[Elenco soci]

De Crescenzio Francesca

Professore Associato

Università degli Studi di Bologna

Sito istituzionale
SCOPUS ID: 23972283300
Orcid: 0000-0003-2837-7742

Pubblicazioni scientifiche

[1] Santhosh S., De Crescenzio F., A Mixed Reality Application for Collaborative and Interactive Design Review and Usability Studies, Lecture Notes in Mechanical Engineering, 1505-1515, (2023). Abstract

Abstract: In recent days product design and review cycles are considerably held to many constraints and requirements. One of the main requirements regards the usability of solutions and the impact that design choices have on final users. Therefore, it is becoming crucial to anticipate human factors concerns in the preliminary phases of product development process. Also, since human factors affect the users subconsciously and influence the decision making in a significant way, they need to be enabled to observe the users while interacting with the product in real-time. In this framework, the platform that the human factors expert and the users use plays a vital role in influencing the human factor assessments and evaluations. Latest developments in Extended Reality opened the way toward the possibility to conceive new simulation platforms that allow experts to deeply explore the products in real-time through collaborative and interactive environments before the physical mockup of the product. The purpose of this paper is to outline a Mixed Reality (MR) tool in the field of aircraft interior design to demonstrate it as a potential co-creative platform for involving human factor experts in the loop while the task is ongoing. An MR multi-user, co-located, collaborative and interactive environment of an aircraft galley is developed where the HF specialist and flight crew member can co-exist to visualize the real scale model of the galley and perform an operational task. Such co-creative tool is foreseen to execute usability tests during design review phase and reduce time, costs of product development cycle while meeting the user requirements.

Keywords: Co-creation | Design review | Human factors and ergonomics | Mixed reality

[2] Ricci G., De Crescenzio F., Santhosh S., Magosso E., Ursino M., Relationship between electroencephalographic data and comfort perception captured in a Virtual Reality design environment of an aircraft cabin, Scientific Reports, 12(1), (2022). Abstract

Abstract: Successful aircraft cabin design depends on how the different stakeholders are involved since the first phases of product development. To predict passenger satisfaction prior to the manufacturing phase, human response was investigated in a Virtual Reality (VR) environment simulating a cabin aircraft. Subjective assessments of virtual designs have been collected via questionnaires, while the underlying neural mechanisms have been captured through electroencephalographic (EEG) data. In particular, we focused on the modulation of EEG alpha rhythm as a valuable marker of the brain’s internal state and investigated which changes in alpha power and connectivity can be related to a different visual comfort perception by comparing groups with higher and lower comfort rates. Results show that alpha-band power decreased in occipital regions during subjects’ immersion in the virtual cabin compared with the relaxation state, reflecting attention to the environment. Moreover, alpha-band power was modulated by comfort perception: lower comfort was associated with a lower alpha power compared to higher comfort. Further, alpha-band Granger connectivity shows top-down mechanisms in higher comfort participants, modulating attention and restoring partial relaxation. Present results contribute to understanding the role of alpha rhythm in visual comfort perception and demonstrate that VR and EEG represent promising tools to quantify human–environment interactions.

[3] De Crescenzio F., Fantini M., Asllani E., Generative design of 3D printed hands-free door handles for reduction of contagion risk in public buildings, International Journal on Interactive Design and Manufacturing, 16(1), 253-261, (2022). Abstract

Abstract: During the emergency caused by COVID 19 evidence has been provided about the risk of easily getting the virus by touching contaminated surfaces and then by touching eyes, mouth, or nose with infected hands. In view of the restarting of daily activities in presence, it is paramount to put in place any strategy that, in addition to social distancing, is capable to positively impact on the safety levels in public buildings by reducing such risk. The main aim of this paper is to conceive a design methodology, based on a digital, flawless, and sustainable procedure, for producing human-building interfacing solutions that allow anybody to interact in a safer and more comfortable way. Such solutions are focused on the adaptation of existing buildings features and are thought to be an alternative to sensor based touchless technology when this is not applicable due to economic or time constraints. The process is based on the integration of digital technologies such as 3D Scanning, Generative Design and Additive Manufacturing and is optimised to be intuitive and to be adaptive, hence, to be replicable on different kinds of surfaces. The design concept is finalised to generate automatically different products that meet geometry fitting requirements and therefore adapt to the specific geometries of existing handles. A specific case on Hands Free Door Handles is presented and the results of manufacturing and preliminary validation process are provided and discussed.

Keywords: Additive Manufacturing | Covid 19 | Generative Design | Reverse Engineering

[4] Santhosh S., De Crescenzio F., Vitolo B., Defining the Potential of Extended Reality Tools for Implementing Co-creation of User Oriented Products and Systems, Lecture Notes in Mechanical Engineering, 165-174, (2022). Abstract

Abstract: In the last two decades a huge number of interactive and collaborative applications of Virtual Environments for designing products has been proposed. Such applications have been recommended as tools to implement Human Centered Design Approach in experiments where potential users are involved in participatory design sessions before going for production. In this kind of experiments, we observe that users are mainly involved in the validation of solutions previously elaborated by designers while in the last decade the most innovative approach in the creation of solutions seems to be moving from a user centered design to a co-design or co-creation process. Thus, it is essential to have a platform where the elements of co-creation can be fulfilled in building a successful project. The purpose of this paper is to outline the concept of co-creation and the significance of co-creation platforms alongside of proposing innovative tools for building the co-creative environments. The paper aims to layout a classification of the Extended Reality (XR) tools currently available and of their functionality as valuable means to actually embed co-design and co-creation concepts in Virtual Environments evaluating the advantages that this can bring to Industry through field studies. A review of innovative solutions like Virtual, Augmented and Mixed reality technologies is examined and drawn towards the requirements of the concept through a literature research. Additionally, a co-creative environment for designing aircraft cabin interiors is conceived and discussed a with company representative.

Keywords: Co-creation | Collaboration | Extended reality | Interaction platforms

[5] De Crescenzio F., Bagassi S., Starita F., Preliminary user centred evaluation of regional aircraft cabin interiors in virtual reality, Scientific Reports, 11(1), (2021). Abstract

Abstract: The main aim of the CASTLE (Cabin System Design Towards Passenger Wellbeing) European project is to deliver innovative interiors solutions that maximize the comfort and wellbeing of passengers in the next future. To achieve such objective, an effective HCD (Human Centred Design) approach has been employed to derive a Human Response Model based on a holistic assessment of comfort. The overall methodology has been conceived to provide different tools and methods to collect data on the impact that the design of each cabin item has on the user from the earliest design stages. One of these tools is represented by using 3D virtual mock-ups to capture data on the user’s perception and to rate the level of appreciation inspired by the specific design. In this paper we present the experimental procedures and the results from a preliminary experimental campaign of Human in the loop simulations in Virtual/Augmented Reality of a Regional Aircraft.

[6] Bagassi S., De Crescenzio F., Piastra S., Persiani C.A., Ellejmi M., Groskreutz A.R., Higuera J., Human-in-the-loop evaluation of an augmented reality based interface for the airport control tower, Computers in Industry, 123, (2020). Abstract

Abstract: An innovative airport control tower concept based on the use of modern augmented reality technologies has been developed and validated by means of human-in-the-loop experiments in a simulated environment. An optical-based augmented reality interface underpins the proposed concept that consists in providing air traffic control operators in the airport control tower with complete head-up information, as opposed to the current mix of information retrieval through both head-up real view and head-down interfaces. Specific measurement of the time spent by the operator working in either head-up or head-down position, show that the proposal has a clear effect in stimulating the air traffic control operator to work in a head-up position more than in a head-down position, with positive effects on his/her situational awareness and perceived workload, especially when dealing with low visibility conditions operational scenarios.

