Design methods for mobility

The following scientific paper aims to analyze in detail the methodology for reverse engineering of a racing motorcycle connecting rod. The objective is to start with a product available on the market as a spare part, reconstruct its CAD model with a high standard of accuracy, then proceed with lightening modifications to arrive at a new, improved design. The innovative aspect of the procedure lies in the fact that in order to ensure accuracy on the order of a tenth of a millimeter during reconstruction, it was decided to use a FARO articulated arm laser to scan the component's outer surface. By taking advantage of appropriate redesign CAD software (Geomagic Design X), a reconstruction can proceed within the high standard of accuracy imposed. In conclusion, the modifications made through material removal allow an improvement in product efficiency, ensuring high performance.

Keywords: CAD modelling , conrod , high-precision modeling , redesign , reverse engineering

The performance of modern, new generation-armored vehicles would greatly benefit from overall engineering, optimization, and integration techniques of advanced diesel engines-electrified transmissions. Modern axial flux electric motors and controllers are perfectly able to replace the classical automatic gearbox and complex steering system of traditional Main Battle Tanks. This study shows a possible design of a serial hybrid electric power pack for very heavy tanks with a weight well over 50 tons. The result is a hybrid power system that improves the overall performance of armored vehicles off-road and on-road, improving the acceleration and the smoothness of the ride. In addition, fuel consumption will be reduced because the internal combustion engine operates at fixed rpm. The electric motors will outperform the traditional engines due to their very high torque output even at “zero speed”. The weight of a hybrid system has also been calculated. In fact, in many cases, it is possible to use all off-the-shelf components. The on-board diagnosis of the subsystems in the hybrid powertrain makes it possible to achieve a Time Between Overhaul (TBO) of 4500 h with a failure probability inferior to one in 10,000.

Keywords: EV , heavy vehicles , hybrid powertrains , MBT

Living labs (LLs) are identified as innovation ecosystems to test and facilitate the diffusion of complex technological innovation, rising attention especially on cutting-edge automotive technologies. Autonomous and connected vehicles are indeed expected to deeply affect the automotive industry and the society in the coming years, by involving important technological, political, social, and legal issues. In such a complex framework, where different fields and stakeholders are deeply intertwined, new modes of interaction between multiple actors are necessary to support such technological innovation. By focusing on the case of the Modena Automotive Smart Area, an urban LL located within the Italian Motor Valley, we analyze the evolution of roles and relationships among the involved government, academia and industry actors. More specifically, by adopting the lens of Triple Helix model in practice, the purpose of the paper is to analyze how the actors contribute to and relate within the knowledge, consensus and innovation spaces, in a time span from before the formal inception of the LL to three years after. Results highlight how actors' collaboration and participation unfold in the creation of the LL when complex innovative technologies are tested in real urban environment, hence contributing to burgeoning literature on LL and the current academic debate on triple helix model. Policy and practical implications are also derived

Keywords: Autonomous driving , Living lab , Technological innovation , Triple helix model

This study introduces the simulation of a tri-rotor contra-rotating propeller for thrust force and hover lift efficiency during vertical take-off. Vertical take-off or landing is a method used by many aircraft and makes the vehicle more convenient and easier to use. The second rotor revolved in the opposite direction of the first and third rotors. The proposed multi-rotor system has NACA 0012 untwisted and symmetric airfoil and includes three rotors with two blades for each. The airflow analysis was optimized with computational fluid dynamics simulation by using different pitch combinations to achieve the highest hover lift efficiency with sufficient overall thrust value. The critical angle of attack for the chosen airfoil gave the boundary conditions for the pitch of rotors. The results showed us that the most efficient combinations for three rotors work better with an increase of pitch angle from top to bottom so that there is a difference of at least two degrees between propellers. Experiments with angles of attack within the boundary conditions showed that the blade combinations starting from three degrees and increasing values gave positive and adequate results in many cases. In addition, the results showed that a regular increase in the angle of attack does not relate to a regular increment in thrust force.

