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In the architecture of an Unmanned Aerial Vehicle (UAV), a crucial component responsible for the propulsion system is the electric motor. Over the years, different types of electric motors, including Brushless Direct Current (BLDC), have supported the UAV’s propulsion system in diverse configurations. However, in the context of flux flow, the Radial Flux Permanent Magnet Motor (RFPMM) has been given more priority than the Axial Flux Permanent Magnet Motor (AFPMM) due to its sustainability in design and construction. Nevertheless, the AFPMM boasts higher speed, power density, lower weight, and greater efficiency than the RFPMM, because of its shorter flux path and the absence of end-turn winding. Therefore, this paper focuses on conducting a suitability analysis of an AFPMM as a shaft-connected propeller-mounted motor, with the intention of replacing the RFPMM in UAV applications.

This research employs a comprehensive methodology to explore hypersonic boundary layers' stability and transition dynamics, focusing specifically on the influence of sharp and blunt leading edges. The Stanford University Unstructured (SU2) Computational Fluid Dynamics (CFD) solver is utilized to compute the mean flow over a flat plate, establishing a foundational basis for subsequent stability analysis. The extracted boundary layer profiles undergo validation against existing literature, ensuring accuracy and reliability. Further analysis is conducted using a Python code to generate input files for the Linear Stability Solver. The Linear Stability Solver analysis constitutes a crucial phase wherein the research delves into the eigenvalue spectra, identifying dominant modes and closely scrutinizing the role of the modes in the transition process within the hypersonic boundary layers.

For spacecraft whose missions are considered low risk, it is typical for units to be subjected to unit-level thermal cycle and thermal vacuum testing. In recent years, however, the desire to reduce program costs and shorten development schedules has the aerospace testing community questioning the value of thermal vacuum testing all units. There may be instances where unit-level thermal vacuum testing is unnecessary if it can be shown that the unit’s design and performance is insensitive to the vacuum environment and that failures associated with the vacuum environment can be detected in other unit-level testing. The prescription of conditions under which unit thermal vacuum testing may be exempted should focus on establishing proven heritage, demonstrating design robustness through analysis and development testing, and reducing incurred risk. A general list of considerations by which vacuum-sensitivity may be assessed is provided herein.

Battery electric vehicles are quickly gaining momentum to improve vehicle fuel efficiency and emission reduction. However, they must be designed to provide adequate range on a single charge combined with good acceleration performance, top speed, gradeability, and fast charging times. The paper presents a model for sizing the power train of an electric vehicle, including the power electronic converter, electric motor, and battery pack. A major assumption is that an optimal wheel slip rate can be achieved by modern vehicles using slip control systems. MATLAB/Simulink was used to model the vehicle powertrain. Simulations were conducted based on different speed and acceleration profiles. The purpose of the study focused on the motor and power electronics sizing requirements to achieve optimal range and performance.

In recent decades, research based innovative system-on-chip (SoC) design has been a very important issue, due to the emerging trends and application challenges. The SoCs encompass digital, analog and mixed-signal hardware and software components and even sensors and actuators. Modelling and simulation constitute a powerful method for designing and evaluating complex systems and processes for many analysts and project managers as they engage in state of-the-art research and development. Modelling and simulations not only help them with the algorithm or concept realization and design feasibility, but it also allows experimentation, optimization, interpretation of results and validation of model.

Lunar tubes, natural underground structures on the Moon formed by ancient volcanic activity, offer natural protection from extreme temperatures, radiation, and micro-meteorite impacts, making them prime candidates for future lunar bases. However, the exploration of lunar tubes requires a high degree of mobility. Given the Moon's gravity, which is approximately six times weaker than Earth's, efficient navigation across rugged terrains within these lava tubes is achievable through jumping. In this work, we present the design of subsystems for a miniature hexapod rover weighing 1 kg, which can walk, jump, and stow. The walking system consists of two subsystems: one for in-plane walking, employing four single-degree-of-freedom (DOF) legs utilizing the KLANN walking mechanism, and another for directional adjustments before jumping. The latter employs a novel three-DOF mechanism employing a cable pulley mechanism to optimize space utilization.

The finite element method is one of the most robust tools in structural analysis. Typically, the input parameters in a finite element model are assumed to be deterministic. However, in practice, almost all material and geometrical properties, including the load, possess randomness. The consideration of the probabilistic nature of these quantities is essential to effectively designing a system that is robust against the uncertainties arising due to the variation in the input parameters, the significance of which has been documented by NASA in “Probabilistic Risk Assessment Procedures Guide for NASA Managers and Practitioners”, 2011. Among the various techniques applicable for stochastic analysis, the perturbation method, which is based on a sound mathematical foundation derived from Taylor’s series expansion, is widely acknowledged for its much higher efficiency compared to the well-known Monte-Carlo method.

Replacement of chromium containing materials and processes is the focus of extensive research and development activity due to increasingly stringent environmental regulations stemming from hexavalent chromium toxicity concerns. This, in turn, has increased the cost of hardware manufacture. This paper describes the efforts of Boeing Commercial Airplanes in developing a more environmentally suitable alternative process to chromic acid anodizing. Several alternative processes were evaluated prior to selection of a boric-sulfuric acid anodize (BSAA) process. Results of screening tests (including corrosion resistance, paint adhesion, abrasion resistance and fatigue life) and subsequent BSAA process optimization are included.