[7] Bagassi S., De Crescenzio F., Piastra S., Augmented reality technology selection based on integrated QFD-AHP model, International Journal on Interactive Design and Manufacturing, 14(1), 285-294, (2020). Abstract

Abstract: In the last decade, Augmented Reality has become increasingly popular. As improved performances are gathered in terms of mature hardware and software tools, we are observing the stemming of a huge number of applications of this technology both in the entertainment and in the industrial domains. On the one hand, such applications are usually claimed to bring benefits in terms of productivity or enhancement of the human’s capability to perform tasks. On the other hand, researchers and developers seem not to adequately consider the different meanings that AR assumes when implemented through visualization devices that can differ significantly in nature and in their capability to provide a mixed real-virtual scenario. In this paper, we describe a user-centred method based on an integrated QFD-AHP approach to select the best visualization display technology with regard to a specific application context. The aim is to establish a repeatable and documented process for the identification of the technology that best suits and mitigates the acceptability risks of the transition from a legacy working environment to an AR based operational environment. The method has been developed in the framework of the RETINA (Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision) project involving the end users, in this case, air traffic controllers. Nevertheless, it can be generalised and applied to other contexts of use. Furthermore, in order to be resilient to the fast, technological development in AR, it can be used to update the results as improvements arise in the performance level of the display devices in a specific technology.

Keywords: Air traffic control | Analytic hierarchy process (AHP) | Augmented reality | Human machine interface | Quality function deployment (QFD)

[8] Di Flumeri G., De Crescenzio F., Berberian B., Ohneiser O., Kramer J., Aricò P., Borghini G., Babiloni F., Bagassi S., Piastra S., Brain–Computer Interface-Based Adaptive Automation to Prevent Out-Of-The-Loop Phenomenon in Air Traffic Controllers Dealing With Highly Automated Systems, Frontiers in Human Neuroscience, 13, (2019). Abstract

Abstract: Increasing the level of automation in air traffic management is seen as a measure to increase the performance of the service to satisfy the predicted future demand. This is expected to result in new roles for the human operator: he will mainly monitor highly automated systems and seldom intervene. Therefore, air traffic controllers (ATCos) would often work in a supervisory or control mode rather than in a direct operating mode. However, it has been demonstrated how human operators in such a role are affected by human performance issues, known as Out-Of-The-Loop (OOTL) phenomenon, consisting in lack of attention, loss of situational awareness and de-skilling. A countermeasure to this phenomenon has been identified in the adaptive automation (AA), i.e., a system able to allocate the operative tasks to the machine or to the operator depending on their needs. In this context, psychophysiological measures have been highlighted as powerful tool to provide a reliable, unobtrusive and real-time assessment of the ATCo’s mental state to be used as control logic for AA-based systems. In this paper, it is presented the so-called “Vigilance and Attention Controller”, a system based on electroencephalography (EEG) and eye-tracking (ET) techniques, aimed to assess in real time the vigilance level of an ATCo dealing with a highly automated human–machine interface and to use this measure to adapt the level of automation of the interface itself. The system has been tested on 14 professional ATCos performing two highly realistic scenarios, one with the system disabled and one with the system enabled. The results confirmed that (i) long high automated tasks induce vigilance decreasing and OOTL-related phenomena; (ii) EEG measures are sensitive to these kinds of mental impairments; and (iii) AA was able to counteract this negative effect by keeping the ATCo more involved within the operative task. The results were confirmed by EEG and ET measures as well as by performance and subjective ones, providing a clear example of potential applications and related benefits of AA.

Keywords: adaptive automation | air traffic control | electroencephalography | eye-tracking | human–machine interface | Out-Of-The-Loop | passive brain–computer interface | vigilance

[9] De Crescenzio F., Bagassi S., Asfaux S., Lawson N., Human centred design and evaluation of cabin interiors for business jet aircraft in virtual reality, International Journal on Interactive Design and Manufacturing, 13(2), 761-772, (2019). Abstract

Abstract: In the recent past a growing attention to the passenger is emerging overall in the transport domain. Hence, maximising the quality of travelling from the human’s point of view is a new challenge especially in those fields, such as aeronautics, in which technical efficiency, capacity and sustainability have traditionally driven the design process of systems and subsystems. In this context it is crucial to implement an efficient human centred design process in order to foresee the capability of a specific cabin interiors design of meeting the user’s expectations, including the needs related to comfort and well being. By using virtual reality technologies as a vehicle/platform, it allows the users/passengers to experience the interior environment of the cabin long before the actual development and manufacturing of the full size demonstrator. Due to the complex nature of aerospace programmes, typically taking ‘many’ years to develop and productionise, technologies which help reduce programme risk and potential delays are hugely beneficial to all partners involved. In this paper we present the results of a virtual reality based evaluation campaign specifically conceived for the collection of potential users’ feedback in the design of innovative and breakthrough solutions for the business jet industry. The main issues have regarded the identification of the expectation for such an elitist population and the creation of a Virtual Environment to explore the entire cabin as a holistic approach and innovative passenger experience. The work has been performed in the framework the Horizon 2020 project CASTLE (Cabin Systems Design Toward Passenger Well-being).

Keywords: Aircraft design | Cabin interiors | Comfort | Human centred design | Virtual reality

[10] Magosso E., De Crescenzio F., Ricci G., Piastra S., Ursino M., EEG alpha power is modulated by attentional changes during cognitive tasks and virtual reality immersion, Computational Intelligence and Neuroscience, 2019, (2019). Abstract

Abstract: Variations in alpha rhythm have a significant role in perception and attention. Recently, alpha decrease has been associated with externally directed attention, especially in the visual domain, whereas alpha increase has been related to internal processing such as mental arithmetic. However, the role of alpha oscillations and how the different components of a task (processing of external stimuli, internal manipulation/representation, and task demand) interact to affect alpha power are still unclear. Here, we investigate how alpha power is differently modulated by attentional tasks depending both on task difficulty (less/more demanding task) and direction of attention (internal/external). To this aim, we designed two experiments that differently manipulated these aspects. Experiment 1, outside Virtual Reality (VR), involved two tasks both requiring internal and external attentional components (intake of visual items for their internal manipulation) but with different internal task demands (arithmetic vs. reading). Experiment 2 took advantage of the VR (mimicking an aircraft cabin interior) to manipulate attention direction: It included a condition of VR immersion only, characterized by visual external attention, and a condition of a purely mental arithmetic task during VR immersion, requiring neglect of sensory stimuli. Results show that: (1) In line with previous studies, visual external attention caused a significant alpha decrease, especially in parieto-occipital regions; (2) Alpha decrease was significantly larger during the more demanding arithmetic task, when the task was driven by external visual stimuli; (3) Alpha dramatically increased during the purely mental task in VR immersion, whereby the external stimuli had no relation with the task. Our results suggest that alpha power is crucial to isolate a subject from the environment, and move attention from external to internal cues. Moreover, they emphasize that the emerging use of VR associated with EEG may have important implications to study brain rhythms and support the design of artificial systems.

[11] Cañas J.J., Ferreira P., de Frutos P.L., Puntero E., López E., Gómez-Comendador F., de Crescenzio F., Lucchi F., Netjasov F., Mirkovic B., Mental Workload in the Explanation of Automation Effects on ATC Performance, Communications in Computer and Information Science, 1012, 202-221, (2019). Abstract

Abstract: Automation has been introduced more and more into the role of air traffic control (ATC). As with many other areas of human activity, automation has the objective of reducing the complexity of the task so that performance is optimised and safer. However, automation can also have negative effects on cognitive processing and the performance of the controllers. In this paper, we present the progress made at AUTOPACE, a European project in which research is carried out to discover what these negative effects are and to propose measures to mitigate them. The fundamental proposal of the project is to analyse, predict, and mitigate these negative effects by assessing the complexity of ATC in relation to the mental workload experienced by the controller. Hence, a highly complex situation will be one with a high mental workload and a low complex situation will be one in which the mental workload is low.

