Abstract: Developing great products is not simple; users want products that can constantly adjust to their needs. The product development process should consider not only the users’ requirements and wishes but also their perceptions and emotions during and after the human-product interaction. Traditional studies have used self-report methods to study the users’ emotions; however, technological advances are making other methods able to measure respondents’ behavior. Electroencephalography (EEG), a technique for recording and interpreting the brain’s electrical activity, is becoming a valid tool to assess users’ emotional states. This study aims to explore the EEG as a method to interpret emotions. To do this, we created three different VR scenarios characterized by different interior design and automatic chromatic variations as a stimulus; this research aims to analyze if the changes in colors and scenarios reflect on the participants’ emotional responses, specifically on Valence, Arousal, and Engagement. The findings show that EEG results are a valid aid to emotion interpretation; also that color variation might influence users’ emotions and that the emotional responses were more evident when changing between scenarios. We expect this study can provide more information regarding the potential of physiological methods to explore users’ emotions during the product design and development.

Keywords: EEG | Emotional design | Engagement | Product development

Abstract: The evaluation of hip implantation success remains one of the most relevant problems in orthopaedics. There are several factors that can cause its failure, e.g.: aseptic loosening and dislocations of the prosthetic joint due to implant impingement. Following a total hip arthroplasty, it is fundamental that the orthopaedist can evaluate which may be the possible risk factors that would lead to dislocation, or in the worst cases, to implant failure. A procedure has been carried out with the aim of evaluating the Range of Movement (ROM) of the implanted prosthesis, to predict whether the inserted implant is correctly positioned or will be prone to dislocation or material wear due to the malposition of its components. Leveraging on a previous patented methodology that consists in the 3D reconstruction and movement simulation of the hip joint, this work aims to provide a more effective visualization of the simulation results through Mixed Reality (MR). The use of MR for the representation of hip kinematics and implant position can provide the orthopaedic surgeon with a deeper understanding of the orientation and position of implanted components, as well as the consequences of such placements while looking directly at the patient. To this end, an anchoring system based on a body-tracking recognition library was developed, so that both completely automatic and human-assisted options are available without additional markers or sensors. An Augmented Reality (AR) prototype has been developed in Unity 3D and used on HoloLens 2, integrating the implemented human-assisted anchoring system option.

Keywords: Computer-aided surgery | HoloLens 2 | Mixed reality | THA assessment | Total hip arthroplasty

Abstract: This chapter is focused on the main differences between the ISO and ASME standards in the geometrical specification domain of the industrial products, and it starts with details on the historical evolution of the two standards. The main principles of the ISO GPS and ASME GD&T standards, such as the principle of independence and the envelope requirement, are illustrated. Designers are recommended to always indicate the reference standard in the technical drawings of companies, as the interpretation of drawing specifications and the relative inspection may lead to two different results. Finally, the main novelties of the new ASME Y14.5:2018 standard and the new ISO 22081 standard on general tolerances are shown.

Abstract: The main concepts proposed in this chapter have the aim of expressing the fundamental rules on which the geometrical specification of workpieces can be based through a global approach that includes all the geometrical tools needed for GPS. Indeed, in an increased globalisation market environment, the exchange of technical product information and the need to unambiguously express the geometry of mechanical workpieces, are of great importance. The symbols, terms, and rules of the GPS language that are given in the ISO 17450, ISO 1101 and ISO 14660 standards are presented in this chapter through tools and concepts that allow an engineer to perfectly specify the imperfect geometry of a component, and to understand the impact of the drawing specifications on inspection.

Abstract: The advantages of the geometric specification of a product are here illustrated by converting a traditional 2D coordinate tolerancing drawing using the geometrical tolerance method. The new language of symbols permits the functional requirements of the products to be fully expressed in technical documentation. Moreover the dimensioning of a workpiece according to the geometrical tolerance method can reduce the ambiguity in the indications and in the interpretation of the dimensional and geometrical requirements of the products in order to achieve not only unambiguous communication between the design, production and quality control entities, but also with the clients and suppliers of the outsourced processes.

Abstract: In the absence of other indications, all the specified dimensions and tolerances are applied and controlled without the action of any force, except gravity, but components such as thin metal and flexible parts, rubber gaskets, and flexible parts in general, can deform or bend, even as just a result of their weight. These components should be inspected under a restrained condition in order to simulate their shape in the installed condition. The restraint or force on the non-rigid parts is usually applied in such a manner as to resemble or approximate the functional or mating requirements. According to the ISO standards, the non-rigid parts should be identified on a drawing by means of “ISO 10579-NR” (Non Rigid) obligatory indications within or near the title block; such a note indicates that the part is not considered rigid and it indicates the clamping forces or other requirements necessary to simulate the assembly conditions. In order to invoke a restrained condition in the ASME standards, a general note, or a local note, should be specified or referenced on the drawing to define the restraint requirements. When a general note invokes a restrained condition, all the dimensions and tolerances apply in the restrained condition, unless they are overridden by a “free state” Ⓕ symbol

Abstract: A geometrical tolerance on a profile is one of the most versatile and powerful instruments that can be used for functional dimensioning, and is the tolerance most frequently used by designers. A profile may in fact be used to control the size, form, orientation and location of a feature. Because of the flexibility in the level of control that can be achieved with the profile tolerance, this control may be used to substitute the classical coordinate dimensioning method. The present chapter covers the ISO rules on profile tolerances in order to appropriately specify the control of a profile with a combination of the SZ, CZ, UF symbols and the bidirectional and unidirectional zones that are specified with profile tolerances. A composite profile tolerance is used in the ASME standards when the design applications require stricter tolerances on the form than is needed for the orientation or location of the same feature. The new ASME symbols, that is, From-To and dynamic profile, are presented.

Abstract: This chapter describes how to use location tolerances to specify an allowable location error. The location tolerances that should be used, in function of the feature of the workpiece that has to be located, are in particular presented. The effects of the material condition requirement and the correct choice of the modifiers for position tolerances (axis and surface interpretation) are illustrated. Particular emphasis is given to the location of the patterns, as introduced with the new rules of the ISO 5458:2018 standard (multiple indicator pattern specification and simultaneous requirement). When geometrical position tolerances are applied, the value of the tolerance is calculated from the mating conditions (fixed and floating fastener conditions). The ASME standards specify, without any shadow of doubt, that the position tolerance symbol should only be utilised for a “feature of size”, while the ISO standards allow it to be used to position a planar surface. The ISO standards are defined as “CMM Friendly”, that is, the preferred control system is the coordinate measurement machine, while the ASME standards are based on functional gauges that represent a physical representation of the tolerance zone. A special functional application of location tolerances is to control concentricity and symmetry. These controls have been removed from the new ASME standard.

Abstract: In the past, the verification of the local size of workpieces was carried out using traditional metrological instruments, such as callipers and micrometres, or using hard gauges to check for conformance with the global size tolerances. Today, in order to remove any ambiguities that existed in the traditional size tolerance specifications, it is necessary to both exploit the benefits of CMMs and other coordinate measuring systems that collect several points from the surface of a feature and, at the same time, to expand the concept of size tolerancing in order to communicate the function of a part more clearly. The specification operators defined in the ISO 14405 standards provide mechanisms that can be used to expand the domain of size specifications by means of a rich, new set of size modifiers, which provide new capabilities that can be used to address the requirements that arise from many industrial applications.

