Uberti Stefano

Ricercatore tempo indeterminato


Università degli Studi di Brescia
stefano.uberti@unibs.it

Sito istituzionale
SCOPUS ID: 55229611600
Orcid: 0000-0002-4831-7520



Pubblicazioni scientifiche

[1] Paderno D., Bodini I., Uberti S., Villa V., Baronio G., Methodology for Online Assessment of Technical Drawing Skills of Industrial Engineering Students, Lecture Notes in Mechanical Engineering, 1598-1609, (2023). Abstract
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Abstract: Due to the pandemic, there has been a shift from conducting paper-based in-person exams to conducting online exams. To still be able to evaluate students, a closed-ended test was implemented to verify the skills acquired by the exam candidates. We have developed on Moodle platform an online test called Technical Drawing Test (TDT2) based on graphic questions with closed answers both single and multiple, replacing the open-ended graphic questions of the previous in-person paper exam mode and with the same contents. This article aims to show the method by which the types of exercises were chosen according to the skills to be tested and to present the first results obtained, with the goal of verifying that the new test is equivalent to the old paper-based open-ended test in its ability to test candidates’ skills. The reliability of the TDT2 is quantified through two statistical synthetic indexes calculated by the Moodle platform and comparing the results of the online TDT2 with the results of the paper-based in-person exams.

Keywords: Engineering education | Moodle | Technical drawing | Testing methods

[2] Pullia M.G., Benedetto E., Dassa L., De Matteis E., Donetti M., Felcini E., Frisella G., Karppinen M., Kurfürst C., Mariotto S., Mereghetti A., Mirandola A., Pella A., Perini D., Piacentini L., Pivi M.T.F., Prioli M., Ratkus A., Rossi L., Sabbatini L., Savazzi S., Stock M., Tommasini D., Torims T., Uberti S., Vannozzi A., Vilcans J., Vretenar M., Explorative studies of an innovative superconducting gantry, Journal of Physics: Conference Series, 2420(1), (2023). Abstract
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Abstract: The Heavy Ion Therapy Research Integration plus (HITRIplus) is an European project that aims to integrate and propel research and technologies related to cancer treatment with heavy ion beams. Among the ambitious goals of the project, a specific work package includes the design of a gantry for carbon ions, based on superconducting magnets. The first milestone to achieve is the choice of the fundamental gantry parameters, namely the beam optics layout, the superconducting magnet technology, and the main user requirements. Starting from a reference 3 T design, the collaboration widely explored dozens of possible gantry configurations at 4 T, aiming to find the best compromise in terms of footprint, capital cost, and required R&D. We present here a summary of these configurations, underlying the initial correlation between the beam optics, the mechanics and the main superconducting dipoles design: the bending field (up to 4 T), combined function features (integrated quadrupoles), magnet aperture (up to 90 mm), and angular length (30° – 45°). The resulting main parameters are then listed, compared, and used to drive the choice of the best gantry layout to be developed in HITRIplus.

Keywords: Heavy ions | Ion beams

[3] Paderno D., Bodini I., Baronio G., Uberti S., Montesano L., Tonoli S., Pola A., Villa V., Design and Validation of a Block-on-Ring Test Bench, Lecture Notes in Mechanical Engineering, 729-738, (2022). Abstract
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Abstract: According to the activities carried out within the Proof of Concept laboratory, a machine for block-on-ring wear tests was designed and realized. Consistent with the approach of the laboratory, the machine was developed with particular attention to the requirements of reliability, simplicity, as well as easy and fast production starting from existing devices integrated with ad-hoc made parts by the department equipment. The experimental campaign was performed according to ASTM G99 and ASTM G77. The results obtained on commercial pin-on-disc device and on the realized block-on-ring machine, showed a good agreement, validating the proposed solution. This appears particularly effective also based on an economic and technical comparison with commercial equipment complying with the same standard.