Keywords: Air-traffic controllers | Automation | Mental workload

[12] Bagassi S., Lucchi F., De Crescenzio F., Piastra S., Design for comfort: Aircraft interiors design assessment through a human centered response model approach, 31st Congress of the International Council of the Aeronautical Sciences, ICAS 2018, (2018). Abstract

Abstract: In a highly competitive global aviation environment, European regional aircraft requires continuous improvements in cabin comfort. This paper describes the design for comfort process proposed in an industrial research project, aimed at the definition of innovative design approaches to measure the affective impact on a potential user when living in and interacting with the cabin. The study is performed in the framework of CASTLE (CAbin Systems design Toward passenger welLbEing). CASTLE is a project granted under the Horizon 2020 EU's research programme in the framework of the Clean Sky 2 initiative. Requirements and recommendations for the comfort aspects to be taken into account to develop a regional aircraft's cabin were provided by Leonardo's Aircraft Division. The methodological approach is set up in a Virtual / Augmented Reality Environment for the definition of a Human Centered Response Model for the design for comfort of regional aircraft interiors. In this context, special attention has been paid to the improvements that can be brought to the cabin interiors, and specifically to the experience that passengers can live in the aircraft of the future. The main objective of the project is to conceive, develop, prototype and test cabin interiors solutions following a HCD (Human Centered Design) methodology. The paper analyzes the approach toward the definition of the design for comfort according to the considered cabin items and design requirements. The proper comfort metrics are selected and linked to an experimental protocol analysis for their assessment. A Virtual Reality environment has been set up to support the comfort assessment in aircraft cabin interiors, from their preliminary design.

Keywords: Aircraft interiors Design | Comfort | Emotional Design | Human Centered Design | Virtual Reality

[13] Bagassi S., De Crescenzio F., Piastra S., The use of synthetic vision tools in the control tower environment: The retina concept, 31st Congress of the International Council of the Aeronautical Sciences, ICAS 2018, (2018). Abstract

Abstract: The Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision (RETINA) project is one of the selected Single European Sky ATM Research (SESAR) exploratory research projects on High Performing Airport Operations and it investigates the potential and applicability of Virtual/Augmented Reality (V/AR) technologies for the provision of Air Traffic Control (ATC) service by the airport control tower. The project assesses whether those concepts that stand behind tools such as Head-Mounted Displays (HUDs), Enhanced Vision Systems (EVSs) and Synthetic Vision Systems (SVS) can be transferred to ATC with relatively low effort and substantial benefits for controllers' Situational Awareness (SA). In doing so, two different augmented reality systems are investigated: Spatial Displays (SD) that, potentially, can be made to coincide with the tower windows and See-Through Head-Mounted Displays (ST-HMD). In this context the RETINA concept will enable the Air Traffic Controller to have a head-up view of the airport traffic even in low visibility conditions, similar to the vision currently provided in the cockpit with Head-Up displays. In the two-year project, the RETINA concept was developed, implemented and validated by means of human-in-the-loop simulations where the external view is provided to the user through a high fidelity 3D digital model in an immersive environment.

Keywords: Air Traffic Control | Airport Control Tower | Augmented Reality | Synthetic Vision

[14] Berberian B., Ohneiser O., de Crescenzio F., Babiloni F., di Flumeri G., Hasselberg A., MINIMA project: Detecting and mitigating the negative impact of automation, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 10275 LNAI, 87-105, (2017). Abstract

Abstract: In this paper, we present the preliminary steps conducted in the framework of the research project Mitigating Negative Impacts of Monitoring high levels of Automation (MINIMA). The main objectives of MINIMA are (i) to develop vigilance and attention neuro-physiological indexes, and (ii) to implement them in a system that can adapt its behavior and guide the operator’s attention. The goal is to mitigate negative impacts of the foreseen increasing automation in future Air Traffic Control (ATC) scenarios on Air Traffic Controller (ATCo) performance. The first step of research activities consists of better comprehension of Out-Of-The-Loop (OOTL) phenomena and of current methods to measure and compensate such effects. Based on this State of the Art, we propose the MINIMA concept, i.e. a dynamic adaptation of the task environment which is foreseen as a major requirement to keep the human ‘in the loop’, perfectly aware of the traffic situation. In the second part of this paper, we give details about the highly automated Terminal Manoeuvring Area selected as case study. Additionally, we describe the adaptation mechanisms that are planned to be implemented into this task environment and analyzed in the MINIMA project. Finally, the document provides information about the technical implementation of the vigilance and attention measurement that will be used to trigger adaptation of the task environment.

Keywords: Adaptive task and support activation | Air traffic controller | Attention | Attention guidance | Automation | Electroencephalography | Terminal Manoeuvring Area | Vigilance

[15] Fantini M., De Crescenzio F., Brognara L., Baldini N., Design and rapid manufacturing of a customized foot orthosis: A first methodological study, Lecture Notes in Mechanical Engineering, 0, 457-467, (2017). Abstract

Abstract: A feasibility study was performed in order to demonstrate the benefits of designing and manufacturing a customized foot orthosis by means of digital technologies, such as Reverse Engineering (RE), Generative Design (GD) and Additive Manufacturing (AM). The aim of this work was to define the complete design-manufacturing process, starting from the 3D scanning of the human foot anatomy to the direct fabricating of the customized foot orthosis. Moreover, this first methodological study tries to combine a user-friendly semi-automatic modelling approach with the use of low-cost devices for the 3D laser scanning and the 3D printing processes. Finally, the result of this approach, based on digital technologies, was also compared with that achieved by means of conventional manual techniques.

Keywords: Additive manufacturing | Computer aided design | Foot orthosis | Generative design | Reverse engineering

[16] De Crescenzio F., Lucchi F., Design for additive manufacturing of a nonassembly robotic mechanism, Lecture Notes in Mechanical Engineering, 0, 251-259, (2017). Abstract

Abstract: The growing potential of additive manufacturing technologies is currently being boosted by their introduction in directly manufacturing of ready-to-use products or components, regardless of their shape complexity. Taking advantage from this capability, a full set of new solutions to be explored is related to the possibility to directly manufacture joints or mechanisms as a unibody structure. In this paper, the preliminary design of a robotic mechanism is presented. The component is designed in order to be manufactured as a unibody structure by means of an Additive Manufacturing technology. Fused Deposition Modelling technique is used to print the mechanic arm as a single component, composed by different functional parts already assembled in the CAD model. Soluble support material is commonly used to support undercuts: in this case it is also deposited in the space between two adjacent parts of the same component, in order to allow the relative motion and the kinematic connection between them. The design process considers component optimization in relation to both the specific manufacturing technique and both the interaction between the different parts of the same component, in order to guarantee the proper relative motions. The conceived mechanism consists in a robotic structure in which the mechanical arm is bounded to a base and connected to a plier on the opposite side. The effect of clearance between all the kinematic parts is evaluated in order to assess mechanism degree of mobility in relation to the manufacturing process and components tolerances and geometry.

Keywords: Additive Manufacturing | Clearance assessment | Design Methods | Fused Deposition Modeling technique | Unibody mechanism manufacturing

[17] Fantini M., Curto M., De Crescenzio F., TPMS for interactive modelling of trabecular scaffolds for bone tissue engineering, Lecture Notes in Mechanical Engineering, 0, 425-435, (2017). Abstract

Abstract: The aim of regenerative medicine is replacing missing or damaged bone tissues with synthetic grafts based on porous interconnected scaffolds, which allow adhesion, growth, and proliferation of the human cells. The optimal design of such scaffolds, in the Bone Tissue Engineering field, should meet several geometrical requirements. First, they have to be customized to replicate the skeletal anatomy of the patient, and then they have to provide the proper trabecular structure to be successfully populated by the cells. Therefore, for modelling such scaffolds, specific design methods are needed to conceive extremely complex structures by controlling both macro and micro shapes. For this purpose, in the last years, the Computer Aided Design of Triply Periodic Minimal Surfaces has received considerable attention, since their presence in natural shapes and structures. In this work, we propose a method that exploit Triply Periodic Minimal Surfaces as unit cell for the development of customized trabecular scaffolds. The aim is to identify the mathematical parameters of these surfaces in order to obtain the target requirements of the bone grafts. For that reason, the method is implemented through a Generative Design tool that allow to interactively controlling both the porosity and the pores size of the scaffolds.

