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Filament wound pressure vessels have a characteristic pattern observed in their helical layers. These are mosaic‐shaped patterns and affect the layer structural behavior. The present research aims to focus on the influence of mosaic patterns on stress‐strain field and structural design of thin‐walled internally pressurized filament wound pressure vessel. The widely used stress analysis procedures and the commercially available finite element tools usually neglect the effect of the mosaic patterns. The present work seeks to deal with the modeling and stress analysis of complete pressure vessel, incorporating mosaic patterns.

The incorporation of the mosaic effect provides more realistic modeling of the real stress distribution and the stress values compared to the conventional analyses (the effect would depend on the shell structure, i.e. number of plies, relative thicknesses, etc.). The structural analysis is performed using commercial finite element analysis (FEA) tools ANSYS.

The comparison of results of analytical solution and conventional FEA provides close values of the stresses in the plies. As for the stress and strain distributions obtained by incorporating the effect of mosaic patterns are considerably different. The distribution of the stress and strain fields are not uniform along the length of the vessel and along its circumference and the maximum stresses acting in the direction of the fibers are higher than those calculated using conventional FEA techniques.

Previous work was limited to composite cylindrical shells, without incorporating the end domes. The present work deals with the modeling and stress analysis of complete pressure vessel, incorporating mosaic patterns.

Currently, the majority of designed robots are not well‐matched to their applications because designers do not employ a clear and organized design process. Additionally, the high cost of robotic systems makes it difficult to financially justify the use of this technology. The purpose of this paper is to present a new design process that gathers conceptual, kinematic and dynamic design, finite elements method (FEM), functional design and virtual reality control. Furthermore, kinematic and dynamic design can be obtained by traditional theory or standard computer tools (SCT) to accelerate the design. Through SCT fitted mathematical models and non‐mathematical virtual models may be acquired.

This paper investigates the design process of a robot. First, the entire methodology is presented (including two new techniques for solving the kinematic and dynamic questions via SCT). Second, a case study using Autodesk^® Inventor™ has been analysed to assess the feasibility of the method and techniques.

The more stages of the design process are considered, the more successful solutions become. Designers can obtain a mathematical solution for an analytically unsolvable robot fitting a mathematical model by SCT. To obtain a rapid design, designers must consider using SCT and following just in need (JIN) philosophy to find a non‐mathematical virtual model.

This paper presents an innovative guide for robotic engineers and researchers which covers the whole design process and new techniques for obtaining mathematical and non‐mathematical solutions.

The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

The purpose of this study is to describe the design and validation of a three-dimensional (3D)-printed phantom of a uterus to support the development of uterine balloon tamponade devices conceived to stop post-partum haemorrhages (PPHs).

The phantom 3D model is generated by analysing the main requirements for validating uterine balloon tamponade devices. A modular approach is implemented to guarantee that the phantom allows testing these devices under multiple working conditions. Once finalised the design, the phantom effectiveness is validated experimentally.

The modular phantom allows performing the required measurements for testing the performance of devices designed to stop PPH.

PPH is the leading obstetric cause of maternal death worldwide, mainly in low- and middle-income countries. The proposed phantom could speed up and optimise the design and validation of devices for PPH treatment, reducing the maternal mortality ratio.

To the best of the authors’ knowledge, the 3D-printed phantom represents the first example of a modular, flexible and transparent uterus model. It can be used to validate and perform usability tests of medical devices.

This paper aims to propose a method to automate the tolerance analyses of mechanical assembly using STandard for the Exchange of Product model data-Application Protocol Part 242 (STEP AP 242) files derived from the 3-D computer-aided design (CAD) models.

Product manufacturing information and mating information available in ISO 10303 STEP AP242 files resulting from the 3-D CAD model of mechanical assembly are extracted. The extracted geometric attributes, geometric dimensioning and tolerancing (GD&T) and mating information are used to automatically generate assembly graph and mating edges required for the tolerance analyses of the mechanical assembly by using the matrix approach.

The feasibility of the proposed method is verified through two mechanical assembly case studies. The results of manual calculations and tolerance values computed by the automated method are very closely matching.

Tolerance analysis is an integral part of product development that directly influences the cost and performance of a product. Apart from the academic interest, the work is expected to have positive implications for the digital design and smart manufacturing industry that involve in the development of solutions for automation of design and manufacturing system functions.

The approach presented in the paper that aids the automation of tolerance analyses of mechanical assembly is an innovative application of the STEP AP 242 file. The automation of tolerance analyses would improve the productivity and efficiency of the product realization process.