Abstract: A datum system has the purpose of defining a set of two or more ideal features established in a specific order (for example, a system made up of a triad of mutually orthogonal planes) that allows not only the tolerance zones to be orientated and located, but also their origin to be defined for the measurement, and the workpiece to be blocked during the control. When it is not desirable to use a complete integral feature to establish a datum feature, it is possible to indicate portions of the single feature (areas, lines or points) and their dimensions and locations using datum targets. This chapter illustrates the main differences between the ISO 5459 and ASME standards for the specification of datums and highlight some theoretical and mathematical concepts. This section also provides simple rules to follow whenever choosing functional datums to ensure the part will function as intended, with the least possible amount of variation.

Abstract: The technical product documentation that is currently drawn up in many companies is unfortunately still ambiguous and contains many errors, such as erroneous datums, imprecise or missing distances, as well as incongruent and difficult to check tolerances. For about 150 years, a tolerancing approach called “coordinate tolerancing” was the predominant tolerancing system used on engineering drawings. This methodology in fact no longer results to be the most suitable for the requirements of the modern global productive realty, in which companies, for both strategic and market reasons, frequently resort to suppliers and producers located in different countries, and it is therefore necessary to make use of communication means in which the transfer of information is both univocal and rigorous. GD&T or GPS is a symbolic language that is used to specify the limits of imperfection that can be tolerated in order to guarantee a correct assembly, as well as the univocal and repeatable functionality and control of the parts that have to be produced.

Abstract: It is possible to control four form tolerance types: straightness, flatness, roundness and cylindricity. The chapter covers all the concepts necessary to define specification operators (according to ISO 17450-2) and some procedures to establish the reference elements in order to define the deviation errors. Some terms related to form parameters are described such as peak-to-valley, peak-to-reference and reference-to-valley deviations. The ASME standards use the envelope requirements or Rule #1, according to which form tolerances are contained within the dimensional ones, and these tolerances are therefore only used with the purpose of limiting the error when the workpiece is produced with dimensions close to the least material condition.

Abstract: A run-out error is the surface variation that occurs relative to a rotation axis. There are two types of run-out controls: circular run-out (2D) and total run-out (3D). Run-out tolerances are composite controls that define the requirements for the permissible coaxiality, orientation and form deviations of a surface element in relation to a datum axis. The application of the run-out control to an assembly and its combination with the tangent plane symbol, are illustrated in this chapter as main novelties of the new ASME Y14.5-2018 standard.

Abstract: Orientation tolerances (parallelism, perpendicularity and angularity) are used to control the orientation of a feature (surface or feature of size) with respect to one or more datums. When the orientation tolerances are applied to a feature of size and an MMR or LMR is added, the control of the orientation deviation no longer refers to the median line, but to the entire extracted feature (MMVC boundary), and it should not violate the MMVC virtual condition. The ISO and ASME standards use two different approaches to control the orientation of a feature of size: in order to orient a feature of size, the ISO standards define the concept of extracted median line or median surface. Instead, in the ASME standards, the axis or median plane is used to control the orientation of a feature of size.

Abstract: In ISO GPS terminology, the maximum material requirement, (MMR) and least material requirement (LMR) represent two of the fundamental rules on which geometrical dimensioning with tolerances is based, and which are the subject of the ISO 2692 standard. The designer, when establishing a maximum or least material requirement, defines a geometrical feature of the same type and of perfect form, which limits the real feature on the outside of or inside the material. MMR is used to control the assemblability of a workpiece while LMR is used to control a minimum distance or a minimum wall thickness. This chapter also introduces the Reciprocity requirement (RPR) and the “zero tolerance” concepts and offers practical examples to guide a designer in his/her choice of the correct requirement from the geometrical tolerance specifications.

Abstract: Three dimensional face analysis is being widely investigated since it appears as a robust solution to overcome the limits of two dimensional technologies. 3D methods allow to relate the recognition process on features not depending on lightning, head poses, make up and occlusions. This paper proposes a new approach to the problem consisting of a novel image representation, where specific facial descriptors replace the RGB traditional channels and a convolutional neural network performs the classification. We chose to use MobileNetV2, a relatively new network, as it has a low amount of parameters to train. The method has been evaluated on the Bosphorus database, and even though it is still a preliminary study, the results obtained with our method are extremely encouraging; the recognition rate achieved is 97.560% and it is comparable to the state of the art. This result, reached despite the fact that the Bosphorus database has a great number of subjects (105) but a low number of scans (4666), shows the effectiveness of this representation combined with convolutional neural networks.

Keywords: 3D face recognition | Curvedness | Deep Convolutional Neural Network | MobileNetV2 | Shape index

Abstract: This study proposes a novel occlusions detection and restoration strategy. The aim is to success with 3D face recognition even when faces are partially occluded by external objects. The method, which relies on geometrical facial properties, is designed for managing two types of facial occlusions (eye and mouth occlusions due to hands). First occlusions are detected and (if present) classified, by considering their effects on the 3D points cloud. Then, the occluded regions are progressively removed, and finally, the non-occluded symmetrical regions are used to restore the missing information. After the restoration process, face recognition is performed relying on the restored facial information and on the localized landmarks. The landmarking methodology relies on derivatives and on 12 differential geometry descriptors. The discriminating features adopted for facial comparison include shape index histograms, Euclidean and geodetical distances between landmarks, facial curves, and nose volume. Obtained recognition rates, evaluated on the whole Bosphorus database and on our private dataset, ranging from 92.55 to 97.20% depending on the completeness of data.

Keywords: 3D face | Differential geometry | Face analysis | Face recognition | Feature extraction

Abstract: The present work deals with the best method and tool design for chopping hazelnut kernels. The requested final product must have a standard appearance both in size and shape. This is not easy to be achieved. A geometrical study using 3D models—both for kernel and cutting tools—simulates the industrial process and forecasts shape and size distribution of the final product. Final comparison between 3D simulation and experimental results shows an acceptable agreement. A simplified and symmetrical geometry is discussed in the present paper. Work is in progress and further and more complete results are expected, but the method of 3D simulation proved to be very useful.

Abstract: Surgical interventions for jaw reconstruction require the design and the production of surgical guides that allow the surgeon to operate quickly and accurately. In some cases, the reconstruction is performed by inserting a prothesis, thus operating exclusively on the jaw, while in other cases the reconstruction is performed by withdrawing and inserting part of the fibula in place of the original jaw bone. This project aims to develop a procedure that allows 3D modeling of the surgical guides necessary for surgical intervention. The idea is to find a surgical guide archetype, a starting shape for the surgeon so that the cutting planes can be oriented without the surgical guide having to be redesigned from scratch for every single patient. The first step of the procedure is the segmentation, performed applying the thresholding operation on the images provided by magnetic resonance MR in order to identify the region of interest (ROI). The second step is the reconstruction of the 3D model, so that a mesh is obtained from 2D images. Subsequently the mesh is post-processed and the cutting plans along which the surgeon will intervene are defined.

