient outcomes and surgical efficiency. Challenges such as regulatory hurdles and material biocompatibility are addressed alongside ongoing research efforts to enhance AM's efficacy. This study also discusses key trends and future directions, including integrating advanced materials, bioprinting techniques, and artificial intelligence to drive innovation in patient-centric healthcare solutions. This focused exploration underscores AM's potential in advancing healthcare apparatus for improved patient care.

The advent of 3D LiDAR (Light Detection and Ranging) technology has revolutionized the way moving objects are detected and tracked in various environments. Traditional systems often fall short in complex scenarios, such as poor visibility conditions or areas with unpredictable movement patterns. This necessitates an advanced solution that can accurately identify and monitor moving entities in real time, ensuring high levels of reliability and efficiency across diverse applications.

The "3D LiDAR-Based Moving Object Detection System" is designed to address these challenges by leveraging the precision of 3D LiDAR technology combined with a multi-sensor fusion approach. This system employs laser beams to create detailed three-dimensional representations of its surroundings, analyzing temporal fluctuations in data to detect and track moving objects. The integration of additional sensor inputs enhances the system's accuracy and adaptability, enabling it to operate effectively under a wide range of environmental conditions.

This paper presents a groundbreaking system that surpasses conventional detection methods, providing an invaluable tool for autonomous vehicle navigation, surveillance, security, and robotics applications. By delivering unparalleled accuracy and reliability in moving object detection, the "3D LiDAR-Based Moving Object Detection System" not only improves the safety and efficiency of these technologies but also paves the way for new advancements in the field. This represents a significant leap forward in detection and tracking technology, marking a pivotal moment in its evolution.

Pressure vessels serve as vital components for the containment of liquids or gases in various industrial applications. The utilization of pressure vessels constructed from composite materials presents a significant advantage compared to conventional vessels crafted from metal alloys or those incorporating liners, specifically, in terms of weight reduction. This attribute holds particular significance in industries such as aerospace, where it is imperative to minimize weight. By applying composite materials in pressure vessel design, substantial gains in weight reduction can be achieved, thereby contributing to enhanced performance and operational efficiency in critical aerospace applications. This work presents the mechanical design, including experimental validation, of a permeability test setup, used to estimate the permeability of composite materials used in type V aerospace pressure vessels. The test setup includes two steel chambers, between which the composite sample is placed for evaluation. During the test, the gas that the pressure vessel will hold is introduced under pressure by the receiving chamber. The other chamber (measurement chamber) serves to measure the pressure variation by a pressure transducer. With the data collected by the pressure transducer, the sample permeability can be assessed. During the design process, alternatives were also considered during the design, and the justifications of each selected and implemented solution were presented. The test setup was fabricated, and the correct operation validated. The validation of the proposed setup was accomplished using materials with different permeability characteristics, and the respective data analyzed and compared between materials and values from the literature. Permeability tests were also carried out and the results obtained were analyzed. The validation stage was successfully completed, since the obtained results from the setup agreed with those found in the literature, and the test setup was created and it is currently operational.