Keywords: Airfoil , Coaxial propeller , Disc loading , Hover lift efficiency , Hovering , Multi-rotor propeller , Optimization , Thrust force , Tiltrotor

In aeronautics, additive manufacturing (AM) leads to specific benefits, mainly connected to topological optimization for weight reduction, the decrease in “buy-to-fly” ratio, and the operations of maintenance, repair, and overhaul. Al alloys processed by AM technologies are extensively investigated and play an increasing role in the production of aircraft structural parts. Based on the recent literature and research activity of the authors, this work examines advantages and drawbacks involved in the printing of Al alloys. Defects, microstructure, mechanical properties, development of new alloys, and postprocess treatments are described and critically discussed by focusing the attention on the effects of the specific alloy composition, AM process, and process parameters.

Keywords: additive manufacturing , aeronautics , Al alloys , defects , mechanical properties , microstructure

The alternation of dry and wet contact causes a complex interaction of various damage mechanisms in railway wheels. To study the damage evolution in such condition, rolling-sliding contact tests in alternated dry-wet contact were carried out by a bi-disc machine on specimens extracted from railway wheels. The effect of different durations of the dry and wet sessions was investigated. Two kinds of tests were done: in one case coupling two cylindrical specimens, in the other one coupling a cylindrical specimen with a crowned one. The surface appearance during the tests was acquired by a vision system; the acquired images were elaborated to extract quantitative damage indexes. At the end of the tests, the specimens were cut and analysed, to evaluate the subsurface damage and the strain hardening. In cylindrical-cylindrical coupling, the damage increased in alternated dry-wet sessions as far as the cycle number increased, whereas it was stabilized in long dry sessions. The prevailing phenomenon, occurring during the wet sessions, was fatigue, promoted by the pressurization of the water entrapped in the cracks previously formed in dry contact. In crowned-cylindrical couplings, the damage tended to decrease as far as the cycles increased, in all the test conditions. This was correlated to the widening of the contact patch caused by wear, which led to an overall stress relaxation, this way mitigating the damage. The results highlighted the double role of wear, which alters the optimum wheel profile, but at the meantime relaxes the overall stress state and mitigates rolling contact fatigue.

Keywords: Damage monitoring , Dry-wet contact , Railway wheel steel , Rolling contact tests , Vision system

In automotive and industrial application domains, the "health monitoring"or predictive reliability of electronic devices plays a key-role in ensuring reliability of the electrical components. Health monitoring regards a collection of methods aimed at monitoring the operational features and performance of an electronic components in order to schedule preventive/predictive maintenance. Similarly, predictive reliability makes it possible to test electronic devices in an intelligent manner, i.e. by identifying predictive patterns of degradation or anomalous behavior in order to effectively characterize the monitored systems. Specifically, the authors of the present work will show the excellent results obtained by applying artificial intelligence techniques to the monitoring by optical microscopy of the power modules in Silicon Carbide technology usually placed in the traction inverter of electric vehicles. The Silicon-Carbide Power Module is a key component embedded in the traction inverter-system of the modern electric cars, and its functional degradation or unusual behavior may have a significant negative impact on the car's safety. As with any electronic components, the power module is subjected to electro-mechanical stresses which impact its functionality over time, highlighting progressive states of physical degradation. One technique for detecting defects in Silicon-Carbide Power Modules is optical microscopy. Through ad-hoc deep learning system based on the use of an enhanced YOLOv5 architecture, the captured optical microscopic image of the analyzed Silicon-Carbide Power Module will be automatically processed providing in output a bounding-box segmentation of the most impactful and significant defect patterns for the functioning of the monitored power device. Several tests have been performed on different power modules of the ACEPACKTM DRIVE series delivered by STMicroelectronics. The collected performance (identification and classification accuracy close to 93%) confirmed the effectiveness of the proposed solution.

Keywords: Deep Learning , Optical Microscopy , Power Modules

In this work, a method to thermally characterize a power semiconductor module based on silicon carbide for traction inverters is presented. In general, this is important in order to determine the real thermal behavior of the system and, consequently, to forecast the application reliability performances. Thermal impedance is measured by a dedicated bench, capable to heat power module by applying a constant current, yet ensuring a controlled liquid cooling environment. The obtained experimental curve is then translated into a system made by several RC ports, obtained employing convolution's algorithms. Solving the related differential equations, temperature profile can be obtained as function of time. Considering the actual application power loss, the related temperature profile can be calculated and collected in a discrete number of different load cases characterized by a duration and a thermal swing.