Keywords: 3D modeling | 3D reconstruction | Maxillofacial surgery | Surgical guides

Abstract: This paper deals with parenthood perception (maternal and paternal) after the visualization and interaction (touch) with a 3D printed facial fetal model. The model is created using Additive Manufacturing techniques, starting from the image elaboration of routine ultrasound data. In this study, the method used for the elaboration and construction of 3D printable models of fetal faces starting from routine ultrasound images is briefly described. In addition, we present the results of a new survey conducted with future parents at the Altamedica clinic (Rome, Italy) to verify whether there are any benefits derived from the use of 3D printing models with future parents, both regarding the improvement of the parenthood experience, and the improvement of the understanding and collaboration with the physicians in case of fetal malformations, using 3D models coupled with the data of routine ultrasound examinations.

Keywords: 3D ultrasound | Additive manufacturing | Fetal face | Image processing | Parenthood perception | Survey

Abstract: This work proposes a method for recognizing the main 13 Facial Action Units and the 6 basic emotions. The methodologies rely on Differential Geometry to extract relevant discriminant features from the query faces, and on some linear quantities used as measures: Euclidean, geodesic, and angles between 17 automatically extracted soft-tissue landmarks. A thresholding system which evaluates local properties of connected regions, selected through tailored geometrical descriptors, supports the identification of the AUs. Then, a technique based on crisp logic allows the identification of the global expression. The three-dimensional context has been preferred due to its invariance to different lightening/make-up/camouflage conditions.

Keywords: Emotional design | Face expression recognition | Intelligent drive

Abstract: Methodologies for 3D face recognition which work in the presence of occlusions are core for the current needs in the field of identification of suspects, as criminals try to take advantage of the weaknesses among the implemented security systems by camouflaging themselves and occluding their face with eyeglasses, hair, hands, or covering their face with scarves and hats. Recent occlusion detection and restoration strategies for recognition purposes of 3D partially occluded faces with unforeseen objects are here presented in a literature review. The research community has worked on face recognition systems under controlled environments, but uncontrolled conditions have been investigated in a lesser extent. The paper details the experiments and databases used to handle the problem of occlusion and the results obtained by different authors. Lastly, a comparison of various techniques is presented and some conclusions are drawn referring to the best outcomes.

Keywords: 3D face analysis | Face detection | Face recognition | Facial occlusions | Facial restoration

Abstract: This study proposes a novel automatic method for facial landmark localization relying on geometrical properties of 3D facial surface working both on complete faces displaying different emotions and in presence of occlusions. In particular, 12 descriptors coming from Differential Geometry including the coefficients of the fundamental forms, Gaussian, mean, principal curvatures, shape index and curvedness are extracted as facial features and their local geometric properties are exploited to localize 13 soft-tissue landmarks from eye and nose areas. The method is deterministic and is backboned by a thresholding technique designed by studying the behaviour of each geometrical descriptor in correspondence to the locus of each landmark. Occlusions are managed by a detection algorithm based on geometrical properties which allows to proceed with the landmark localization avoiding the covered areas. Experimentations were carried out on 3132 faces of the Bosphorus database and of a 230-sized internal database, including expressive and occluded ones (mouth, eye, and eyeglasses occlusions), obtaining 4.75 mm mean localization error.

Keywords: 3D face | Differential geometry | Face analysis | Feature extraction | Landmark localization

Abstract: This work proposes a methodology to automatically diagnose and formalize prenatal cleft lip with representative key points and identify the type of defect (unilateral, bilateral, right, or left) in three-dimensional ultrasonography (3D US). Differential Geometry has been used as a framework for describing facial shapes and curvatures. Then, descriptors coming from this field are employed for identifying the typical key points of the defect and its dimensions. The descriptive accurateness of these descriptors has allowed us to automatically extract reference points, quantitative distances, labial profiles, and to provide information about facial asymmetry. Seventeen foetal faces, nine of healthy foetuses and eight with different types of cleft lips, have been obtained through a Voluson system and used for testing the algorithm. In case no defect is present, the algorithm detects thirteen standard facial soft-tissue landmarks. This would help ultrasonographists and future mothers in identifying the most salient points of the forthcoming baby. This algorithm has been designed to support practitioners in identifying and classifying cleft lips. The gained results have shown that differential geometry may be a valuable tool for describing faces and for diagnosis.

Keywords: 3D ultrasound | Cleft lip | Dysmorphisms | Landmarking | Syndrome diagnosis

Abstract: 3D face was recently investigated for various applications, including biometrics and diagnosis. Describing facial surface, i.e. how it bends and which kinds of patches is composed by, is the aim of studies in Face Analysis, whose ultimate goal is to identify which features could be extracted from three-dimensional faces depending on the application. In this study, we propose 54 novel geometrical descriptors for Face Analysis. They are generated by composing primary geometrical descriptors such as mean, Gaussian, principal curvatures, shape index, curvedness, and the coefficients of the fundamental forms. The new descriptors were mapped on 217 facial depth maps and analysed in terms of descriptiveness of facial shape and exploitability for localizing landmark points. Automatic landmark extraction stands as the final aim of this analysis. Results showed that the newly generated descriptors are suitable to 3D face description and to support landmark localization procedures.

Keywords: 3D Face | Face Analysis | Face Recognition | Geometry | Landmarks

Abstract: Indirect estimation of the stiffening effect caused by the fitting process of an automotive wheel is hereby presented to detect optimal interference of automotive steel wheels. The effects are related to components and assembly characteristics, such as masses and natural frequencies. Both the components of the wheel, which are disc and rim, are subject to generalised tolerances and uncertainties, mainly related to elasto-plastic material properties, dimensional and geometrical tolerances and manufacturing process parameters. Taking into account the theoretical change in the dynamic properties of a pre-stressed structure with respect to its non-stressed condition, the stiffening effect caused by the fitting process is expected to bring consequences on the natural frequencies of particular and representative modes of the assembly. Moreover, the dynamic behaviour of the assembly can be related to the one of the two separate components, in order to improve the indirect estimation of the pre-stressed condition. The methodology is developed starting from numerical and experimental modal analysis, building a meta-model based on these training data, then evaluating the performance of that on a production wheel case. The optimal interference fit estimations are tested on a standard steel wheel for the Iveco Ducato commercial vehicle. Then to evaluate the robustness of the method, the meta-model is used for a compact spare tyre of a saloon car.

Keywords: Automotive wheels | Dimensional and geometrical tolerances | Experimental modal analysis | Finite element method | Interference fit

Abstract: A family of parametric 3D CAD models based on stochastic distribution of not-engineering real life object has been studied. The subject considered was the Tonda Gentile Trilobata (TGT) hazelnut variety, which is the most important variety in the Langhe region in Piedmont, Italy. The aim was to obtain a master model which measured, or stochastically-obtained, values of parameters given as input, to generate a number of samples which have the same statistical distributions of the real world ones. These generated models could then be used in virtual simulations of machinery and equipment used by industries to process the hazelnut, making possible studies of modifications to improve the production process performance. A single parametric CAD model was considered with respect to several scanned models from real hazelnuts, with the possibility of generating families of solutions suitable for the simulation aims. The work was carried out in steps of increasing complexity checking accuracy using different types of comparisons to validate the different models.