Keywords: Bone tissue engineering | Generative design | Scaffold design | Triple periodic minimal surfaces

[18] Fantini M., Curto M., De Crescenzio F., A method to design biomimetic scaffolds for bone tissue engineering based on Voronoi lattices, Virtual and Physical Prototyping, 11(2), 77-90, (2016). Abstract

Abstract: In regenerative medicine, 3D scaffolds are used to sustain the regeneration of tissues in removed or damaged parts of the human body. As such practices are being widely experimented in clinical applications, the design, the materials and the manufacturing process to obtain efficient 3D biocompatible lattices are being significantly investigated. Nevertheless, most of the proposed designs are based on regular 3D shapes obtained from the repetition of unit cells disposed in a three-dimensional array. This approach does not exploit the whole potential of computer-aided design tools coupled with manufacturing capabilities for freeform shapes. In this paper, we propose a method to model biomimetic lattices controlling the porosity and the pores size of scaffolds to be integrated with the anatomical shape of the defect. The method has been implemented in bone tissue case study and implements a generative design approach based on Voronoi diagrams.

Keywords: 3D scaffolds | generative design | Voronoi diagram

[19] Bagassi S., Lucchi F., De Crescenzio F., Persiani F., Generative design: Advanced design optimization processes for aeronautical applications, 30th Congress of the International Council of the Aeronautical Sciences, ICAS 2016, (2016). Abstract

Abstract: Current researches on aircraft design aim to reduce airplanes and components weights, optimizing aircraft performances and contributing to the challenge of reducing fuel consumption and operational costs. In this perspective novel materials and technologies are developed, but also advances in design methods and tools. Generative Design is a novel approach to automatically optimize component design. The design process has to be designed itself to achieve the optimal solution, in relation to design parameters, requirements and limits. Which peculiar features justify considering this technique to be a substantial step forward with respect to classical MDO? Could Generative Design be only an important, but not particularly differentiated approach for the design of (aerospace) structures and possibly systems of a higher level? For example, when the design goal is to find the best configuration of a structure, does generative design lead to the discovery of new concepts, or types of structures, or it is a particular application of genetic algorithms to topological optimization? This paper aims to contribute to give an answer to the previous questions. Specifically, the generative design approach is expected to be able to select between basic concepts and use these as the basic instructions and ingredients of a recipe for the design of a new system. By these considerations, in this paper, we revised the improvements brought by Generative Design principles within the traditional design procedure in aeronautics, considering Additive Manufacturing technology.

Keywords: Additive manufacturing | Aircraft design | Design methods | Generative design | Materials and processes

[20] Bagassi S., De Crescenzio F., Lucchi F., Masotti N., Augmented and virtual reality in the airport control tower, 30th Congress of the International Council of the Aeronautical Sciences, ICAS 2016, (2016). Abstract

Abstract: As a matter of fact, airports are considered as the bottleneck to increasing the capacity of the overall Air Traffic Management (ATM) system. While augmenting throughput in high performing airport operations, attention has rightly been placed on doing it in a safe manner. Many of the advances in airport operational safety come in the form of visualization tools for tower controllers. The increasing interest in Synthetic Vision (SV) and Augmented Reality (AR) technologies has led various analysts to positively esteem the adoption of new tools enabling both pilots and controllers to seamlessly operate under Visual Meteorological Conditions and Instrument Meteorological Conditions. This paper presents the motivations, the objectives, the proposed methodology and the expected impacts of the RETINA (Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision) project that has recently been granted by the SESAR (Single European Sky Air Traffic Management Research) Joint Undertaking. The two-years exploratory research project will investigate the potential and applicability of SV tools and Virtual/Augmented Reality (V/AR) display techniques for the Air Traffic Control (ATC) service provision by the airport control tower.

Keywords: Air traffic control | Augmented reality | Synthetic vision | Virtual reality

[21] Masotti N., Bagassi S., De Crescenzio F., Augmented reality for the control tower: The RETINA concept, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 9768, 444-452, (2016). Abstract

Abstract: The SESAR (Single European Sky Air Traffic Management Research) Joint Undertaking has recently granted the Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision project within the framework of the H2020 research on High Performing Airport Operations. Hereafter, we describe the project motivations, the objectives, the proposed methodology and the expected impacts, i.e. the consequences of using virtual/augmented reality technologies in the control tower.

Keywords: Air Traffic Control | Airport tower | Synthetic vision | Virtual/augmented Reality

[22] Masotti N., De Crescenzio F., Bagassi S., Augmented reality in the control tower: A rendering pipeline for multiple head-tracked head-up displays, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 9768, 321-338, (2016). Abstract

Abstract: The purpose of the air traffic management system is to accomplish the safe and efficient flow of air traffic. However, the primary goals of safety and efficiency are to some extent conflicting. In fact, to deliver a greater level of safety, separation between aircrafts would have to be greater than it currently is, but this would negatively impact the efficiency. In an attempt to avoid the trade-off between these goals, the long-range vision for the Single European Sky includes objectives for operating as safely and efficiently in Visual Meteorological Conditions as in Instrument Meteorological Conditions. In this respect, a wide set of virtual/augmented reality tools has been developed and effectively used in both civil and military aviation for piloting and training purposes (e.g., Head-Up Displays, Enhanced Vision Systems, Synthetic Vision Systems, Combined Vision Systems, etc.). These concepts could be transferred to air traffic control with a relatively low effort and substantial benefits for controllers’ situation awareness. Therefore, this study focuses on the see-through, head-tracked, head-up display that may help controllers dealing with zero/low visibility conditions and increased traffic density at the airport. However, there are several open issues associated with the use of this technology. One is the difficulty of obtaining a constant overlap between the scene-linked symbols and the background view based on the user’s viewpoint, which is known as ‘registration’. Another one is the presence of multiple, arbitrary oriented Head-Up Displays (HUDs) in the control tower, which further complicates the generation of the Augmented Reality (AR) content. In this paper, we propose a modified rendering pipeline for a HUD system that can be made out of several, arbitrary oriented, head-tracked, AR displays. Our algorithm is capable of generating a constant and coherent overplay between the AR layer and the outside view from the control tower. However a 3D model of the airport and the airport’s surroundings is needed, which must be populated with all the necessary AR overlays (both static and dynamic). We plan to use this concept as a basis for further research in the field of see-through HUDs for the control tower.

Keywords: Air traffic control tower | Augmented reality | Head-up display

[23] Fantini M., De Crescenzio F., Ciocca L., Persiani F., Additive manufacturing to assist prosthetically guided bone regeneration of atrophic maxillary arches, Rapid Prototyping Journal, 21(6), 705-715, (2015). Abstract

Abstract: Purpose - The purpose of this paper is to describe two different approaches for manufacturing pre-formed titanium meshes to assist prosthetically guided bone regeneration of atrophic maxillary arches. Both methods are based on the use of additive manufacturing (AM) technologies and aim to limit at the minimal intervention the bone reconstructive surgery by virtual planning the surgical intervention for dental implants placement. Design/methodology/approach - Two patients with atrophic maxillary arches were scheduled for bone augmentation using pre-formed titanium mesh with particulate autogenous bone graft and alloplastic material. The complete workflow consists of four steps: three-dimensional (3D) acquisition of medical images and virtual planning, 3D modelling and design of the bone augmentation volume, manufacturing of biomodels and pre-formed meshes, clinical procedure and follow up. For what concerns the AM, fused deposition modelling (FDM) and direct metal laser sintering (DMLS) were used. Findings - For both patients, a post-operative control CT examination was scheduled to evaluate the progression of the regenerative process and verify the availability of an adequate amount of bone before the surgical intervention for dental implants placement. In both cases, the regenerated bone was sufficient to fix the implants in the planned position, improving the intervention quality and reducing the intervention time during surgery. Originality/value - A comparison between two novel methods, involving AM technologies are presented as viable and reproducible methods to assist the correct bone augmentation of atrophic patients, prior to implant placement for the final implant supported prosthetic rehabilitation.