Keywords: Numerical simulation , Power Module , Reliability , Silicon Carbide , Thermal characterization

Automotive domain is making rapid growth in next generation cars development embedding higher levels of autonomy and intelligent assistance. Although the general advanced driver assistance system (ADAS) architectures are widely debated in the global automotive market, limited interaction between driver and these intelligent solutions sometimes make these solutions inefficient. For these reasons, the authors started an investigation about driver's feedback with respect to the intelligent assistance inputs provided by the ADAS technologies. In this context, the goal of this proposal is to show the implemented intelligent system which learns from the analysis of the car driver's eyes saccadic movements, the correlated level of attention towards the salient driving scene. With this approach, the authors were able to collect a kind of visual-feedback signal which learns the driver eye's fixing dynamic associated to the analyzed driving scene. Through ad-hoc enhanced motion magnification technique, the authors were able to amplify the mentioned saccadic dynamics to allow a downstream deep classifier to associate this physiological behavior with the corresponding level of the driver attention. The collected performances (near to 97)

Keywords: ADAS , Deep Learning , Driver eye saccadic movements , Motion Magnification

In automotive and industrial domains, the “health monitoring” or “condition monitoring” of electronic devices is gradually playing a key role in manufacturing processes and innovation roadmaps. The concept of health monitoring is often related to the so-called “residual lifetime” of the monitored system. In this work, the authors have designed a deep learning system for the health monitoring of power devices in Silicon Carbide (SiC) technology used in the Traction Inverter Systems of the latest generation electric cars. A Temporal Fusion Transformer embedding such layers of Temporal Convolutional Network with a Multi-Head Attention block for the robust lifetime assessment of SiC power devices, is proposed...

Keywords: Device Health Monitoring , Intelligent vehicles , Inverters , Monitoring , Multichip modules , Performance evaluation , SiC Power Module , Silicon carbide , Temperature measurement , Temporal Fusion Transformer

With the rapid advancement of autonomous vehicles, a transformative transportation paradigm is emerging in the automotive industry, necessitating a re-evaluation of how users engage with and utilize these evolving settings. This research paper introduces an innovative interaction system tailored for shared autonomous vehicles, focusing on its development and comprehensive evaluation. The proposed system uses the car's windshield as an interactive display surface, enabling infotainment and real-time information about the surrounding environment. The integration of two gesture-based interfaces forms a central component of the system. Through a study involving twenty subjects, we analyzed and compared the user experience facilitated by these interfaces. The study outcomes demonstrated that the subjects exhibited similar behaviors and responses across both interfaces, thus validating the potential of these interaction systems for future autonomous vehicles. These findings collectively emphasize the transformative nature of the proposed system and its ability to enhance user engagement and interaction within the context of autonomous transportation.

Keywords: autonomous vehicle , gesture , haptic , head up display , human computer interaction , human machine interface , user experience

Nowadays, the topic of reducing vehicles' energy consumption is very important. In particular, for electric vehicles, the reduction of energy consumption is necessary to remedy the most critical problems associated with this type of vehicle: the problem of the limited range of the electric traction, also associated with the long recharging times of the battery packs. To reduce use-phase impacts and energy consumptions of vehicles, it is useful to reduce the vehicle mass (lightweighting). The aim of this work is to analyze the parameters of a vehicle which influence the results of lightweighting, in order to provide guidelines for the creation of a vehicle model suitable for studying the effects of lightweighting. This study was carried out through two borderline case models, a compact car and an N1 vehicle, and simulating these through a consolidated vehicle simulation tool useful for consumption estimations. This study shows that the parameters that most influence the outcome of lightweighting are the rolling resistance, the battery pack characteristics, the aerodynamic coefficients, and the transmission efficiency, while the inertia contributions can be considered negligible. An analysis was also carried out with the variation of the driving cycle considered.