The purpose of this paper is to focus on the finite element (FE) analyses undertaken for aerodynamically and structurally optimized design of a modern, lightweight civil unmanned air vehicle (UAV) made fully of composite materials.

The FE method has been applied to design and calculate the safety factors of all structural elements of the UAV. Fully parameterized design tools have been developed in the preliminary design phase, allowing automatic reshapes of the skin and the internal structural parts, wherever needed, to achieve optimal structural design, from the point of view of lightweight and structural integrity. Monotonic and fatigue tests have been performed on material specimens with various thicknesses and fibre textures, to verify the material properties used for the FE analyses. The load assumptions were in accordance with the valid international standards.

The material tests confirmed the validity of the material properties used within the FE calculations. The calculated safety factors were acceptable for all structural elements and components of the UAV. As a result, a lightweight, structurally optimized design has been achieved, considering the international, standardized specifications assumptions and fulfilling the safety requirements.

Design engineers may use the outcomes of this work as a guide to achieve optimal lightweight structures ensuring its operational strength using composite, lightweight materials.

A new, structurally optimized, lightweight aircraft design has been developed, able to accommodate heavy electronic payloads while being able to fly for over ten hours without refuelling. This medium altitude long endurance airplane can overview forests, seas and human trafficking autonomously and economically.

The aim of this paper is to present the main results of a research project finished in 2008 which concerned the selective laser melted (SLM) prototype of a new kind of minimally invasive resurfacing hip arthroplasty (RHA) endoprosthesis with the original multi‐spiked connecting scaffold (MSC‐Scaffold). Previous attempts performed in pre‐Direct Metal Manufacturing (DMM) era demonstrated that it was impossible to manufacture suitable prototypes of this RHA endoprosthesis (especially of the MSC‐Scaffold) using traditional machining technologies. Owing to an extensive development of DMM technologies observed in recent years the manufacturing of such prototypes has become possible.

Computer aided design models of pre‐prototypes and the prototype of the RHA endoprosthesis with MSC‐Scaffold were designed and initially optimized within the claims and the general assumptions of international patents by Rogala. Prototyping in SLM technology was subcontracted to SLM Tech Center (Paderborn, Germany). Macroscopic and SEM microscopic evaluation of the MSC‐Scaffold was performed using SLM manufactured prototypes and paying special attention to the quality and precision of manufacturing.

It was found that SLM can be successfully applied to manufacturing of prototypes of the original minimally invasive RHA endoprosthesis. The manufacturing quality of the 3D spikes system of the MSC‐Scaffold, which mimics the interdigitations of articular subchondral bone, has been proved to be geometrically corresponding to the biological original. Nevertheless, some pores and non‐melted zones were found in SLM prototyped RHA endoprosthesis cross‐sections which need to be eliminated to minimize the potential risk of clinical failure.

The presented case study was performed with a limited number of samples. More research needs to be performed on the rapid prototyped samples including microstructural and mechanical tests. The results may enable the optimization of the SLM manufacturing process of the prototypes of the minimally invasive RHA endoprosthesis with MSC‐Scaffold.

The SLM can be considered as potentially suitable for the fabrication of patient‐fitted minimally invasive RHA endoprostheses with MSC‐Scaffold.

For the first time, largely owing to SLM technology, it was possible to manufacture the prototype of the original minimally invasive RHA endoprosthesis with MSC‐Scaffold suitable for further research.

The purpose of this paper is to present the preliminary design of a medium altitude long endurance (MALE) unmanned aerial vehicle (UAV), focusing on the interaction between the aerodynamic and the structural design studies.

The classic layout theory was used, adjusted for the needs of unmanned aircraft, including aerodynamic calculations, presizing methods and CFD, to estimate key aerodynamic and stability coefficients. Considering the structural aspects, a combination of layout, finite element methods and custom parameterized design tools were used, allowing automatic reshapes of the skin and the internal structural parts, which are mainly made of composite materials. Interaction loops were defined between the aforementioned studies to optimize the performance of the aerial vehicle, maximize the aerodynamic efficiency and reduce the structural weight.

The complete design procedure of a UAV is shown, starting from the final stages of conceptual design, up to the point where the detail design and mechanical drawings initiated.

This paper presents a complete view of a design study of a MALE UAV, which was successfully constructed and flight-tested.

This study presents a complete, synergetic approach between the configuration layout, aerodynamic and structural aspects of a MALE UAV.