Keywords: Dried fruits | Feature-based modelling | Reverse engineering

Abstract: A 3D automatic facial expression recognition procedure is presented in this work. The method is based on point-by-point mapping of seventeen Differential Geometry descriptors onto the probe facial depth map, which is then partitioned into seventy-nine regions. Then, features such as mean, median, mode, volumes, histograms are computed for each region and for each descriptor, to reach a varied large set of parameters representing the query face. Each set of parameters, given by a geometrical descriptor, a region, and a feature, form a trio, whose featuring numerical values are compared with appropriate thresholds, set via experimentation in a previous phase by processing a limited portion of the public facial Bosphorus database. This allows the identification of the emotion-based expression of the query 3D face among the six basic ones (anger, disgust, fear, joy, sadness, surprise). The algorithm was tested on the Bosphorus database and is suitable for applications in security, marketing, medical. The three-dimensional context has been preferred due to its invariance to different lightening/make-up/camouflage conditions.

Keywords: 3D face | Differential geometry | Emotions | Face expression recognition (FER) | Facial expression recognition | Shape index

Abstract: This study proposes a novel approach to automatically localise 11 landmarks from facial RGB images. The novelty of this method relies on the application, i.e., point-by-point mapping, of 11 differential geometry descriptors such as curvatures to the three individual RGB image components. Thus, three-dimensional features are applied to bidimensional facial image representations and used, via thresholding techniques, to extract the landmark positions. The method was tested on the Bosphorus database and showed global average errors lower than five millimetres. The idea behind this approach is to embed this methodology in state-of-the-art 3D landmark detection methods to accomplish a full automatic landmarking by exploiting the advantages of both 2D and 3D data. Some landmarks such as pupils are arduous to be automatically extracted only via three-dimensional techniques. Thus, this method is intended as a bridging-the-gap preliminary technique that takes advantages of 2D imaging only for integrating advanced landmark localisation methodologies.

Keywords: Differential geometry | Face analysis | Facial landmarks | Landmark localisation | RGB images

Abstract: Recent Face Analysis advances have focused the attention on studying and formalizing 3D facial shape. Landmarks, i.e. typical points of the face, are perfectly suited to the purpose, as their position on visage shape allows to build up a map of each human being’s appearance. This turns to be extremely useful for a large variety of fields and related applications. In particular, the forensic context is taken into consideration in this study. This work is intended as a survey of current research advances in forensic science involving 3D facial landmarks. In particular, by selecting recent scientific contributions in this field, a literature review is proposed for in-depth analyzing which landmarks are adopted, and how, in this discipline. The main outcome concerns the identification of a leading research branch, which is landmark-based facial reconstruction from skull. The choice of selecting 3D contributions is driven by the idea that the most innovative Face Analysis research trends work on three-dimensional data, such as depth maps and meshes, with three-dimensional software and tools. The third dimension improves the accurateness and is robust to colour and lightning variations.

Keywords: 3D face | Fiducial point | Forensic | Landmarks | Reconstruction

Abstract: Traditionally, the development of complex mechatronic products, such as products in aerospace or automotive domain, have employed a "document-based" Systems Engineering (SE) approach to perform the systems engineering activities. This approach is characterized by the generation of textual specifications and design documents that are used and exchanged between all project users. Today, innovative interdisciplinary product development requires a rethinking of current methods and IT solutions, employing an efficient Systems Engineering strategy. The goal is to move from a "documentbased" approach to a "model-based" approach that addresses all engineering disciplines. The "Model Based Systems Engineering (MBSE)" methodology is an approach that involves modeling for supporting system requirements definition and management, design, analysis, verification and validation activities. This approach provides a set of data and models that allows design teams to analyze the performances of the different product configurations in an early stage and to ensure product data traceability along the entire product lifecycle maintaining a structured relation between costumer requirements and all the product solution analyzed. At present a shared operative approached aimed at integrating MBSE in a Product Life Cycle Management scenario doesn't exist. For that reason, the paper outlines the key activities to deploy successfully a MBSE methodology, based on the Systems Modeling Language (SysML) within a PLM platform by the use of the Product Functional View.

Keywords: Model-Based Systems Engineering | Product Lifecycle Management | SysML | Systems engineering

Abstract: Powering a remote wireless sensor is a challenging task if batteries are not suitable or enough capacious and their substitution is not feasible. In this project a remote wireless sensor is placed inside training shoes with the aim to collect and transmit data to evaluate and track the performance of an athlete. The primary energy source is the impact between the shoe and the ground while walking or running. The harvester has been designed by means of a multi-physics optimization based on an integrated electromagnetic-mechanical-electric-electronic simulator. Thus an automated optimization of the device with respect to volume constraints, magnets dimensions, induction coils placement and sizes and electric/electronic coupling have been performed to increase the average power extracted from the device at different speeds. These parameters are used as starting point for the product development phase in order to obtain a consistent number of prototypes and validate the simulations on these physical demonstrators. Finally, experimental outcomes evince the expected performance and a more than satisfactory agreement with the models, confirming the feasibility of the application.

Keywords: Design and optimization | Magneto-mechanical generator | Product development experimental application | Shoe mounted device

Abstract: In order to improve the performance of shelling machines, and to enhance the numerical modelling of anisotropic behaviour of hazelnuts shells, the mechanical properties of shells are useful experimental data. A procedure to obtain an effective numerical model and to calibrate anisotropic material properties by means of experimental testing is described. The procedure was applied to a commercial variety of Italian hazelnuts and the mechanical properties were experimentally obtained for shell on specimens obtained from conform hazelnuts. The numerical finite element model investigates single and double curvature geometry simulation performance of the shell specimens.

Keywords: Anisotropic material properties | FEM | Hazelnut shells | Three point bending test

Abstract: This article presents a methodology for the treatment of uncertainty in nonlinear, interference-fit, stress analysis problems arising from manufacturing tolerances. Image decomposition is applied to the uncertain stress field to produce a small number of shape descriptors that allow for variability in the location of high-stress points when geometric parameters (dimensions) are changed within tolerance ranges. A meta-model, in this case based on the polynomial chaos expansion, is trained using a full finite element model to provide a mapping from input geometric parameters to output shape descriptors. Global sensitivity analysis using Sobol's indices provides a design tool that enables the influence of each input parameter on the observed variances of the outputs to be quantified. The methodology is illustrated by a simplified practical design problem in the manufacture of automotive wheels.