Keywords: Design and test | Design methods | Machine design

[4] Bodini I., Bannò M., Paderno D., Baronio G., Uberti S., Villa V., Students Creativity Assessment Through Gray’s “Forward Flow” Tool: A Preliminary Study, Lecture Notes in Mechanical Engineering, 879-888, (2022). Abstract
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Abstract: The promotion of creativity in education is intended to address many of the political challenges and goals for the development of a country, but among all of them the role of creativity in technology and economics is seen as crucial in helping nations to achieve higher employment, better economic performance and to cope with global competition. This study, currently in its preliminary phase, aims to compare the creativity levels of first-year students at a medium-sized Italian university. The degree courses in Engineering Management, Mechanical Engineering, Law and Motor Sciences were analyzed. In this analysis, students’ creativity is measured with the “Forward Flow” test by Gray et al. This test implements a new metric that uses latent semantic analysis to measure the evolution of thoughts over time. Operationally, students are asked to produce a sequence of semantically related words from a given initial word. Latent semantic analysis calculates the semantic distance between words by examining the frequency with which they appear together in a very large collection of documents. Studies conducted on the test, found in the literature, reveal that Forward Flow can predict the creativity of college students. According to these studies, even that membership in real-world creative groups (e.g. professional actors or entrepreneurs) is statistically predicted by scores on the Forward Flow test, even when controlling for divergent thinking.

Keywords: Creativity | Engineering education

[5] Bodini I., Baronio G., Paderno D., Villa V., Martinelli P., Frizza R., Balsamo A., Uberti S., Proposal for a Method for Advanced Search of Information and Standards in the Field of Geometrical Product Specification, Lecture Notes in Mechanical Engineering, 269-276, (2022). Abstract
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Abstract: The Geometrical Product Specification (GPS) is one of the most powerful tools available to link the “perfect” geometrical world of the models to the imperfect world of manufactured parts and assemblies. GPS aims to be an unambiguous common language between designers, process engineers, and Coordinate Measuring Machines operators (CMM) in the ISO (International Organization for Standardization) environment. GPS standards are 150 and further 26 are under development. The need to have a tool to search through the standards, to optimize the work of the designer and to minimize the design, production and control costs is great. A database and the structure for a search engine, called GPS Navigator, has been studied and developed, and the requirements for the following coding phase have also been defined, in order to realize a powerful, efficient, fast, robust and rigorous tool to navigate through the GPS standards. Final aim of this tool is to help and guide the designer to quickly consult the correct standard or the most appropriate set of standards.

Keywords: Advanced search criteria | Database | Design methods | Geometrical product specifications (GPS)

[6] Beltrami D., Iora P., Uberti S., The Potential Role of Natural Gas Vehicles in the Reduction of GHG Emissions in the Italian Private Transportation Framework, SAE Technical Papers, (2022). Abstract
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Abstract: This paper investigates the possibility to reduce the emissions of CO2 in the Italian passenger transportation sector by increasing the share of internal combustion engine vehicles fed by natural gas. In fact, from an environmental point of view, natural gas is a better choice in comparison with traditional oil-based fuels, as it yields less CO2, NOx, and PM emissions per kilometer, than classical gasoline and diesel engines, due to its intrinsic characteristics. For this reason, natural gas vehicles can effectively contribute to the energy transition, especially in the short-medium term, as it can be in the energy production sector. Nonetheless, Italian institutions address most of the eco-incentives' mechanism to promote hybrid and electric passenger vehicles, irrespective of the different types of fuel for the internal combustion engine. In this paper, a technical overview of the different available propulsion systems adopted in commercial vehicles is first presented. Then, the Italian passenger vehicle market is analyzed to have a clear picture of the Italian private transportation framework, as well as to provide a sound basis to evaluate to what extent the natural gas vehicles can contribute to the reduction of greenhouse gas emissions (GHG). We show that with the eco-incentives' mechanism of the two-year period 2020-2021, which provides a maximum amount of €6500 specifically to electric vehicles, the resulting overall cost of the avoided CO2 is about 975 €/tCO2 for an average vehicle lifespan of 10 years. However, addressing natural gas vehicles in place of electric ones with an incentive amount of €1000, this cost-benefit ratio could increase of about 14%.

Keywords: Carbon dioxide | Combustion | Commercial vehicles | Cost benefit analysis | Gas emissions | Greenhouse gases | Internal combustion engines | Natural gas vehicles | Propulsion

[7] Perini D., Dassa L., Piacentini L., Uberti S., Preliminary design of the support structure for a rotating carbon-ion transfer line for medical applications, Instruments, 5(4), (2021). Abstract
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Abstract: The development of new bent superconducting magnets together with the optimization of the support structure open the way to a considerable reduction in the weight and complexity of rotating gantries for medical applications. The magnets, which define the transfer line to deliver carbon ions to the patients from different angles, are supported by a rotating structure that should be as rigid and as lightweight as possible. Relative displacements of the magnets due to deformations cause incorrect beam position and consequent errors in hitting the target tissues. This paper describes a possible rotating structure which is considerably lighter than the previous designs. A method to compensate part of the deformation by complementary rotations of the driving motor is proposed. The influence of the construction tolerances and deformations of the supports is also analyzed and alignment and adjustment possibilities are discussed.