Keywords: automotive , consumption analysis , energy consumption , Energy Reduction Value (ERV) , Fuel Reduction Value (FRV) , vehicle lightweighting

To promote the development of new technologies that allow an intensive use of renewable green energies and to overcome the problem of the lack of range of full electric vehicles, an interesting energy source is biomethane. The Fuel Cells (FCs) systems benefit from high efficiency and zero emissions, and they are generally powered by hydrogen. One of the main problems related to hydrogen FCs is the current weak network of infrastructure's need to supply the hydrogen itself. An alternative may be the development of FC vehicles powered by methane, or biomethane, to exploit a renewable energy source. The type of Fuel Cells that lends itself to a methane (or biomethane) power supply is the Solid Oxide Fuel Cell (SOFC). Considering the limitations of the SOFCs, a vehicle model powered by Fuel Cells fueled by methane (or biomethane) is created. This work concerns the creation of a vehicle model, and the sizing of the SOFC system (generator delivering a constant 3 kW) and battery pack (30 Ah), for a door-to-door waste collection vehicle, whose mission is known. The latter is a fundamental requirement due to the limitations found for Solid Oxide Fuel Cells: slow transient and long ignition times.

Keywords: alternative propulsion , energy consumption , Fuel Cells powered by methane , mathematical modeling , Solid Oxide Fuel Cell (SOFC) , vehicle model

In the contemporary automobile scene, environmental effect abatement is being increasingly sought; this demands a full rethinking of the entire system and entails more than just the reduction in exhaust pollutant emissions. Currently, the most popular approach is the electrification of automobiles, which significantly reduces pollution in major urban areas while simultaneously posing a new set of problems. The two types of zero-emission vehicles that are now being developed the most are hydrogen fuel cells and battery electric cars, but another option is the Hydrogen Internal Combustion Engine (HYICE) engine, which is highly advantageous in terms of pollutants, aside from Nitrogen Oxides (NOx), which can be considerably decreased. The purpose of this study is to develop a novel vehicle design that transports this type of technology into a sporting context while striving for considerable environmental benefits and integrating them into a society where the love of automobiles still has a strong following. The cutting-edge Industrial Design Structure (IDeS) methodology is used in this work, and a sample structure was created to demonstrate how the problems and technical limitations represented can be solved. The steps of the methodology are followed to shape the final product, with careful consideration given to the design of the styling component through the use of the Stylistic Design Engineering (SDE) method. With the ultimate goal of achieving sustainable driving pleasure, the study looks into whether recyclable materials can be used for the body and whether extremely light materials can be used for the chassis.

Keywords: car design , future mobility , HYICE engine , IDeS methodology , recyclable materials

Several emotion-adaptive systems frameworks have been proposed to enable listeners' emotional regulation through music reproduction. However, the majority of these frameworks has been implemented only under in-Lab or in-car conditions, in the second case focusing on improving driving performance. Therefore, to the authors' best knowledge, no research has been conducted for mobility settings, such as trains, planes, yacht, etc. Focusing on this aspect, the proposed approach reports the results obtained from the study of relationship between listener's induced emotion and music reproduction exploiting an advanced audio system and an innovative technology for face expressions' recognition. Starting from an experiment in a university lab scenario, with 15 listeners, and a yacht cabin scenario, with 11 listeners, participants' emotional variability has been deeply investigated reproducing 4 audio enhanced music tracks, to evaluate the listeners' emotional “sensitivity” to music stimuli. The experimental results indicated that, during the reproduction in the university lab, listeners' “happiness” and “anger” states were highly affected by the music stimuli and highlighted a possible relationship between music and listeners' compound emotions. Furthermore, listeners' emotional engagement was proven to be more affected by music stimuli in the yacht cabin, rather than the university lab.

Keywords: Affective Computing , Audio Enhancement , Deep Learning , Facial Emotion Recognition

In this paper we present the preliminary evaluation of an active soft bellow exoskeleton for assistance during overhead tasks. The evaluation was performed using objective (i.e., joint angles and muscle activations) and subjective (i.e., Borg Cr R-10 and System Usability Scale - SUS scales) measurements. The subject, involved in the experimental campaign, performed in laboratory conditions a drilling overhead task typical of the automotive industry, once using the exoskeleton and once without the exoskeleton. The preliminary results underlined the positive effect of the exoskeleton in terms of physical effort and usability.