Keywords: Dimensional tolerances | Global sensitivity analysis | Interference fit | Polynomial chaos expansion | Shape descriptor

Abstract: The next generation of tyre sensors will be bonded directly onto the inner liner (IL) in order to measure important parameters such as strain, vehicle load, contact pressure, the tyre-road friction coefficient or wear. Sensor packages (SP) have a sensor node, which is bonded and kept in position by a specifically designed rubber housing (RH). Since the measurements they provide to the car control unit are used to improve the active or passive safety of vehicles, these packages can be considered critical safety components that should be dimensioned carefully. A tyre analysis, whether statical or dynamical, in which the complete structure is considered, under any load, inflating pressure or temperature working condition is mainly oriented towards defining the tyre product. The insertion of an SP inside such a complex tyre model, with the purpose of only analysing its behaviour, would be too time consuming considering the strong nonlinear behaviour of the tyre model. Therefore, this work presents a method that can be used to define a computationally lightweight finite element method (FEM) simulation, which is able to recreate the working conditions to which an SP is subjected. The basic idea behind this method is to separate the analysis of the SP from the structural tyre analyses; the latter is only run once, independently. The first task is to impose the deformed shape on a simplified model of the tyre with a bonded SP. All the deformation states that occur during rolling are computed in a static FEM simulation. The second task is to apply the inertial forces that act on the SP, whether computed or measured directly on the tyre, as external loads. These tasks are implemented in user-defined routines that are executed by the FEM solver. The method permits the stress concentration inside the RH material volume to be identified, at any angular position of the wheel. This information is then used, during the design process, to identify the most suitable geometry to level out the stress distribution. The resulting shape can be tested under different boundary conditions, by substituting the corresponding data arrays, but using the same FEM model. Since the deformed shapes and inertial forces are stored as simple text matrices (which are also used to form a test library), they can be easily interchanged in a flexible way. This more extended design process can reduce the costs of prototyping moulds. The proposed methodology has been developed and tested for the Pirelli Cyber TM Tyre project.

Keywords: FEM | Rubber house | Tyre sensor

Abstract: A strong integration between different design tools is desirable to improve the work of engineers, reducing the number of errors and speeding up the design process. In this article, the authors present a strong integration between three-dimensional computer-aided design models and multidomain simulation applied to the design of a magnetomechanical energy harvester. A MATLAB framework controls a block-oriented Simulink model, drives the Finite Element Method Magnetic simulation and manages the updating of the Solid Works computer-aided design models of the device. The parameters involved in the different simulations and in the computer-aided design models are stored in a unique data file. Moreover, constructive drawings are automatically updated and are immediately suitable for tolerance and design constraint checks and also for the effective prototyping of the device. Constructed prototypes are immediately suitable to validate the performance predicted by the model.

Keywords: Computer-aided design-computer-aided engineering integration | Energy Scavenging | Multidomain simulation | Virtual prototyping

Abstract: Nowadays, manufacturing industries have to shorten the time to market in order to satisfy needs of customers and to survive in global competitive markets. For these reasons a new type of product data development and management is necessary. The Product Lifecycle Management (PLM) is an emerging philosophy to improve strategic engineering for managing information, processes and resources to support the life cycle of a product, from its conception, development, launch and the withdrawal. The well-established technologies CAD / CAE / CAM are fundamental part of it, although their interactions may be only partially involved. The paper takes into account open questions regarding the relationship between models and simulations and new possible scenarios related to their integration starting from a complete and multi-disciplinary case-test involving the virtual-experimental deliverable process of the fatigue life prediction and related structural modification design applied to a suspension cab for truck vehicle. © 2013 Springer-Verlag France.

Keywords: CAD / CAE integration | Experimental measurements | Parametric design | Product Lifecycle Management

Abstract: In this paper experimental investigations of interference fit effects on the dynamic behaviour of assembled wheels are provided. The performed analyses on the automotive components take into account manufacturing pre-stresses and dimensional tolerances of mating parts. Experimental modal analysis is made on a set of components with identical nominal values to prove either the component or the assembly variability. For each mode a PCE-based meta model is developed upon a small sample of experimental observations and the interference fit level is estimated by means of the stress stiffening effect. The presented technique is aimed at improving the design and development of industrial components through the combination of established methodologies. The effectiveness of modal analysis, when combined with numerical/statistical approaches is pointed out.

Keywords: Design for modal assembly | Dimensional tolerances | Experimental modal analysis | PCE meta-models | Stress stiffening effect

Abstract: The dynamic properties of crossing and veering in coupled structures have been studied both numerically and analytically, but they are difficult to investigate using Finite Element Analysis because of the change in the topological arrangement due to the different configuration. Isogeometric Analysis, recently developed method for numerical simulation, could overcome some of the drawbacks of the change in the configuration such as remeshing, coupling between the nodes of the different models, need of a fine mesh to allow small change in the configuration to be comparable to the mesh size. The key of this method is to avoid meshing and using the same basis functions used by the geometry, namely Non-Uniform Rational B-Splines (NURBS), to define the discretization of a Finite Element model. Other advantages are the possibility of increasing the order of the functions to obtain smooth stress field across the element interfaces. An experimental test-rig composed by beams and masses, which allow different configuration and dynamic coupling as well, is used as test case to validate the accuracy of the results with respect to both experimental data and classical Finite Element Analysis.

Keywords: Crossing and veering phenomena | Isogeometric analysis | Modal analysis of coupled structure | Nitsche’s method

Abstract: Purpose - Supplying remote wireless sensors is not an easy task if the site where the device is located is not easily accessible. In order to obtain direct measurements of the road-vehicle interactions, sensors must be placed inside the tyre environment thus a power supply must be available for their working there without any wire connection with the car main power. The paper aims to discuss these issues. Design/methodology/approach - An electro-mechanical energy harvester has thus been developed for supplying an automotive wireless sensor of pressure, temperature and acceleration to be placed on the inner line of a tyre. The primary energy source is the vibrations or variable accelerations imposed to the device and induced in the tyre by the wheeling. Findings - The harvester has been designed by means of a multi-physics optimisation based on an integrated electromagnetic-mechanical circuit simulator. Thus an automated optimisation of the device with respect to volume constraints, magnets dimensions, induction coils placement and size have been performed to increase the average power extracted from the device at different wheeling speeds. Originality/value - The use of the multi-physics environment together with automated optimisation technique has been tested for the first time on the electromagnetic harvester structure.

Keywords: Applied electromagnetism | Energy harvesting | Multiphysics | Optimal design

Abstract: The adhesive bonding technology can be used in combination with other traditional joining methods, such as mechanical fastening techniques (e.g. rivets or bolts) or welding techniques, generating a hybrid joint. Hybrid adhesive joints are designed to exploit the advantages of the different techniques and, if possible, overcome their drawbacks. This study focuses on the interference fitted/adhesive bonded joining technique. This method consists in two cylindrical components coupled together by inserting one into the other, after having placed an adhesive on the mating surfaces. This hybrid joint, generally realized by exploiting acrylic anaerobic systems, has been studied to evaluate the interaction between the tensile field of the components (at the interference level) and the adhesive strength under both static and dynamic loading conditions. Notwithstanding this, the contributions of the adhesive and the interference on the performance of the final joint are still not completely clear. The aim of this research is then to further study the factors affecting the resistance of this hybrid joint. Hub-shaft samples, joined by means of a press fit, were tested under an axial push out load. Hybrid joints were compared to both adhesive joints in clearance conditions and interference joints. In particular, different levels of interference were analyzed in order to clarify the role played by the tensile field between the hub and the shaft, and the influence of the friction effects between them. Numerical simulations were also employed to support the experimental data in the evaluation of the behavior of the adhesive and its relation with all the phenomena influencing the hybrid system. It was found that tribological phenomena played an important role in governing the mechanical behavior of the unbonded samples, while they can be considered negligible in presence of the adhesive. The correlation between bonded and unbonded press-fitted joints was investigated pointing out that the maximum strength of the hybrid joint is mainly related to the resistance of the epoxy adhesive. © 2014 Elsevier Ltd.