Keywords: CAD/CAM | Computed tomography | Implant surgery | Rapid prototyping | Titanium mesh

[24] Frau G., de Crescenzio F., Taurino D., Graphic visualization of probabilistic traffic/trajectory predictions in mobile applications. A first prototype and evaluations for general aviation purposes, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 9171, 154-164, (2015). Abstract

Abstract: The present work describes the interactive prototype and the preliminary evaluation results of a tool dedicated to the light General Aviation pilot’s community. The tool’s interface has been developed through an Android tablet application and aims at supporting the pilots in the task of staying “well-clear” from the surrounding traffic by presenting them the long-term prediction of the flights. The initial results and the approach of a heuristic evaluation conducted with five experts coming from the fields of user-experience, aviation and automotive are discussed along with the improvements in the design of the user-interface focusing on the trajectory depictions.

Keywords: Heuristic evaluation | Light general aviation | Trajectory prediction visualization | User-interface design

[25] De Crescenzio F., Lucchi F., Mezannar N., Persiani F., Using BCIS (brain computer interfaces) to evaluate emotional perception of passenger cabin design in virtual environments, 29th Congress of the International Council of the Aeronautical Sciences, ICAS 2014, (2014). Abstract

Abstract: Cabin interiors design can be considered one of the key enablers to face the societal challenges of future air transport. The cabin is the interface between the aircraft and the passenger and it strongly impacts on the user's experience. The quality of the travelling depends on the quality of the cabin. It could be measured through several and different dimensions, such as passenger's efficiency during and after the flight and the level of comfort that he/she experiences. Therefore, reading or working while flying or feeling restored when leaving the cabin should be the key performance indicators of a comfortable cabin. In this paper we propose an innovative design tool, that is an objective method to measure the affective impact that interior design provokes to passengers, with particular regards to seat design. Such method is based on the use of large virtual environments, coupled with BCIs (Brain Computer Interfaces). We propose a novel and original framework to correlate the BCIs affective scales to a set of comfort indicators. Experimental results are presented and discussed.

Keywords: Aircraft cabin layout | Aircraft design | Brain computer interfaces | Virtual reality

[26] Fantini M., De Crescenzio F., Ciocca L., Design and manufacturing of customized surgical devices for mandibular rehabilitation, International Journal on Interactive Design and Manufacturing, 7(4), 227-237, (2013). Abstract

Abstract: In this paper we report the application of CAD/CAM based technologies for the innovative development of customized surgical devices to assist the mandibular rehabilitation in both primary surgery (resection and reconstruction) and secondary surgery (only reconstruction). Design and manufacturing of such customized surgical device are conducted according to the virtual pre-operative planning of the surgeon and with the aim to transferring this planning into the operating theatre. In the case of primary surgery, a cutting guide is developed to assist the resection step while a bone plate is developed to assist the reconstruction step. Instead, in the case of secondary surgery, in addition to the bone plate to support the reconstruction, also a repositioning guide is designed to bring back to the original position the resected stumps according to the original shape of the mandible. Finally, the components of the surgical devices are manufactured by DMLS in alloys suitable for biomedical applications. © 2012 Springer-Verlag France.

Keywords: 3D Reconstruction | Computed tomography | Computer aided design | Direct metal laser sintering | Rapid prototyping

[27] De Crescenzio F., Frau G., Design of virtual reality based HMIs (Human Machine Interfaces) of complex systems, Proceedings of the International Symposium and Workshop on Engineering of Computer Based Systems, 181-186, (2013). Abstract

Abstract: Aeronautical transport system is rapidly growing and more demanding. It has become a total system of complex systems in which the human is recognized as the decisional point that is asked to act quickly and safely. In this context, innovative technologies provide the challenge to design revolutionary Human Machine Interfaces for the people involved.In this paper a report of recent works in Human Machine Interfaces in aeronautics developed at the University of Bologna is presented. Synthetic visualization and task automation are the main commonalities in these projects. What we can expect from the future is then explored through an insight into technological aspects. © 2013 IEEE.

Keywords: Human Machine Interface | Synthetic Displays | Virtual Reality

[28] Fantini M., De Crescenzio F., Ciocca L., Design and Rapid Manufacturing of anatomical prosthesis for facial rehabilitation, International Journal on Interactive Design and Manufacturing, 7(1), 51-62, (2013). Abstract

Abstract: In this work a novel design and manufacturing procedure have been experimented in order to improve the production of implant-supported nasal prosthesis. The complete workflow was divided into three main steps: data capture, prosthesis design and prosthesis manufacturing. First, the data capturing of the patient's face was obtained by means of 3D laser scanning. Then, design and manufacturing phases were carried out through CAD-CAM procedures and Rapid Prototyping technologies to obtain the mold for the silicone processing and the substructure for the retention of the prosthesis. Moreover, to design the customized prosthesis based on real anatomic shapes, a novel "Ear&Nose Digital Library" was developed in the framework of a multidisciplinary project with the involvement of students from medicine and engineering faculties. Advantages in terms of improvement of retention and cost reduction are presented. © 2012 Springer-Verlag.

Keywords: Facial rehabilitation | Prosthesis design | Rapid Prototyping | Reverse Engineering

[29] Ciocca L., Fantini M., de Crescenzio F., Corinaldesi G., Scotti R., CAD-CAM prosthetically guided bone regeneration using preformed titanium mesh for the reconstruction of atrophic maxillary arches, Computer Methods in Biomechanics and Biomedical Engineering, 16(1), 26-32, (2013). Abstract

Abstract: The protocol presented here is intended to minimise the intervention in bone reconstruction surgery when severe atrophy or deformity is present in the maxillary arches. A patient underwent augmentation of an atrophic maxillary arch using titanium mesh and particulate autogenous plus bovine demineralised bone. After computed tomography data elaboration, computer-aided design and computer-aided machining were used to plan the augmentation of bone volume to improve the implant position needed to support the final dental prosthesis. The augmented maxilla was rapidly prototyped in plastic, and the titanium mesh was tested on this model before the surgical intervention. Then, the preformed titanium mesh was implanted in the maxillary arch with bone grafting. The bone was augmented relative to the position of the implants for the definitive fixed implant-supported rehabilitation. The protocol presented here is a viable, reproducible way to determine the correct bone augmentation for the final implant-supported prosthetic rehabilitation. © 2013 Copyright Taylor and Francis Group, LLC.

Keywords: bone augmentation | bone graft | computed tomography | dental implants | rapid prototyping

[30] Bagassi S., De Crescenzio F., Lucchi F., Persiani F., Innovation in man machine interfaces: Use of 3D conformal symbols in the design of future HUDs (Head Up Displays), 28th Congress of the International Council of the Aeronautical Sciences 2012, ICAS 2012, 6, 4711-4720, (2012). Abstract

Abstract: Advantages of using HUDs in aviation have been already proven and this technology is widely being applied both in civil and military flight operations. HUDs are based on displaying data on a transparent layer allowing the pilot to simultaneously look at them and the outside world by means of a collimated projection. Commercial HUDs differ in the nature of the data they display and in the design of the interface. A considerable interest is currently being focused on the possibility of displaying conformal symbology, intended as geo-referenced symbols (as opposed to nonconformal navigation data), representing data that are usually displayed onto HDDs (Head Down Displays). While being associated with real features in the flight scenarios, such conformal symbols are typically based on twodimensional graphics. The aim of this work is to provide a simulator to investigate the use of threedimensional objects in the HUDs (Head Up Displays) to be installed in future cockpits. A Virtual Reality based HUD simulator has been conceived. It exploits a stereoscopic visualization screen where a double viewport has been created to overlay a computer generated HUD onto a synthetic flight scenario. The exploitation of such virtual prototyping systems in cockpit design is expected to give advantages in terms of an improved capability of following the evolution of safety and efficiency requirements.