Keywords: Curved magnets | Gantry for medical applications | Ion therapy

[8] Baronio G., Bodini I., Motyl B., Uberti S., Prototyping, testing, and redesign of a three-wheel trekking wheelchair for accessible tourism applications, Applied Sciences (Switzerland), 11(20), (2021). Abstract
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Abstract: This work is part of the project called “Gölem project”, started in 2017, about special devices developed to enable the so-called Accessible Tourism. This project aims to design and develop a trekking wheelchair for people with impaired mobility. After an initial phase of design and prototyping, the testing phase has now begun. The objective is to validate several aspects of the design, concerning basic kinematics and dynamics, passenger comfort and physical effort of the carriers. This paper describes the development of qualitative tests for drivability and balance validation of this first prototype. At this stage, a list of features to be investigated was made, suitable trekking paths were chosen, and qualitative experimental field tests were performed. Then, the design of the prototype was modified according to these first experimental results, to improve the wheelchair characteristics. The prototype is now undergoing the modification phase, then further testing will be performed with the use of specific instrumental devices to evaluate the wheelchair itself and to perform the kinematic, dynamical, and comfort characterization.

Keywords: Accessible tourism | Assistive technologies | Design methods | Disabled people | Experimental testing | Hiking wheelchair | Trekking wheelchair | User-centered design

[9] Beltrami D., Iora P., Tribioli L., Uberti S., Electrification of compact off-highway vehicles—overview of the current state of the art and trends, Energies, 14(17), (2021). Abstract
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Abstract: Electrified vehicles have undergone great evolution during the last decade because of the increasing attention paid on environmental sustainability, greenhouse gas emissions and air pollution. Emission regulations are becoming increasingly tight, and governments have been allocating multiple funds to facilitate the spreading of the so-called green mobility. In this context, steering towards electrified solutions not only for passenger vehicles, but also for compact off-highway vehicles extensively employed, for instance, on construction sites located in urban areas, warehouses, and greenhouses, is essential even if seldom considered. Moreover, the electrification of compact offhighway machinery may allow manufacturers to increase their expertise in and lower the costs of these alternative solutions, while gathering useful data to be applied in bigger and more remunerative off-highway vehicles. In fact, while electric automobiles are as of now real alternatives for buyers, off-highway vehicles, regardless of the application, are mostly in the research and experimental phase, with few of them already on the market. This delay, in comparison with the passenger automotive industry, is caused by different factors, mostly related to the different tasks of off-highway vehicles in terms of duty cycles, productivity performance parameters and user acceptability. The aim of this paper is to give an overview of the many aspects of the electrification of compact off-highway vehicles, to highlight the key differences between on-highway and off-highway vehicles and to summarize in a single source of information the multiple solutions investigated by researchers and manufacturers.

Keywords: Battery electric | Compact off-highway vehicles | Electrification | Green mobility

[10] Mazzù A., Uberti S., Bodini I., Paderno D., Danesi A., Dynamical behaviour of Bronze Age war chariots, Journal of Archaeological Science: Reports, 36, (2021). Abstract
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Abstract: The dynamical behaviour of the Bronze Age war chariots was studied, considering the different assembly solutions that were found in evidences and pictures. In particular, the chariots with the axle in rear position, typical of Near-East and Egypt, were compared with the European ones, which generally had the axle in central position under the chariot cockpit. Furthermore, the role of the floor, usually realized in woven leather or other organic fibres, was investigated. Dynamical finite element and multibody simulation software was used for studying the behaviour of the chariots in occasional overloading events, such as bumps or curves. An experimental device was set up for studying the difference of the response of a woven floor with respect to a wooden one. Finally, a finite element frequency response analysis was carried out to investigate the behaviour in full run over a rough ground. The results showed that position of the axle did not significantly influence the response of the chariot to occasional overloads. On the contrary, it had a strong influence on the stability of the passengers: rear axle chariots were much more effective in cutting the vibrations transmitted to the passengers when running at high speed. This effect was amplified by an increased floor flexibility, which was achieved with a woven floor. These findings could explain the diffusion of the rear-axle chariots in the Near-East and Egypt, where the chariotry was the most important part of the armies: indeed, the effectiveness in cutting the vibrations at high speed should be a crucial factor for ensuring the required precision to the transported archers. On the contrary, the likely marginal role of the chariots in the European armies could lead to the diffusion of central axle model, which ensured a lower burden on the draught horses.