Keywords: Finite elements | Hybrid interface | Interference fit | Joint design | Mechanical properties of adhesives

Abstract: Powering a remote wireless sensor is a challenging task if batteries are not suitable or enough capacious and their substitution is not feasible. A remote wireless sensor can be placed inside a shoe with the aim to collect and transmit data to evaluate and track the performance of an athlete. The primary energy source is the impact between the shoes and the ground while walking or running. The harvester has been designed by means of a multi-physics optimization based on an integrated electromagnetic-mechanical simulator. Thus an automated optimization of the device with respect to volume constraints, magnets dimensions, induction coils placement and size have been performed to increase the average power extracted from the device at different walking speeds. Finally, prototypes of the optimal configurations demonstrate the predicted performance and a more than satisfactory agreement is evinced. © The Society for Experimental Mechanics, Inc. 2013.

Keywords: Electromagnetic generator | Energy scavenger | Magneto-mechanical | Optimization | Shoe mounted device

Abstract: This paper presents the application of semi-active control for optimising the power harvested by an electro-mechanical energy harvester. A time-periodic damper, defined by a Fourier series, is introduced for energy harvesting in order to increase the performance of the device. An analytical solution for the transmissibility and the average absorbed power is derived based on the method of harmonic balance. The coefficients of the semi-active model are optimised to maximise the harvested power. The harvested power from the optimum periodic time-varying damper at a particular frequency is compared and is shown to be greater than that from an optimum passive damper and a semi-active on-off damper not only at that particular frequency but also at other frequencies. In addition, the performance of the optimised periodic time-varying damper is also compared with an arbitrary semi-active time-periodic damper, which has the same transmissibility at resonance. An optimisation is carried out to maximise the power in a frequency range and the optimum damper is derived as a function of the excitation frequency. The numerical results are validated with the analytical approach. © 2013 Elsevier Ltd.

Abstract: In the automotive industry a significant part of research is dedicated to design and produce better products. The unavoidable presence of uncertainties in manufacturing processes and structural parameters leads to the necessity to develop stochastic models able to correctly represent physical behaviours. This paper presents numerical and experimental investigations on the effects of the fitting process on the stress/strain map of assembled automotive rim-disk systems. Different strategies of geometrical decomposition are used to condense large volumes of data by retaining essential information for the whole design process including not only manufacturing pre-stresses and operational loads but also dimensional tolerances of mating parts by means of a probabilistic model. Efficient approaches are used to identify the relative importance of input factors on the output uncertainties. A real test case of a wheel assembly is presented and discussed. Copyright © 2013, AIDIC Servizi S.r.l.

Abstract: This article presents multidisciplinary optimization methods applied to the design and performance evaluation of a magneto-mechanical energy scavenger for automotive wireless tire sensors. Optimal performance strictly depends on source characteristics, volume, weight and power density targets, energy scavenger typology, technological and manufacturing capabilities, optimization and reliability of performance, environment requirements, and so on. Thus an optimization study has been conducted on equivalent viscous damping due to strong magneto-electrical-mechanical coupling. To do this, an optimization tool has been developed that maximizes the power output in specific working conditions by varying the number and size of coils. © The Author(s) 2011.

Keywords: damping optimization | electromechanical device | energy harvester | nonlinear dynamic

Abstract: This article presents a very compact electromechanical wideband energy harvester optimized for tire applications. The device exploits an asymmetric magnetic spring to be adaptive and effective at almost any vehicle speed. The device has been simulated through an experimentally validated SIMULINK block-oriented model. The simulation takes into account nonlinear dynamic and adaptive resonant behavior of the seismic mass, electromagnetic, and magnetostatic coupling between floating magnetic mass and coils, and the transfer of the generated power to an external load by means of a nonlinear circuit interface. A particular focus on the pneumatic effect on the floating magnet has been made. A convenient choice of clearance between moving and fixed parts can be used to create an effective air brake preventing or softening shocks with end stops and to modify system dynamic. A nonlinear equivalent spring dashpot model of the pneumatic effect and a method to estimate its parameters from geometry have been proposed. An analysis of different nonlinearities of the system at different vehicle speed and a study on the combined effect of softening and hardening behavior of the device have been performed and discussed. © SAGE Publications 2011.

Keywords: adaptive resonance | electromechanical device | energy scavenger | nonlinear dynamic

Abstract: This paper presents a multi-physic modeling of an electromechanical energy scavenging device able to supply energy inside car tires for wireless sensors. A permanent magnet, connected to the inner liner of a tire, is accelerated along a guide by the tire deformation during car motion; by interacting with coils it generates a power which is conditioned by a proper electronic interfaced to an external load. The original approach implemented in this kind of device is the nonlinear dynamic properties designed and controlled: adaptive resonance in function of car velocity is optimized for increasing its global efficiency. The energy conversion process takes into account the simulation of different phenomena such as: non linear dynamic and adaptive resonant behavior of the seismic mass, electromagnetic and magneto-static coupling between moving mass and coils, transfer of the generated power to an external load by means of a nonlinear circuit interface. An integrated model of the cascaded energy steps is developed inside the Simulink/Stateflow environment. A good agreement is found in the comparison between theoretical model and experiments conducted on prototypes produced by means of drawings directly obtained from 3D CAD models. To compare these results to other energy harvesting devices found in Literature, the same device adapted with symmetric configuration is derived. Empirical formulas to measure efficiency are evaluated for this device and compared with Literature results. The accurate modeling of the energy conversion device is a breakthrough in the modeling of these kinds of devices and allows to reach interesting power/volume ratios: small dimensions (about one cubic centimeter) and relatively high power output (more than one milliwatt). © 2011 SAE International.

Abstract: In the present paper, starting from a first attempt design of engine components, a CAD/CAE integrated approach for designing engine is proposed. As first step, some typological quantities are setting in order to define the designed engine, for example the number of cylinders, displacements, thermodynamic cycle and geometrical constraints. Using literature approach and tailored design methodologies, the developed software provides the geometric parameters of the main engine components: crankshaft, piston, wrist pin, connecting rod, bedplate, engine block, cylinder head, bearings, valvetrain. Form the geometrical parameters, the developed software, using 3D CAD parametric models, defines a first functional model of each component and of their mutual interactions. Then a numerical analysis can be evaluated and it provides important feedback result for design targets. In the paper the particular case of a crank mechanism model is presented. The assembly of crankshaft, pistons, wrist pins, connecting rods are modeled by means of a full parametric approach and driven by the first geometrical design. Then a numerical validation of the solution is done and a feedback procedure is taken into account. In that case, a structural modification on the crankshaft is used for a dynamic torsional requirement. The proposed software proves to be a useful and quick instrument for a conception of a new engine. As a consequence, it is an interesting method to reduce the design time and costs, allowing automatic optimization techniques. © 2011 SAE International.