Keywords: Cockpit design | HMI Human Machine Interface | HUD Head Up Display | Virtual reality

[31] Spadanuda A., De Crescenzio F., Fantini M., Piattoni J., Rastelli D., Santoni F., Piergentili F., Hands-on education for innovative research fields: A cubesat manufactured with rapid protyping technique, 62nd International Astronautical Congress 2011, IAC 2011, 8, 7020-7028, (2011). Abstract

Abstract: The structure of Cubesat that will be presented in the following paper was realized within the activities of Space Robotics Laboratory (SRL) and the V-Lab of the II Faculty of Engineering of Bologna University in collaboration with the Space System group of University of Rome "LA SAPIENZA". The work team that is persecuting the project proposed is composed by PHD, master and bachelor students. Several projects aimed at hands-on education are developed by the SRL including: an observatory for observation and monitoring of space debris and the creation of payloads for sounding rockets and stratospheric balloons, that are part of the ESA education program; together with the realization of the Cubesat depicted in the paper. Cubesat is a cube-shaped nano-satellite with the side of 100 mm. Despite its small size, it has a system for attitude control, a telecommunication system, a camera and a power system. Considering the size and requirements of the various systems, the organization of interior spaces was one of the major issues in the design of the structure for which it was necessary to identify innovative solutions. The Cubesat structure was realized by polymer (ABS - Acrylonitrile - Butadiene - Styrene) with the technique of "rapid prototyping" thanks to equipment provided by the V-Lab of the II Faculty of Engineering of University of Bologna. The Rapid Prototyping technique has several advantages including the quick implementation and low cost. Moreover, for the construction of a small satellite it is very useful the ability to succeed in details, sometimes difficult to achieve with the use of tools machine except with a significant increase in costs. Another important advantage is the ability to use a material with a lower density than the commonly used aluminum alloy. The structure must be able to resist at the stresses due to the launch vibrational and static loads. For this several simulations using a FEM code have been performed during the design phase, moreover a Test-Pod system in aluminum alloy was built and used to perform vibration tests for the qualification to launch with Indian PLSV launcher of the Cubesat prototype. The paper shows the detailed design of the Cubesat with the analysis of solutions to the critical points, the results of numerical simulations and the results of vibration tests carried out for the launch qualify on the Cubesat prototype. Copyright ©2010 by the International Astronautical Federation. All rights reserved.

[32] Ciocca L., Fantini M., De Crescenzio F., Corinaldesi G., Scotti R., Direct metal laser sintering (DMLS) of a customized titanium mesh for prosthetically guided bone regeneration of atrophic maxillary arches, Medical and Biological Engineering and Computing, 49(11), 1347-1352, (2011). Abstract

Abstract: This study describes a protocol for the direct manufacturing of a customized titanium mesh using CAD-CAM procedures and rapid prototyping to augment maxillary bone and minimize surgery when severe atrophy or post-oncological deformities are present. Titanium mesh and particulate autogenous plus bovine demineralised bone were planned for patient rehabilitation. Bone augmentation planning was performed using the pre-op CT data set in relation to the prosthetic demands, minimizing the bone volume to augment at the minimum necessary for implants. The containment mesh design was used to prototype the 0.6 mm thickness customized titanium mesh, by direct metal laser sintering. The levels of regenerated bone were calculated using the post-op CT data set, through comparison with the pre-op CT data set. The mean vertical height difference of the crestal bone was 2.57 mm, while the mean buccal-palatal dimension of thickness difference was 3.41 mm. All planned implants were positioned after an 8 month healing period using two-step implant surgery, and finally restored with a partial fixed prosthesis. We present a viable and reproducible method to determine the correct bone augmentation prior to implant placement and CAD-CAM to produce a customized direct laser-sintered titanium mesh that can be used for bone regeneration. © 2011 International Federation for Medical and Biological Engineering.

Keywords: Bone augmentation | CAD-CAM | Implant surgery | Rapid prototyping | Titanium mesh

[33] Ciocca L., Fantini M., De Crescenzio F., Persiani F., Scotti R., Computer-aided design and manufacturing construction of a surgical template for craniofacial implant positioning to support a definitive nasal prosthesis, Clinical Oral Implants Research, 22(8), 850-856, (2011). Abstract

Abstract: Aim: To design a surgical template to guide the insertion of craniofacial implants for nasal prosthesis retention. Materials and methods: The planning of the implant position was obtained using software for virtual surgery; the positions were transferred to a free-form computer-aided design modeling software and used to design the surgical guides. A rapid prototyping system was used to 3D-print a three-part template: a helmet to support the others, a starting guide to mark the skin before flap elevation, and a surgical guide for bone drilling. An accuracy evaluation between the planned and the placed final position of each implant was carried out by measuring the inclination of the axis of the implant (angular deviation) and the position of the apex of the implant (deviation at apex). Results: The implant in the glabella differed in angulation by 7.78°, while the two implants in the premaxilla differed by 1.86 and 4.55°, respectively. The deviation values at the apex of the implants with respect to the planned position were 1.17mm for the implant in the glabella and 2.81 and 3.39mm, respectively, for those implanted in the maxilla. Conclusions: The protocol presented in this article may represent a viable way to position craniofacial implants for supporting nasal prostheses. © 2010 John Wiley & Sons A/S.

Keywords: CAD-CAM | Craniofacial implants | Nasal prosthesis | Rapid prototyping | Virtual surgery

[34] De Crescenzio F., Fantini M., Ciocca L., Persiani F., Scotti R., Design and manufacturing of ear prosthesis by means of rapid prototyping technology, Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 225(3), 296-302, (2011). Abstract

Abstract: In this paper, the complete procedure to design and construct reusable moulds for implant-based ear prosthesis and manufacture substructures by means of a computer aided design-computer aided manufacturing (CAD-CAM) procedure and rapid prototyping (RP) technology is presented. The scan of the healthy ear, the virtual superimposition of its mirrored image on to the defective side, and the rapid manufacturing of the substructure and of the mould eliminate several steps of traditional procedures (wax, stone, try-in). Moreover, the precise design and customization of the substructure is presented, with the original and engineered shape for the retention of the silicone. The time and cost saving results of this protocol are presented together with a discussion of the main design features that make the prosthesis a stable and reproducible system to improve rehabilitation of patients with auricular defects or absence.

Keywords: CAD/CAM | facial rehabilitation | prosthetic rehabilitation | rapid prototyping | reverse engineering

[35] De Crescenzio F., Fantini M., Persiani F., Di Stefano L., Azzari P., Salti S., Augmented reality for aircraft maintenance training and operations support, IEEE Computer Graphics and Applications, 31(1), 96-101, (2011). Abstract

Abstract: Over the past decade, researchers have investigated AR as a promising candidate technology for building advanced interfaces for maintenance personnel. Nevertheless, the low usability of cumbersome hardware, the need to use markers, and the complexity of creating digital content seem to hinder AR's effective implementation in industry. This prototype system aims to demonstrate that you can implement AR to support aircraft maintenance personnel. To meet a daily inspection procedure's operational requirements, the system employs markerless pose estimation. © 2006 IEEE.

Keywords: aircraft maintenance | augmented reality | computer graphics | graphics and multimedia | human-computer interaction

[36] Ciocca L., Fantini M., de Crescenzio F., Persiani F., Scotti R., New protocol for construction of eyeglasses-supported provisional nasal prosthesis using CAD/CAM techniques, Journal of Rehabilitation Research and Development, 47(7), 595-604, (2010). Abstract

Abstract: A new protocol for making an immediate provisional eyeglasses-supported nasal prosthesis is presented that uses laser scanning, computer-aided design/computer-aided manufacturing procedures, and rapid prototyping techniques, reducing time and costs while increasing the quality of the final product. With this protocol, the eyeglasses were digitized, and the relative position of the nasal prosthesis was planned and evaluated in a virtual environment without any try-in appointment. This innovative method saves time, reduces costs, and restores the patient's aesthetic appearance after a disfiguration caused by ablation of the nasal pyramid better than conventional restoration methods. Moreover, the digital model of the designed nasal epithesis can be used to develop a definitive prosthesis anchored to osseointegrated craniofacial implants.