Keywords: Bronze age | Chariots | Dynamics | Stability | Vibrations | War

[11] Talluri L., Niknam P., Copeta A., Amato M., Iora P., Uberti S., Invernizzi C., Di Marcoberardino G., Pacini L., Manfrida G., Fiaschi D., A revised Tesla Turbine concept for 2-phase applications, E3S Web of Conferences, 238, (2021). Abstract
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Abstract: The Tesla turbine is an original expander working on the principle of torque transmission by wall shear stress. The principle - demonstrated for air expanders at lab scale has some attractive features when applied to two-phase expanders: it is suitable for handling limited flow rates (as is the case for machines in the range from 500W to 5 kW), it can be developed to a reasonable size (rotor of 0.1 to 0.25 m diameters), with acceptable rotational speeds (which range from 500 to 10000 rpm). The original concept was revisited, designing it for two-phase operation and considering not only the rotor configuration but the whole machine. The flow model was developed using complete real fluid assumptions including several new concepts such as bladed channels for the stator, labyrinth seals, and a rotating diffuser. Preliminary design sketches are presented, and results discussed and evaluated.

[12] Carlsson U., Uberti S., Piana E.A., Experimental investigation on the acoustic behaviour of a small tractor cabin, "Advances in Acoustics, Noise and Vibration - 2021" Proceedings of the 27th International Congress on Sound and Vibration, ICSV 2021, (2021). Abstract
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Abstract: The quality and acoustic comfort of agricultural tractor cabins are nowadays highly valued by the market. For this reason, tractor manufacturers are more and more interested in improving the behaviour of their vehicles also from an acoustics point of view. A tractor cabin is an unusual environment, with a space mainly developed in the vertical direction, characterised by a relatively small volume of air and surrounded by windows, which can be considered as large reflecting surfaces. This feature causes strong standing waves that, when coupled with an acoustic source, can generate high sound pressure levels resulting in reduced comfort for the driver. This paper investigates, through measurements and simulations, the low frequency acoustic behaviour of a small tractor cabin. The technique adopted for the measurements is based on a multiple transfer function analysis. Measured frequency response functions are processed for the cabin's acoustic mode parameters. The results of the experiments are validated through a finite-element model allowing the reconstruction of the sound pressure contours inside the volume and further analyses.

Keywords: Finite element | Sound absorption | Standing waves | Tractor cabin | Transfer function

[13] Mazzù A., Uberti S., Bodini I., Dynamical and structural analysis of a Bronze Age war chariot, IOP Conference Series: Materials Science and Engineering, 949(1), (2020). Abstract
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Abstract: The introduction of two-wheel chariots, pulled by horses, was a key technological innovation in the Bronze Age. Archaeological evidences, found in Northern Africa, Europe and Asia, allowed identifying various chariot typologies and understanding their main features. However, many questions about the function of single pieces and the behavior of the vehicles are still open. In a previous work, a war chariot wheel, found in northern Italy and known as the “Mercurago wheel”, was studied with an engineering approach. In this paper, the whole vehicle, to which the wheel was hypothesized to belong, was studied. In particular, two chariot typologies, differing mainly for the axle position, were analyzed. The stiffness of the various chariot parts were characterized by means of static finite element analyses. These data were subsequently used as input parameters in running multibody dynamics simulations. Finite element dynamical simulations were carried out as well. The analyses results allowed determining the crucial effect of some parts, particularly the cockpit floor, in favoring the passenger stability in dangerous conditions, such as bumping. The effect of the axle position on the passenger and wheel trajectory were evaluated as well.