Abstract: This paper presents a multi-physic modeling of an electromechanical energy scavenging device able to supply energy inside car tires for wireless sensors. A permanent magnet, connected to the inner liner of a tire, is accelerated along a guide by the tire deformation during car motion; by interacting with coils it generates a power which is conditioned by a proper electronic interfaced to an external load. The original approach implemented in this kind of device is the nonlinear dynamic properties designed and controlled: adaptive resonance in function of car velocity is optimized for increasing its global efficiency. The energy conversion process takes into account the simulation of different phenomena such as: non linear dynamic and adaptive resonant behavior of the seismic mass, electromagnetic and magneto-static coupling between moving mass and coils, transfer of the generated power to an external load by means of a nonlinear circuit interface. An integrated model of the cascaded energy steps is developed inside the Simulink/Stateflow environment. A good agreement is found in the comparison between theoretical model and experiments conducted on prototypes produced by means of drawings directly obtained from 3D CAD models. To compare these results to other energy harvesting devices found in Literature, the same device adapted with symmetric configuration is derived. Empirical formulas to measure efficiency are evaluated for this device and compared with Literature results. The accurate modeling of the energy conversion device is a breakthrough in the modeling of these kinds of devices and allows to reach interesting power/volume ratios: small dimensions (about one cubic centimeter) and relatively high power output (more than one milliwatt). Copyright © 2011 SAE International.

Abstract: In the present paper, starting from a first attempt design of engine components, a CAD/CAE integrated approach for designing engine is proposed. As first step, some typological quantities are setting in order to define the designed engine, for example the number of cylinders, displacements, thermodynamic cycle and geometrical constraints. Using literature approach and tailored design methodologies, the developed software provides the geometric parameters of the main engine components: crankshaft, piston, wrist pin, connecting rod, bedplate, engine block, cylinder head, bearings, valvetrain. Form the geometrical parameters, the developed software, using 3D CAD parametric models, defines a first functional model of each component and of their mutual interactions. Then a numerical analysis can be evaluated and it provides important feedback result for design targets. In the paper the particular case of a crank mechanism model is presented. The assembly of crankshaft, pistons, wrist pins, connecting rods are modeled by means of a full parametric approach and driven by the first geometrical design. Then a numerical validation of the solution is done and a feedback procedure is taken into account. In that case, a structural modification on the crankshaft is used for a dynamic torsional requirement. The proposed software proves to be a useful and quick instrument for a conception of a new engine. As a consequence, it is an interesting method to reduce the design time and costs, allowing automatic optimization techniques. Copyright © 2011 SAE International.

Abstract: The hazelnut production for food-farming field industry is made up of several processes and some of those could be suitable for performing virtual simulations. An aim for using simulations is to check the strong and weak features of the machineries and then apply suitable modifications. Both machineries and hazelnuts 3D models are then requested but, while machinery model is unique or the technical solution is represented through a deterministic sketch, hazelnut model must represent as good as possible its real statistical distribution of its characteristics. Then a parametric model of the hazelnut is useful for being a reference model whose parameters can be edited to generate a defined number of hazelnuts consistent with real distributions.

Keywords: 3D parametric model | Hazelnut | Stochastic simulation

Abstract: This paper presents a very compact electro-mechanical wideband energy harvester optimized for tire applications. The energy conversion process of the device takes into account the simulation of different phenomena like: non linear dynamic and adaptive resonant behavior of the seismic mass, electromagnetic and magneto-static coupling between floating magnetic mass and coils, transfer of the generated power to an external load by means of a nonlinear circuit interface. The paper is focused on the pneumatic effects of the floating magnet sliding into a calibrated guide. A convenient choice of clearance between moving and fixed parts can be used to create an effective air brake preventing or softening shocks with end stops and to modify system dynamic. A block-oriented Simulink®, experimentally validated, model has been realized to predict scavenger device performance and to optimize design parameters. Equivalent linearized stiffness and damping factors due to pneumatic effects have been modeled in the lumped parameters system to get a simplified model and to formalize relations with the geometrical characteristics. Analysis of the effect of several nonlinearities at different vehicle speed have been performed.

Keywords: Adaptive resonance | Electro-mechanical device | Energy scavenger

Abstract: This paper presents a multi-physic modeling of an electromechanical energy scavenging device. A permanent magnet, connected to the inner liner of a tyre, is accelerated along a guide by the tyre deformation during car motion; by interacting with coils it generates a power which is conditioned by a proper electronic interfaced to an external load. The energy conversion process takes into account the simulation of different phenomena like: dynamic behavior of the seismic mass, electromagnetic coupling between moving mass and coils, transfer of the generated power to an external load by means of a nonlinear circuit interface. An integrated model of the cascaded energy steps is developed inside the Simulink environment. A good agreement is found in the comparison between theoretical model and experiments. The accurate modeling of the energy conversion device is a breakthrough in the modeling of these kinds of devices and allows to reach interesting power/volume ratios: small dimensions (about one cubic centimeter) and relatively high power output (more than one milliwatt). © 2006 IEEE.

Keywords: Adaptive resonance | electro-mechanical device | energy scavenger

Abstract: The paper discusses a gearbox design method based on an optimization algorithm coupled to a full integrated tool to draw 3D virtual models, in order to verify both functionality and design. The aim of this activity is to explain how the state of the art of the gear design may be implemented through an optimization software for the geometrical parameters selection of helical gears of a manual transmission, starting from torque and speed time-histories, the required set of gear ratios and the material properties. This approach can be useful in order to use either the experimental acquisitions or the simulation results to verify or design all of the single gear pairs that compose a gearbox. Genetic algorithm methods are applied to solve the optimization problems of gears design, due to their capabilities of managing objective functions discontinuous, non-differentiable, stochastic, or highly non-linear. The final design tool, implemented in Matlab® environment, is based on the calculation of load capacity of helical gears, including the computation of tooth bending strength, of surface durability (pitting) and the estimation of service life under variable load, as suggested by International Standards. An automated macro procedure for Solidworks® interacts with the Matlab® environment to get the dimensional parameters of each gear and produces the models of each gear and their assembly. Copyright © 2010 SAE International.

Abstract: The paper approaches an educational application of 3D dynamic interactive images of medical devices. Manuals containing 3D images are considered more efficient than classic manuals. Combination of 3D interactive images with World Wide Web technologies makes the educational activities and especially the e-learning more attractive. Some web technologies used in creation of 3D interactivity were compared in order to choose a suitable environment for learning in the field of medical devices. Results of the study were used in the elaboration of an international e-learning platform in the frame of the Leonardo da Vinci educational program. The originality of the project consists in the interactivity of 3D images used in lessons. © 2009 IEEE.