Keywords: CAD/CAM | Computer-aided design | Facial disfigurement | Facial rehabilitation | Immediate temporary prosthesis | Maxillofacial rehabilitation | Nasal prosthesis rapid prototyping | Reverse engineering | Silicone prosthesis | Virtual molding

[37] Ciocca L., De Crescenzio F., Fantini M., Scotti R., CAD/CAM bilateral ear prostheses construction for Treacher Collins syndrome patients using laser scanning and rapid prototyping, Computer Methods in Biomechanics and Biomedical Engineering, 13(3), 379-386, (2010). Abstract

Abstract: Ear defects in patients affected by Treacher Collins syndrome necessitate the replacement of the existing anatomic residuals of the ears with custom-made prostheses. This paper describes a multidisciplinary protocol involving both medicine and computer-aided design/computer-aided manufacturing for manufacturing ear prostheses. Using innovative prototyping technologies together with conventional silicone processing procedures, a step-by-step procedure is presented. The complete workflow includes laser scanning of the defective regions of a patient's face, the use of 3D anatomic models from an ear digital library and rapid prototyping of both substructures for bar anchoring and moulds for silicone processing. © 2010 Taylor & Francis.

Keywords: Computer-aided design | Ear prostheses | Maxillofacial rehabilitation | Rapid prototyping | Reverse engineering | Treacher Collins syndrome

[38] Ciocca L., De Crescenzio F., Fantini M., Scotti R., Rehabilitation of the nose using CAD/CAM and rapid prototyping technology after ablative surgery of squamous cell carcinoma: A pilot clinical report, International Journal of Oral and Maxillofacial Implants, 25(4), 808-812, (2010). Abstract

Abstract: Restoration of a nasal defect after ablative surgery for squamous cell carcinoma necessitates replacing the missing volume and anchoring a prosthesis to the patient’s face. This report describes the failure of plastic reconstructive surgery after ablation of a squamous cell cancer of the nose and the esthetic and functional restoration of the patient with a nasal prosthesis. The process of making an implant-supported prosthesis using digital technology, including digitized anatomic models from a "nose library," and the rapid prototyping of the mesiostructure for bar anchorage and of the mold for silicone processing are presented. © 2010 by Quintessence Publishing Co Inc.

Keywords: Computer-aided design | Computer-assisted manufacture | Maxillofacial prosthesis | Nasal prosthesis | Rapid prototyping

[39] Bagassi S., De Crescenzio F., Persiani F., Design and evaluation of a four-dimensional interface for air traffic control, Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 224(8), 937-947, (2010). Abstract

Abstract: The increasing complexity of the air traffic system is pushing towards the development of innovative and more automated tools conceived to manage it. In this scenario, an important role is played by HCI (human-computer interfaces) used by air traffic controllers and operators to visualize and interact with air traffic data. Currently, information about three-dimensional (3D) scenery is displayed with a two-dimensional representation. This paper presents the design, development, and evaluation of an innovative interface for air traffic control (ATC) based on a four-dimensional (4D) (3D space+time) visualization display. The proposed interface allows the operator to perceive all the information, including meteorological conditions, that is useful for TWR/APP (ToWeR/APProach) control in a unique 4D synthetic reconstruction of the airport area. Particular attention is dedicated to the fourth variable, time, which is a fundamental parameter in ATC. A simple and fast trajectory prediction algorithm has been implemented in order to provide the operator with an effective 'user assistance' tool in conflict detection activities. The interface has been evaluated by performing test simulations and surveys were used to collect results and useful advice for its future development.

Keywords: air traffic control | human-computer interfaces | synthetic environment | virtual reality

[40] de Crescenzio F., Miranda G., Persiani F., Bombardi T., A first implementation of an advanced 3D interface to control and supervise UAV (uninhabited aerial vehicles) missions, Presence: Teleoperators and Virtual Environments, 18(3), 171-184, (2009). Abstract

Abstract: Recent analyses on the uninhabited aerial vehicle (UAV) accidents revealed that several kinds of human-system control problems occur in current UAV missions. Therefore, a design of the man-machine interface that allows for an efficient and effective interaction between the operator and the remote vehicle becomes one of the challenges in the development of more reliable UAVs. This paper presents a first implementation of an advanced interface for UAV ground control station based on a touch screen, a 3D virtual display, and an audio feedback message generator. The touch screen is used to send high level commands to the vehicle, the 3D virtual display provides a stereoscopic and augmented visualization of the complex scenario in which the vehicle operates, and the audio feedback message generator informs the operator about any change in operational scenario. The hardware/software architecture of the interface also includes a planning algorithm and a generic vehicle model. The interface has been tested by simulating several UAV missions. The results have shown that the interface requires an adequate level of workload to command the vehicle and allows the operator to build a good level of awareness of the state of the vehicle under his or her control, as well as of the environment in which it operates. © 2009 by the Massachusetts Institute of Technology.

[41] Persiani F., De Crescenzio F., Miranda G., Bombardadi T., Fabbri M., Boscolo F., Three-dimensional obstacle avoidance strategies for uninhabited aerial systems mission planning and replanning, Journal of Aircraft, 46(3), 832-846, (2009). Abstract

Abstract: The ability to perform autonomous mission planning is considered one of the key enabling technologies for uninhabited aerial systems. Subsequently, a big effort is made in the development of algorithms capable of computing safe and efficient routes in terms of distance, time, and fuel. In this paper an innovative 3-D planning algorithm is presented. The algorithm is based on considering the uninhabited aerial systems representation of real world systems as objects moving in a virtual environment (terrain, obstacles, and no fly zones), which replicates the airspace. Original obstacle avoidance strategies have been conceived to generate mission plans that are consistent with flight rules and with the vehicle performance constraints. Simulation test results show that efficient routes are computed in a few seconds.

[42] Benazzi S., Fantini M., De Crescenzio F., Persiani F., Gruppioni G., Improving the spatial orientation of human teeth using a virtual 3D approach, Journal of Human Evolution, 56(3), 286-293, (2009). Abstract

Abstract: Since teeth are resistant to decomposition processes, they provide important and at times unique sources of information about fossil humans. Fortunately, dental remains reflect significant evolutionary changes. These changes make a very important and often exclusive contribution to the definition of new taxa or the attribution of fossil specimens to existing taxa. The traditional approach to dental morphometric analyses usually focuses on the recording of several measures of the tooth with calipers, especially the two basic crown diameters (buccolingual and mesiodistal). However, since these measures do not adequately represent the complex morphology of the tooth, 2D images and 3D digital models of dental morphology have been used. For both types of analysis, the possibility of correctly comparing homologous teeth depends on the adoption of a common orientation system. The lack of such a system makes it difficult to compare the results of different studies. Here we describe a new method for orienting teeth specifically devised for the upper and lower first molar (M1). Samples of unworn maxillary (n = 15) and mandibular (n = 15) first molars of modern humans were scanned with a Roland Picza 3D digitizer. The 3D virtual models were used to compare our new orientation method with those proposed in the literature. The new orientation system, which meets a geometric criterion, is based on three points identified on the cervical line and ensures acceptable repeatability of the spatial positioning and orientation independent of the shape and wear of the first molar under investigation. This orientation system is a first step toward the creation of a virtual set of hominid and fossil human first molars, which will allow us to make comparisons via a sophisticated and noninvasive approach. This pilot study also provides guidelines to extend the new methodology to the other types of teeth. © 2008 Elsevier Ltd. All rights reserved.