[14] Uberti S., Azzini G., Beltrami D., Tribioli L., Iora P., Modelling of a 15-kW Electric Utility Vehicle and Range Assessment through Driving Cycle Analysis Based on GPS Experimental Data, SAE Technical Papers, (2020). Abstract
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Abstract: The electrification of utility vehicles represents a promising solution to reduce the emissions in the urban context. Differently from traditional vehicles, they operate intermittently and generally follow routine driving cycles. In this paper, we model a 15-kW electric utility vehicle, adopting a backward-looking approach, widely used in literature to estimate the range of electric cars. The model requires a limited number of data, either supplied by the vehicle manufacturer or found in literature, as in case of the induction motor/generator efficiency and of the battery Peukert coefficient. The model can be used to assess the possibility of the vehicle to complete an assigned mission, as well as to optimize the vehicle's design and architecture. The model is validated on GPS data obtained through an experimental campaign where the electric utility vehicle was driven to depletion considering different routes, including the effect of slopes. A satisfactory correspondence with the experimental data was observed with maximum difference in the simulated average energy consumption lower than about 8%. Results of the simulations show that the range of the electric utility vehicle is about 110 km on urban flat cycle while it significantly reduces when slopes are included in portions of the routes.

[15] Baronio G., Bodini I., Paderno D., Uberti S., Villa V., Objective Evaluation of Geometrical Product Specification/Geometrical Dimensioning and Tolerancing Basic Skills, Lecture Notes in Mechanical Engineering, 305-312, (2020). Abstract
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Abstract: The aim of this work is to study methods and criteria to objectively evaluate Geometrical Product Specification (GPS) and Geometrical Dimensioning and tolerances (GD&T) basic skills of engineering students. To do so, it is important to define who is the examiner, what is the topic of the exam, how to examine, when and why. In particular, for what concerns the topics, knowledge, competences, skills, concepts and abilities should be assessed. Basic knowledge is the easier topic to evaluate in an objective and reliable way, for example using closed-ended questions, but skills like creativity are difficult to measure. Following the principles of Bloom’s taxonomy, a technical drawing evaluation grid has been developed and used by the authors. The grid has eight learning levels, and target knowledge, competences, and skills have been defined for each learning level, then specific tests to verify the target for each level have been studied and developed. In this paper some examples of application of the grid are described and some preliminary results and considerations are reported. In particular, using an objective closed-ended question test, which rigorously assesses the basic levels of the grid, “residual” students decrease in number, and the students increase in number, the test is cost-effective.

Keywords: Bloom’s taxonomy | Engineering education | Engineering students evaluation | GPS/GD&T | Technical drawing

[16] Uberti S., Copeta A., Development of an Exhaust System for Agricultural Tractors, Lecture Notes in Mechanical Engineering, 387-399, (2020). Abstract
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Abstract: The main sources of sound emitted by vehicles are the engine and the rolling noise produced by the tires. In case agricultural tractors are considered, the engine and the transmission are responsible of the main emissions since they often work in the fields on soft ground at low speeds. This work focuses on the combined acoustic and mechanical development of a new exhaust system for an existing agricultural tractor, with the aim of providing a product with improved acoustic performances and a neater design. The host vehicle is equipped with a 300 hp diesel engine which can be particularly noisy at low rpm, with a further constraint being the “under the bonnet” available volume to fit the system into. The existing exhaust system is the baseline for the engineering process. The acoustic design is carried out by a 1D simulation software based on an electro-acoustic analogy, while the design modelling is performed by using Solidworks® 3D CAD. After the design stage a prototype has been manufactured and tested at the MWL/KTH laboratory. The engineering process gave the product a cleaner design and allowed to identify feasible solutions ensuring increased sound attenuation performances.

[17] Iora P., Cassago A., Invernizzi C., Copeta A., Di Marcoberardino G., Uberti S., Fiaschi D., Talluri L., Tribioli L., Assessment of Energy Consumption and Range in Electric Vehicles with High Efficiency HVAC Systems Based on the Tesla Expander, SAE Technical Papers, (2019). Abstract
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Abstract: Battery electric vehicles (BEVs) are considered one of the most promising solution to improve the sustainability of the transportation sector aiming at a progressive reduction of the dependence on fossil fuels and the associated local pollutants and CO2 emissions. Presently, the major technological obstacle to a large scale diffusion of BEVs, is the fairly low range, typically less than 300 km, as compared to classical gasoline and diesel engines. This limit becomes even more critical if the electric vehicle is operated in severe weather conditions, due to the additional energy consumption required by the cabin heating, ventilating, and air-conditioning (HVAC). The adoption of vapor-compression cycle, either in heat pump or refrigerator configuration, represents the state-of-the-art technology for HVAC systems in vehicles. Such devices typically employ an expansion valve to abruptly reduce the pressure causing the flash evaporation of the working fluid. This component, although necessary to provide the cooling effect, is also responsible of a significant exergy loss, which reduces the efficiency of the thermodynamic cycle. In this paper we study the possible benefits in terms of energy saving and consequent increase of the driving range, that can be obtained in electric vehicles that adopt a high efficiency HVAC system, where the Tesla turbine replaces the classical expansion valve in order to recover part of the exergy typically lost by the working fluid in the expansion phase. First, an off-design thermodynamic model was developed to assess the performance of the proposed HVAC system as function of the ambient temperature. Then, the calculated COP curves were implemented in an in-house Matlab code based on Nissan Leaf design data. Simulations are carried out considering various reference driving cycles showing that this solution may result in a potential increase of the electric vehicle range up to 5%.