Under complex and extreme operating conditions, the road adhesion coefficient emerges as a critical state parameter for tire force analysis and vehicle dynamics control. In contrast to model-based estimation methods, intelligent tire technology enables the real-time feedback of tire-road interaction information to the vehicle control system. This paper proposes an approach that integrates intelligent tire systems with machine learning to acquire precise road adhesion coefficients for vehicles. Firstly, taking into account the driving conditions, sensor selection is conducted to develop an intelligent tire hardware acquisition system based on MEMS (Micro-Electro-Mechanical Systems) three-axis acceleration sensors, utilizing a simplified hardware structure and wireless transmission mode. Secondly, through the collection of real vehicle experiment data on different road surfaces, a dataset is gathered for machine learning training.

The European Union’s Horizon 2020 programme has funded the SENS4ICE (Sensors for Certifiable Hybrid Architectures for Safer Aviation in Icing Environment) project [1], an innovative approach for the development and testing of new sensors for the detection of supercooled large droplets (SLD). SLD may impinge behind the protected surfaces of aircraft and therefore represents a threat to aviation safety. The newly developed sensors will be tested in combination with an indirect detection method on two aircraft, in two parallel flight programs: One on the Embraer Phenom 300 in the U.S. and one on the ATR-42 in Europe. In this framework the Deutsches Zentrum für Luft- und Raumfahrt (German Aerospace Center) is in charge of the airborne measurements and data evaluation of the microphysical properties of clouds encountered during the SENS4ICE field campaigns in February, March and April 2023.

In the European FULMEN program, a collection together with an analysis of available data on lightning have been collected in a public database produced by Aerospatiale. This database contains data on In-flight and ground measurements, on In-flight incidents and manufacturer transfer functions. In this paper, the data of the in-flight measurements are presented. The In-flight data have been extracted from the Convair and Transall campaigns performed during summer 1985 and 1988 respectively. The measurements have shown that a lightning strike to an aircraft can be decomposed into four main phases: (1) the pre-breakdown phase associated with the general electrostatic condition just before the lightning, (2) the leaders development phase, (3) the recoil streamers phase and (4) the continuous current phase. For each phase, the main physical parameters (current, number of impulse current, impulse period, impulse duration, electric field, …) have been collected.

MOSA (Modular Open System Approach) provides a framework for efficient and sustainable design of complex integrated systems. In domain of embedded technology, the MOSA as-is does a good job in identifying modular software and hardware frameworks required to establish a common baseline for generic open architecture. On the other hand, it does not cover physical aircraft integration, integration methodology and other constituent elements essential for design of robust interfaces and integrated embedded systems, which are owned by OEMs and their suppliers. The definition of open interfaces is a key constituent in definition of MOSA-compliant architectures. An efficient system integration lifecycle requires unambiguous interfacing among hosted functions. Open interfaces and Ethernet are core system integration technologies and should be integrated and configured with other software/hardware framework elements, to enable hard RT, real-time and soft-time application hosting.

Additive manufacturing (AM) is a common way to make things faster in manufacturing era today. A mix of polypropylene (PP) and carbon fiber (CF) blended filament is strong and bonded well. Fused deposition modeling (FDM) is a common way to make things. For this research, made the test samples using a mix of PP and CF filament through FDM printer by varying infill speed of 40 meters per sec 50 meters per sec and 60 meters per sec in sequence. The tested these samples on a tribometer testing machine that slides them against a surface with different forces (from 5 to 20 N) and speeds (from 1 to 4 meters per sec). The findings of the study revealed a consistent linear increase in both wear rate and coefficient of friction across every sample analyzed. Nevertheless, noteworthy variations emerged when evaluating the samples subjected to the 40m/s infill speed test.

This paper reports the development of an operation support system for production equipment using image processing with deep learning. Semi-automatic riveters are used to attach small parts to skin panels, and they involve manual positioning followed by automated drilling and fastening. The operator watches a monitor showing the processing area, and two types of failure may arise because of human error. First, the operator should locate the correct position on the skin panel by looking at markers painted thereon but may mistakenly cause the equipment to drill at an incorrect position. Second, the operator should prevent the equipment from fastening if they see chips around a hole after drilling but may overlook the chips; chips remaining around a drilled hole may cause the fastener to be inserted into the hole and fastened at an angle, which can result in the whole panel having to be scrapped.

Many tests have shown that engine oil pumps are the limiting factor in providing satisfactory high-altitude aircraft oil system performance. As is pointed out in this paper, it is for this reason that both reciprocating and gas turbine engine manufacturers should design and provide their engines with a pump that will give satisfactory performance at an inlet pressure of 2 in. of Hg absolute with 10% (by volume) entrained air. Of the various oil systems investigated by the AMC, the closed-circuit system seemed to be most desirable in terms of both performance and installation, for use in high-altitude operational aircraft.

This paper defines the geometry of minimum weight tank structures of given enclosed volume. A tank structure is considered to comprise a circular cylindrical shell (monocoque or stiffened), bulkheads, and skirt structures. The analyses, starting from established criteria of failure, apply to the loading cases of longitudinal compression and bending moments in combination with internal pressure. The bulkhead geometries are flat, hemispherical, and ellipsoidal. For monocoque shells, the analyses yield the radius and wall thicknesses prescribing a minimum total weight of cylindrical tank wall, bulkheads, and skirts (unpressurized cylindrical appendages, for example, interstage structure). For stiffened shells, the analyses yield the tank radius, skin gauge, stringer spacing, and frame spacing prescribing a minimum total tank weight. An optimum relative geometry is defined for three types of stringers.