Keywords: 3D orientation systems | Morphometry | Reverse engineering | Virtual anthropology

[43] Benazzi S., Fantini M., De Crescenzio F., Mallegni G., Mallegni F., Persiani F., Gruppioni G., The face of the poet Dante Alighieri reconstructed by virtual modelling and forensic anthropology techniques, Journal of Archaeological Science, 36(2), 278-283, (2009). Abstract

Abstract: This paper describes the multi-disciplinary approach to reconstruct the face of Dante Alighieri (1265-1321). Since Dante's sepulchre will be opened in 2021, the reconstructive process is based on morphological and metric data collected on the poet's cranium during the formal identification of his remains in 1921 by the anthropologist Fabio Frassetto, as well as on the resulting plaster model. Starting from this plaster model and a morphologically compatible reference mandible, since the original mandible was never found, a 3D digital model of the complete skull was obtained by reverse engineering and virtual modelling techniques. The most important aspect in this work was the method of virtual modelling proposed for the ex novo generation of the mandible. The physical model of the skull (cranium + mandible) was then produced by means of a rapid prototyping system. This model was finally used to recreate Dante's face via traditional facial reconstruction techniques currently used in forensic anthropology. © 2008 Elsevier Ltd. All rights reserved.

Keywords: 3D digital models | Facial reconstruction | Rapid prototyping | Reverse engineering

[44] Ciocca L., De Crescenzio F., Fantini M., Scotti R., CAD/CAM and rapid prototyped scaffold construction for bone regenerative medicine and surgical transfer of virtual planning: A pilot study, Computerized Medical Imaging and Graphics, 33(1), 58-62, (2009). Abstract

Abstract: We developed a model to test new bone constructs to replace spare skeletal segments originating from new generation scaffolds for bone marrow-derived mesenchymal stem cells. Using computed tomography (CT) data, scaffolds were defined using computer-aided design/computer-aided manufacturing (CAD/CAM) for rapid prototyping by three-dimensional (3D) printing. A bone defect was created in pig mandible ramus by condyle resection for CT and CAD/CAM elaboration of bone volume for cutting and scaffold restoration. The protocol produced a perfect-fitting bone substitute model for rapid prototyped hydroxyapatite (HA) scaffolds. A surgical guide system was developed to accurately reproduce virtually planned bone sectioning procedures in animal models to obtain a perfect fit during surgery. © 2008 Elsevier Ltd. All rights reserved.

Keywords: Bone regeneration | CAD-CAM | Maxillofacial prosthesis | Rapid prototyping | Scaffold

[45] Bagassi S., De Crescenzio F., Persiani F., Design and evaluation of a 4D interface for ATC, ICAS Secretariat - 26th Congress of International Council of the Aeronautical Sciences 2008, ICAS 2008, 1, 3987-3993, (2008). Abstract

Abstract: The increasing complexity of Air Traffic System is pushing toward the development of innovative and more automated tools conceived to manage it. In this scenario an important role is assumed by HCI (Human Computer Interfaces) used by air traffic controllers and operators to visualize and interact with air traffic data. Currently, information about 3D scenery are displayed with a two-dimensional representation. This paper presents the design, development and evaluation of an innovative interface for ATC (Air Traffic Control) based on a 4D (3D space + time) visualization display. The proposed interface allows the operator to perceive all the information, included meteorological conditions, useful for TWR/APP (ToWeR/APProach) control in a unique 4D synthetic reconstruction of the airport area. A particular attention is dedicated to the fourth variable, time, which is a fundamental parameter in ATC. A simple and fast trajectory prediction algorithm has been implemented in order to provide the operator with an effective "user assistance" tool in conflict detection activities. The interface has been evaluated performing test simulations and collecting results and useful advices for future developments by means of questionnaires.

Keywords: ATC | HCI | Synthetic environment | Virtual reality

[46] De Crescenzio F., Miranda G., Persiani F., Bombardi T., 3D obstacle avoidance strategies for uas (unihabited aerial systems) mission planning and re-planning, 8th AIAA Aviation Technology, Integration and Operations (ATIO) Conference, (2008). Abstract

Abstract: The interest of both the academics and industrials for the UASs (Uninhabited Aerial Systems) has been significantly growing for the last ten years. Technological developments in their design are opening the way for their exploitation in a wide range of applications. Nevertheless, the expected benefits are not yet fully exploited due to the still significant number of accidents. Several researches have demonstrated that the absence of vehicle decisional capacity is among the most important causes of such accidents. One of the proposed solutions is to increase the vehicle ability to perform autonomous mission planning. In this paper a planning algorithm for UASs mission is presented. Such algorithm has been designed following an heuristic approach in order to rapidly provide a robust solution to mission planning problem in evolving scenario. Original obstacle avoidance strategies have been conceived in order to generate mission plans which are consistent with flight rules and with the vehicle performance constraints. Simulation test results show that very efficient routes are computed in a few seconds. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.

[47] Fantini M., De Crescenzio F., Persiani F., Benazzi S., Gruppioni G., 3D restitution, restoration and prototyping of a medieval damaged skull, Rapid Prototyping Journal, 14(5), 318-324, (2008). Abstract

Abstract: Purpose - The purpose of this paper is to describe the method of virtually and physically reconstructing the missing part of a badly damaged medieval skull by means of reverse engineering, computer-aided design (CAD) and rapid prototyping (RP) techniques. Design/methodology/approach - Laser scanning data were used to create the 3D model of the damaged skull. Starting from this digital model, a virtual reconstruction of the missing part of the skull, based on the ideal symmetry with respect to the mid-sagittal plane, was achieved in a CAD environment. Finally, the custom-designed model was directly fabricated by means of the RP process. Findings - The result shows that the designed missing part of the skull fits very well with the existing skeletal remains. The final physical assembly of the prototyped element on the damaged skull was tested, restoring it to its whole original shape. Research limitations/implications - The entire process was time-consuming and may be applied just to the most representative skeletal remains. Practical implications - The method allows accurate fabrication of the missing part of the skull to be joined with the original skeletal remains. The advantage of using this technique is that the joining operation can be carried out without any need of supplementary connecting material, such as glue or plaster, to fix together the two parts. Originality/value - The reversible and non-invasive method improves the restoration process, reduces the risk of damage to the skeletal structure and allows reversion to the original repair as it was before. © Emerald Group Publishing Limited.

Keywords: Bones | Computer aided design | Rapid prototyping

[48] Bagassi S., De Crescenzio F., Persiani F., Design and development of an ATC distributed training system, 8th AIAA Aviation Technology, Integration and Operations (ATIO) Conference, (2008). Abstract

Abstract: The current development of an "European Air Traffic Management Network" is emphasizing the role of training activities for controllers. The most advanced training centers are equipped with tower, radar and flight simulators in which all the phases of air traffic control process (including the pilot's condition) can be reproduced with an high degree of realism. Therefore, these systems mostly operate stand alone not exploiting the challenge of connecting single platforms in a unique distributed environment. In this paper a distributed training system is designed and experimented. It includes traffic simulation, flight simulation and real time voice communications. Air traffic in approach, landing and ground operations is simulated in a virtual air field and displayed on a table-top interface. One of the flight animations is performed in real time connecting the table-top with a FFS (Fixed Flight Simulator). The other planes which animate the environment follow recorded paths. Once the simulation is performed training activities continue using an off-line virtual debriefing tool of the simulated ATC process. The whole system aims at providing the controller with the awareness about the tasks performed by pilots and their consequences on the ATC scenario development. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.

Keywords: ATC | Distributed simulation | Synthetic environments | Virtual reality

[49] De Crescenzio F., Miranda G., Persiani F., Bombardi T., Advanced interface for UAV (Unmanned Aerial Vehicle) ground control station, Collection of Technical Papers - 2007 AIAA Modeling and Simulation Technologies Conference, 1, 486-494, (2007). Abstract

Abstract: The research presented in this paper focuses on an advanced interface in a UAV Ground Control Station whose aim is to guarantee a high level of situation awareness and a low level of workload in the control and supervision of unmanned vehicles. The interface is based on a touch screen-used to command the UAV by means of high level commands-and a 3D Virtual Display which provides a stereoscopic and augmented visualization of the complex scenario in which the vehicle operates. Good levels of situation awareness are also guaranteed by an audio feedback that informs the operator about any change in operational situation, as well as when the mission objectives have been accomplished. Test results have revealed that this interface provides the operator with good sense of presence and enhanced awareness of the mission scenario and the aircraft under his control.