[18] Baronio G., Bodini I., Copeta A., Dassa L., Grassi B., Metraglia R., Motyl B., Paderno D., Uberti S., Villa V., Integrated approach to the innovation of technical drawing teaching methods, Lecture Notes in Mechanical Engineering, 705-713, (2019). Abstract
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Abstract: Motivations for the research activity on teaching methods could be listed as: Institutional duty; reduction of evaluation costs; establishing convenient relationships between teaching, research and publications; developing educational programs for non-academic learners; consolidating learning outcomes. Teaching is the most commonly recognized mission of university, and evaluation has a cost in terms of time and resources, both precious: At least a portion of the exam, the one concerning factual knowledge, may be done in economies of scale. The most of basic technical drawing teachers works with very large classes and faces the dilemma of choosing what to sacrifice among teaching quality, research projects, earning opportunities, personal interests, etc. A possible partial solution to such a dilemma is to work on projects aimed at teaching innovation, so to create convenient relationships between teaching, research and publications. A further consequence of lowering the cost of evaluation would be to make cost effective a more tests and, consequently, to achieve less temporary learning. Not just simple notions but also skills and abilities. In this paper the authors presents a structured synthesis of teaching innovation experiences of a ten-year span. Over time, they were divided into four integrated directions: definition of prerequisites, expected outcome evaluation grids; authentic assessment methods; teaching and learning tools.

Keywords: Design methods | Engineering education | Learning techniques | Technical drawing

[19] Piana E.A., Uberti S., Copeta A., Motyl B., Baronio G., An integrated acoustic–mechanical development method for off-road motorcycle silencers: from design to sound quality test, International Journal on Interactive Design and Manufacturing, 12(3), 1139-1153, (2018). Abstract
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Abstract: Vehicle noise is one of the main sources of complaints because it is widespread and active in almost all environments, from urban areas to rural context. The present work aims to describe a practical procedure to design silencers for off-road motorcycles so that, once produced, they are lightweight, do not affect the engine performances and cut noise emissions to a sustainable limit. The required noise reduction, usually around 35–40 dB, can be achieved only by carefully designing the exhaust system. The first part of the paper provides the theoretical background of noise propagation in ducts, describes the main attenuation devices as tools the designer can use in the development process and outlines the workflow. In the second part, a case study of silencer optimization is presented: the noise emitted by a real off-road motorcycle is characterized and, once the sound pressure level and the mass flow generated by the engine are known, a silencer fulfilling noise attenuation, size and pressure drop requirements is designed, 3D-modeled and rendered. The outcome of the acoustic design process can be used to perform virtual sound quality tests, which can be of interest for manufacturers to catch the attention of passionate users.

Keywords: Acoustic design | Design methods | Mechanical design | Off-road motorcycle silencer | Virtual modeling | Virtual sound testing

[20] Mazzu A., Gambari F.M., Uberti S., Bodini I., Pasinetti S., Sansoni G., An engineering study of a Bronze Age war chariot, IOP Conference Series: Materials Science and Engineering, 364(1), (2018). Abstract
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Abstract: The Bronze Age crossbar wheel found in the XIX century in Mercurago (Italy) is an amazing example of the technical innovations stimulated by the diffusion of horse draught war chariots in Europe across the third and second millennium b.C. In this paper the tools of modern engineering were used to study the structural issues concerning the wheel and the chariot it should be attached to. In particular, the laser-scanner technology and finite element analysis were used for investigating the dimensional, shape and assembly issues of the wheel, as well as for assessing its structural integrity under operating conditions. The role of the inserted nave, which could be similar to modern bushings, was particularly emphasised, as it is a very innovative solution for that time. The performance of a war chariot equipped by this wheel was studied by means of a vehicle dynamics simulation software, hypothesizing two different chariot structures on the basis of Armenian and Egyptian evidences respectively. The former is probably more similar to the chariot to whom the Mercurago wheel was attached; the latter is technically much more advanced. The results of the analysis allowed obtaining important information about the chariot stability, reliability and structural integrity.