Keywords: Images | Interactivity | Medical devices

Abstract: The superior mobility of a military vehicle provides the combat crew with a tactical advantage through increased cross country speed. The suspension system plays a fundamental role in evaluating a vehicle mobility. A mathematical model that allows realistic simulations of vehicles operating in a wide spectrum of environmental conditions may help to lower costs and time required during their development. The paper concerns with vehicle-terrain interaction modeling, for a military tracked tank, through multi-body and block-oriented approaches. It is focused on the consequences that the suspension system has got on the comfort and on the performance. Thus through a multi-body software a realistic three dimensional model of a tracked fighting vehicle is developed. This virtual model confirms some experimental data available on its longitudinal dynamics. In order to simplify the multi-body simulations, a block-oriented approach is adopted to develop a model of the same vehicle. Some dynamic simulations are discussed in order to validate the proposed models and to compare the two different approaches. Copyright © 2009 SAE International.

Abstract: From a theoretical point of view, people are used to think that the adoption of innovative business solutions, for optimizing the product lifecycle, should always guarantee a sufficient return on the investment (ROI), even if the concrete benefits that the investment has given to the company are sometimes difficult to evaluate. Looking at the technical literature it is possible to find a lot of ROI's estimation metrics for the evaluation of business strategies, even if after the analysis of the theoretical concepts no one faces with a real implementation of the methodology proposed. This paper proposes a solution, based on the key performance indicator (KPI) method, for evaluating the benefits introduced by the adoption of a Product Lifecycle Management (PLM) tool in a one of a kind company. The methods have been validated with its implementation into an Aerospace and Defence company (Alcatel Alenia Space), highlighting the improvement created by the implementation of the PLM solution in the everyday activities and showing the system's contribution for some key-process as configuration, change and documentation. © 2008 Elsevier B.V. All rights reserved.

Keywords: Collaborative management | Extended enterprise | One-of-a-kind company | Product development management | Product lifecycle management

Abstract: Objectives: The aim of this study was to evaluate the effects of scanning parameters on the precision of the data acquired using a facial laser scanner and to assess the reliability of automatic model recording in humans. Methods: Data were acquired using a laser scanner (Cyberware 3030RGB); analysis and measurements were performed with Rapid Form 2004 software. A mannequin and six volunteers were scanned to investigate the effects of environmental conditions, positioning, head orientation, and software procedures. Precision and accuracy of the data were evaluated comparing six linear measures calculated on scanned data with those obtained directly. Two sessions with different head inclination were performed. The reliability of repeated scans was also assessed measuring the distance between the surfaces reconstructed from two separate scans of the same subject, at 12 anatomical points, in 5 subjects, during two sessions using a different head inclination. Differences were analysed using paired t-tests or analysis of variance (ANOVA). Results: The accuracy of scanning was ±0.65 mm. The development of a specific protocol resulted in a mean scanning error of 1-1.2 mm and a recording error of 0.3-0.4 mm on repeated scans of human subjects. Conclusions: This study indicates that scanning of the human face may be hampered by errors and artefacts, mainly due to movements. While the effect of trembling and involuntary movements during the exam may be minimized using faster scanning devices, comparative observation over time may be affected by unreal differences due to the uncertainty of facial expression. The overall error is, however, in the range useful for most clinical studies. © 2006 The British Institute of Radiology.

Keywords: Anthropometry | Face | Three-dimensional imaging | Validation studies

Abstract: Objectives: To create and to spread a new interactive multimedia instrument, based upon virtual reality technologies, that allows both the running simulation of machines and equipment and the reproduction via Web of complex three-dimensional (3D) anatomical models such as the skull. Methods: There were two main aspects of the project, one of design engineering and the other biomedical engineering, for the creation of "artificial" and anatomical objects. The former were made with 3D Studio Max R4 by Autodesk, San Rafael, CA, while the latter were created starting from real bones scanned with a CT system or a surface scanner and elaborated with different programs (3D Studio Max R4, Scenebuilder by Viewpoint, New York, NY and Spinfire by Actify, San Francisco, CA). The 3D models were to be integrated into web modules and had to respect file limits while preserving a sufficient definition. Two systems of evaluation were used, a questionnaire on a selected sample and an external evaluation by a different university. Results: The Viewpoint format offers the best interactivity and size reduction (up to 96% from the original 3D model). The created modules included production of radiological images, rapid prototyping, and anatomy. The complete "3D Distant Learning Prototype" is available at www.webd.etsii.upm.es. Conclusions: The software currently available permits the construction of interactive modules. The verification on the selected sample and the evaluation by the University of Naples show that the structure is well organized and that the integration of the 3D models meets the requirements.

Keywords: Distant learning | Rapid prototyping | Web 3D

Abstract: Recent innovations in laser scanner technology provide a potentially useful technique for accurate three-dimensional (3D) documentation of the face. Aim of this study was to evaluate and optimise facial surface acquisition parameters and measurements obtained by a Cyberware colour laser scanner and to compare those measures to the common anthropometric ones made by individual examiners. This preliminary study indicates that 3D scanning is a sufficiently precise and repeatable surface 3D acquisition method.

Keywords: Anthropometry | Laser scanning | Three-dimensional face

Abstract: The paper deals with the automatic feature recognition of workpieces and families formation. To generate part families, the used approach utilizes a frame based representation system both for data and for features. A clustering method is used to toke into account the morphology, the dimensions as well as the manufacturing sequences of parts. Being the procedure a self learning one, the introduction of new parts into the families is relatively simple. © 1991 CIRP.

Keywords: Cluster analysis | Feature-based models | Group Technology

Abstract: Abstract: The main design principles and specifications of an experimental vertical boring mill built for high speed turning tests (up to over 100 m/s) are described, and some results of an investigation on turning steel with ceramic tool within a 15 to 50 m/s cutting speed range are discussed. Data on single and combined effects of machining parameters on surface finish, tool life, chip formation and cutting power were obtained in the tests, and their significance is assessed. © 1988 CIRP.

Keywords: Ceramic Tools | Cutting Power | Steel Turning | Surface Finish | Tool Performances

Abstract: A program for personal computer in Basic Language calculates the dimensions of the blank of the subsequent forms of a steel metal sheet used to obtain, by deep drawing, a piece with final rectangular plant. The calculation is followed by the plotting of the plant views of all the successive forms involved. The Authors are indebted to ROMANOWSKI's work, from which the procedure is drawn, and in particular for basic assumptions regarding the admissible drawing ratios and the algorithms to define the geometrical features of the forms. On the other hand they have developed a method of successive approximations, which is incorporated in the program, to minimize the number of intermediate forms and to optimize their dimensions. The program puts itself as a first step towards a more general handling of the problem. © 1985 CIRP.

Abstract: This work has been developed looking for the possibility to use the Electron-Jet drilling technique to produce the holes in Diesel motor's injection values. The paper may divided into two parts. The first one discusses the problem to determine the voltage - current relationship and it shows that a ratio "β "exists between appearent and theoretical electrolyte conductivity depending on supply voltage. The second part analyzes the ratio between the diameters of the nozzie and of the obtained note. It is demonstrated that this ratio is strongly dependent from supply voltage and Reynold's number of the electrolyte stream according to a non-Linear law. © 1981 CIRP.