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This paper considers the fitting of a CAD template model to tessellated data as strategy to implement a reverse engineering process that aims at the reconstruction of a parametric associative CAD model. The reconstruction methodology, called Template-Based CAD Reconstruction (TCRT), has been presented and fully discussed in a previous paper Buonamici et al. (J Comput Des Eng 5:145–159, 2018). The present paper focuses on the study of a fast and robust strategy to perform the fitting of the Template CAD Model to reference data. The study explores how different optimization strategies and evaluation metrics can affect a parametric CAD-fitting methodology. Two different optimization algorithms (PSO and GA) and three formulations of the objective function are tested to find the most effective combination. Reconstruction test cases are presented and discussed in the text. [ABSTRACT FROM AUTHOR]

Home-based recovery is gradually being used to reduce health-care costs; however, with a shorter stay in the hospital, the risk of growing adverse clinical outcomes exists, mainly due to the lack of motivation in the patient and on the difficulties in performing a strict control by the doctors. This is particularly true for patients who went under knee arthroplasty or total knee replacement who should strictly follow the effective recovery protocols delivered by the doctors. The development of tools for measuring the functional recovery of the operated joint is therefore deemed crucial both for the patient to feel motivated in performing the right number of exercises, and for the doctor that can follow him/her up remotely. One of the most recognized methods for assessing the correctness of a series of recovery exercises, is to monitor the pose of the patient in real-time so as to evaluate its posture in his range of motion. Accordingly, in this paper a novel hybrid approach to 3D human pose estimation is proposed. A first estimation of 2D body pose of the patient in the scene is given, then the depth information coming from the RGB-D sensor is exploited to estimate the joints 3D coordinates. The proposed algorithm proved to overcome the main limitation of using a pure 3D skeleton tracking algorithm during physiotherapy rehabilitation. [ABSTRACT FROM AUTHOR]

Autologous ear reconstruction is the preferred treatment in case of partial or total absence of the external ear. The surgery can be very challenging to perform and the aesthetic result highly dependent on the surgeon's "artistic skills". In this context a preoperative planning and simulation phase based on the patient's specific anatomy may result crucial for the surgical outcome. In this work, starting from a case study, the elements necessary for an effective simulation are identified and a strategy for their interactive design and customization is devised with a perspective of a semi-automatization of the procedure. [ABSTRACT FROM AUTHOR]

Planning prototyping strategies for conceptual design purposes is a crucial activity, which needs a clear understanding of the potentialities of the different typologies of prototype. Therefore, to prepare future designers, it is very important to provide the required information in design-related academic courses. However, prototypes and prototyping activities are often taught in specific courses with a major emphasis on the underpinning technologies, but with limited attention on design implications, especially about the fuzzy-front-end of the design process. The work presented in this paper aims at investigating about how students perceive the usefulness of prototypes during conceptual design activities, in order to provide first indications about the gap to be filled. To this purpose, two classes of students participated to an experimental session, and were asked to perform a conceptual design task individually. Subsequently, they participated to an on-line survey developed to gather information about the perceived usefulness of prototypes, in relation to the performed conceptual design activity. Several findings have been obtained from this work, but maybe the most impacting one concerns the different consideration that the two samples of students had about the fidelity of prototypes. Indeed, differently from what recently highlighted in current literature, it emerged that engineering students preferred low-fidelity prototypes. However, other unexpected evidences have been found, which highlight that at least for the considered institution, students still lack a comprehensive understanding of the design-related potentialities of prototypes. [ABSTRACT FROM AUTHOR]

This paper presents the implementation and investigation of a novel user centred method, adopted to design, develop and test a personal robot system, composed of a mobile robotic platform and a smart environment, for assisting people at home. As robots need to work closely with humans, novel interactive engineering design approaches are required to develop service robots that are adherent to end users’ needs and that can be quickly employed in daily life. Particularly, this paper presents a methodology based on the simultaneous evaluation of dependability and acceptability, thus leading to an innovative approach for metrics and benchmarks that includes not only the main technical attributes of dependability, but also the parameters of acceptability, both implemented via a user-centered design and co-creative approach. Additionally, dependability and acceptability form the basis for defining standardized methodologies to test and evaluate robotic systems in dedicated experimental infrastructures (or robotic facilities), which are conceived to facilitate engineers in their studies and assessments. [ABSTRACT FROM AUTHOR]