[21] Uberti S., Copeta A., Baronio G., Motyl B., An eco-innovation and technical contaminated approach for designing a low environmental impact off-road motorcycle, International Journal on Interactive Design and Manufacturing, 12(1), 281-295, (2018). Abstract
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Abstract: What does it make some sports such as off-road motorcycle to be perceived as non-environmentally-friendly? Are the activities themselves or the actual and/or traditional way of their fulfillment? How is it possible to make them more environmentally sustainable without giving up the fun? This paper aims to give an answer to these questions, analyzing the case of off-road motorcycling. It is clear that some of negative consequences of such sport are due to the bad behavior and scarce ecological awareness of its practitioners, while it is often neglected that other aspects are related to the present characteristics of its means: the motorcycles. The present work, starting with the analyses of the environmental damages related to this sport, tries to give an answer focusing on the technical aspects of actual motorcycles that can be related to such damages. In particular, the authors propose the application of an integrated eco-innovation and technical contaminated approach for the design and development of a new concept of off-road motorcycle to meet the requirements of low environmental impact and light weight of the vehicle, while maintaining the pleasure of riding in the nature.

Keywords: Eco-innovation | Environmental impact | LCA | Off-road motorcycle | Rear suspensions | Terramechanics

[22] Baronio G., Copeta A., Motyl B., Uberti S., Gölem project: Concept and design of a trekking/hiking wheelchair, Advances in Mechanical Engineering, 9(11), (2017). Abstract
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Abstract: This work concerns the growing interest in accessible tourism and describes the early stages of development of Gölem project. In particular, it takes into account accompanying activities of disabled people in mountain areas. Although literature and market analysis highlight the presence of different technical solutions used for the movement of disabled persons on rough terrains, there are only a couple of solutions based on the help of guides: Joëlette© and TrailRider©. Even if the use of these devices is generally satisfactory, our analysis has highlighted the presence of some limitations such as the difficulty of maintaining the lateral balance of the devices (which involves a considerable physical effort for the guides) and their reduced comfort for the passenger. This article describes the activities developed within the Gölem project. Its main goals are to design and to test an improved model of trekking/hiking wheelchair taking into account passengers comfort and better functionality of the device. At this moment, the design and modeling phases with the definition of dynamic parameters and of the suspension system of the device have been completed. The prototype implementation phase is in progress. Future activities will provide validation and field testing of the new solution with users.

Keywords: Accessible tourism | Comfort design | Disabled people | Mountain | Suspension system design | Trekking/hiking wheelchair

[23] Benini C., Gadola M., Chindamo D., Uberti S., Marchesin F.P., Barbosa R.S., The influence of suspension components friction on race car vertical dynamics, Vehicle System Dynamics, 55(3), 338-350, (2017). Abstract
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Abstract: This work analyses the effect of friction in suspension components on a race car vertical dynamics. It is a matter of fact that race cars aim at maximising their performance, focusing the attention mostly on aerodynamics and suspension tuning: suspension vertical and rolling stiffness and damping are parameters to be taken into account for an optimal setup. Furthermore, friction in suspension components must not be ignored. After a test session carried out with a F4 on a Four Poster rig, friction was detected on the front suspension. The real data gathered allow the validation of an analytical model with friction, confirming that its influence is relevant for low frequency values closed to the car pitch natural frequency. Finally, some setup proposals are presented to describe what should be done on actual race cars in order to correct vehicle behaviour when friction occurs.

Keywords: friction | Passive suspension | suspension system | validation

[24] Motyl B., Baronio G., Uberti S., Speranza D., Filippi S., How will Change the Future Engineers’ Skills in the Industry 4.0 Framework? A Questionnaire Survey, Procedia Manufacturing, 11, 1501-1509, (2017). Abstract
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Abstract: Industry 4.0 represents one of the most challenging themes for engineering design and also for engineering education. At this moment there are few studies in the field of engineering teaching that aim to investigate how the educational needs of students and of the industrial workforce are changing. On this basis, this research would like to investigate which are the necessary skills and expertise young engineers require to be ready for the Industry 4.0 framework. In particular, a questionnaire was developed to analyze this situation. It has been administered to students enrolled in the first and second year of the engineering undergraduate degrees held in three Italian universities: Brescia, Udine and Cassino. During two different academics years, a total of 463 students participated to the survey. The questions were aimed to investigate some key issues of Industry 4.0, and the students’ digital belief and behaviors at their entrance in the university education system. The collected answers provided a picture of the actual situation in these three universities with some relevant considerations about engineering education. So, the fundamental question that authors want to answer is “Are the Italian engineering students effectively ready for Industry 4.0 or do we still work on it?”

Keywords: digital skills | Engineering Education | Industry 4.0 | questionnaire | student skills

[25] Gritti G., Peverada F., Orlandi S., Gadola M., Uberti S., Chindamo D., Romano M., Olivi A., Mechanical steering gear internal friction: Effects on the drive feel and development of an analytic experimental model for its prediction, Lecture Notes in Mechanical Engineering, 0, 341-351, (2017). Abstract
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Abstract: The automotive steering system inevitably presents internal friction that affects its response. This is why internal friction phenomena are carefully monitored either by OEMs and by vehicle manufacturers. An algorithm to predict the mechanical efficiency and the internal friction of a steering gear system has been developed by the ZF-TRW Technical Centre of Gardone Val Trompia and the University of Brescia, Italy. It is focused on mechanical steering gear of the rack and pinion type. The main contributions to the overall friction have been identified and modelled. The work is based on theoretical calculation as well as on experimental measurements carried out on a purpose-built test rig. The model takes into account the materials used and the gear mesh characteristics and enables the prediction of the steering gear friction performance before the very first prototypes are built.

Keywords: Friction | Rack and pinion | Steering | Steering feel | Vehicle dynamics

[26] Uberti S., Gadola M., Chindamo D., Romano M., Galli F., Design of a double wishbone front suspension for an orchard-vineyard tractor: Kinematic analysis, Journal of Terramechanics, 57, 23-39, (2015). Abstract
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Abstract: This paper deals with the design and implementation of a double wishbone front suspension for a vineyard-orchard tractor, developed in conjunction with a major tractor brand. To date, independent front suspensions are only found on commercial tractors over 150 kW. A front suspended axle is recognized as a popular option in improving tractor ride performance on larger vehicles. Despite their narrow track, vineyard-orchard tractors are required to have good lateral stability and stability on slopes (i.e. at least 28° rollover angle) and an extremely tight turning diameter for a 4WD vehicle (less than 7 m). The discussion is concered with retrofitting an existing vehicle with a double wishbone front suspension. This paper focuses on the layout and kinematic analysis phases of the design process. These were conducted in collaboration with the vehicle manufacturer to demonstrate suspension feasibility in terms of available space and correct kinematic layout. The final kinematic turning diameter obtained is about 6.4 m, with a ±65 mm suspension travel available. The roll centre height value is not very sensitive to steering (about -95 mm excursion in the Z axis from no-steer position to full steer).

Keywords: Double wishbone suspension | Front axle independent suspension | Narrow-track tractor | Suspension design

[27] Uberti S., Baronio G., Cambiaghi D., Study & design of a special test bench for hydrostatic spindle housings, 11th International Design Conference, DESIGN 2010, 1729-1740, (2010). Abstract
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Abstract: This paper deals with the study, design, manufacturing & testing of a particular scientific instrument, functional to investigate hydrostatic bushing behaviour under various experimental conditions. Job was conducted in concurrence with one of the leading companies in rotary transfer machines business. Machining is performed by hydrostatic unit, in which spindle assembly is contained in a sliding tube supported by a set of hydrostatic bushings. In this paper we will detail the design of a "research & test" bench whose aim is to help in developing new hydrostatic bushing systems.

Keywords: Design | Hydrostatic | Spindle | Test bench

[28] Uberti S., Gadola M., Design of a new high-end street bike, 11th International Design Conference, DESIGN 2010, 1741-1752, (2010). Abstract
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Abstract: This paper deals with an "atypical" bike design. It can be considered atypical due to the materials used and the peculiar engine - chassis combination. The project was born as a consequence of the manufacturing company desire to access a niche motorcycle market. The project is about a new bike with an adequate family feeling with the factory style, totally customizable; it will be a large capacity, naked sporty two-seater, with innovative design and a very good handling. In the paper the entire design process leading to the presentation will be briefly explained.

Keywords: Chassis | Design | Handling | Motorcycle

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