The percutaneous interventions in the treatment of structural heart diseases represent nowadays a viable option for patients at high risk for surgery. However, unlike during the traditional open heart surgery, the heart structures to be corrected are not directly visualized by the physician during the interventions. The interpretation of the available medical images is often a demanding task and needs specific skills i.e. clinical experience and complex radiological and echocardiographic analysis. The new trend for cardiovascular diagnosis, surgical planning and intervention is, today, mutually connected with most recent developments in the field of 3D acquisition, interactive modelling and rapid prototyping techniques. This is particularly true when dealing with complex heart diseases since 3D-based techniques can really help in providing an accurate planning of the intervention and to support surgical intervention. To help the research community in confronting with this new trend in medical science, the present work provides an overview on most recent approaches and methodologies for creating physical prototypes of patient-specific cardiac structures, with particular reference to most critical phases such as: 3D image acquisition, interactive image segmentation and restoration, interactive 3D model reconstruction, physical prototyping through additive manufacturing. To this purpose, first, recent techniques for image enhancement to highlight anatomical structures of interest are presented together with the current state of the art of interactive image segmentation. Finally, most suitable techniques for prototyping the retrieved 3D model are investigated so as to derive a number of criteria for manufacturing prototypes useful for planning the medical intervention. [ABSTRACT FROM AUTHOR]

Active noise control (ANC) techniques have been successfully investigated and implemented for the attenuation of stationary acoustic noise. Furthermore, adaptive methods for impulsive noise have been also presented in the literature, even though the considered statistical models are well suited only for a narrow class of impulsive disturbances that can be faced in realistic scenarios. In this paper, a preliminary study addressing the design of a non-adaptive deterministic ANC system for pulse signals is developed by avoiding any statistical assumption. The theory of Wave Field Synthesis is explicitly exploited in a destructive manner, that is, generating a canceling acoustic pressure field by means of arrays of secondary sources. An ad-hoc interactive software simulator implementing the proposed approach is realized and used to virtually explore the solution spaces of some test case scenarios. Simulations’ results considering linear and planar arrays in the case of free space propagation, as well as in the case of interaction with a hard ground, are presented and compared. Furthermore, the impact of different design solutions proposed to mitigate the impairments due to terrain reflections is evaluated. [ABSTRACT FROM AUTHOR]

Because of their features, pneumatic motors are often preferred to their electrical counterparts in a number of industrial applications. In spite of their growing diffusion, to the best of authors knowledge, a well-established design procedure is still missing due to the large number of factors (e.g. friction, fluid-dynamic losses, etc.) introducing non idealities in the motor behaviour. Moving from these considerations, this work aims to illustrate the development of a design methodology, implemented in the form of a prototypal software tool, capable of automatically define all the necessary constructive parameters of vane motors on the basis of a required characteristic curve and to considerably speed-up the whole design process. The methodology is based on three main elements: an experimental-mathematical model obtained by means of a DoE approach; a search algorithm meant to identify the constructive solution best matching the design target; a parametric CAD model which is directly driven by the constructive parameters provided by the mathematical model. The presented methodology, applied to the development of a set of pneumatic vane motors, led to the manufacturing of units fulfilling the design target within an error lower than 3 %, thereby demonstrating the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper illustrates a research work carried out in order to allow a comfort-oriented optimization of motorcycle saddles. The aim of the work is to develop a numerical tool (CAD/FEM) to assist the designer willing to take comfort into account as a primary requirement for saddle design. This paper briefly illustrates the basic steps of the methodology. The authors, after obtaining a set of parametric CAD models of both saddle and rider, simulated the contact occurring between these components by means of a FE solver, thereby obtaining a comfort level estimate. The results, validated by a set of experimental tests, can be used both to evaluate the comfort level of an existing saddle and to improve the saddle design. The work demonstrated the feasibility of the proposed approach, capable of providing useful hints for a comfort-oriented design, already from the early stage of stylistic design of motorcycle saddles and, possibly, of other products. [ABSTRACT FROM AUTHOR]