Keywords: biomechanics , overhead tasks , soft exoskeletons , usability

In wide-ranging areas, including hydraulics, biomedical, automotive, and aerospace, there is often a need to move a fluid with a constant flow rate. This is difficult to achieve with any type of pump and usually other elements are inserted to regularize the output. This study focused on the peristaltic pump because there are few studies on it and it has some interesting features, such as extreme simplicity, a small number of components, and the extreme compactness of the whole system. The first part of this study is focused on analyzing the classical geometry of the peristaltic pump to understand the origin of the discontinuity in the flow rate; the second part proposes a new geometry that mitigates the flow irregularity by more than 200%. In this way, it is possible to use it in all the sectors where a constant flow rate is required but where insulation between the fluid and the machine is required. Together with the flow study, an analysis of how the main geometric parameters affect the operation of the pump is provided, complete with explanatory graphs and tables. A prototype made through additive manufacturing technologies is also proposed.

Keywords: 3D printing , calculation , constant flow rate , fluid transfer , peristaltic pump

The research on technologies and methodologies for (accurate, real-time, spontaneous, three-dimensional…) facial expression recognition is ongoing and has been fostered in the past decades by advances in classification algorithms like deep learning, which makes them part of the Artificial Intelligence literature. Still, despite its upcoming application to contexts such as human–computer interaction, product and service design, and marketing, only a few literature studies have investigated the willingness of end users to share their facial data with the purpose of detecting emotions. This study investigates the level of awareness and interest of 373 potential consumers towards this technology in the car insurance sector, particularly in the contract drafting phase, with a focus on differentiating the respondents between generation Y and Z. Results show that younger people, individuals with higher levels of education, and social network users feel more confident about this innovative technology and are more likely to share their expressive facial data.

Keywords: Facial expression recognition , Insurance market , Survey , Technology acceptance , Technology propensity , Young consumers

Introduction: Wire rope isolators are often used as means of vibration isolation for the transportation of fragile machine equipment. When deployed as suspension systems in a transportation scenario, a simple spring–damper model is often used to predict the dynamic loads that act on the structure being transported. However, this simple model has proved to be too simplistic to be used in the development of an accurate numerical model that can predict the vibration levels experienced by the inner components of fragile equipment during its transportation. This paper describes the experimental tests conducted on a wire rope isolator used for the transportation of the prototype SSR1 cryomodule. Materials and methods: A hysteretic Bouc–Wen model has been used to analytically describe the force–deformation relationship of the wire rope isolators. The developed model of the isolator has been implemented in a larger model to simulate the actual transportation of the prototype SSR1 cryomodule, a section of the new PIP-II linear accelerator under construction at Fermilab. A series of multibody dynamic simulations with rigid and flexible components was used to numerically determine the acceleration of some critical components. Results and conclusions: An actual experimental transportation was simulated using two numerical models: the developed Bouc–Wen model and a conventional spring–damper model. It is shown how the Bouc–Wen formulation of the isolator characteristics drastically improves the correspondence between experimental and simulated results if compared to a spring–damper model, especially in the range of 0–30 Hz which is the most critical for transportation problems.

Keywords: Cryomodules , Experimental test data , Finite-element modeling , Multibody simulations , Reduced order methods , Vibration measurements

In this paper, a human-centered design methodology is proposed to support the interiors design of a Maritime Patrol Aircraft (MPA). The combined use of Immersive Virtual Reality (VR) tools and Digital Human Models (DHMs) are exploited to include both objective and subjective measurements in the ergonomic evaluation process. The main issue consisted in defining the optimal ergonomic design configuration for Operator Console Area and Observer Window Area of MPA's digital mock-up, provided by Leonardo S.p.A. The methodology is based on a five-step iteration process: once having identified the requirements, required input data and the design variables, the ideated configuration is evaluated using DHMs in order to retrieve objective measurements (i.e., interferences, visibility, reachability); finally, a subjective assessment within immersive VR environment is conducted. A real-time RULA analysis is carried out on DHMs, calibrated on selected users representing specific percentages of target population, by means of a full-body tracking system. The subjective assessment in immersive VR allows to take into account also other human factors (i.e. human ability, dexterity and cognitive aspects) that have not been previously considered and may significatively influence the validation of the final design configuration of MPA interiors.

Keywords: Digital Human Modeling , Digital Mock-up , Ergonomic Validation , Maritime Aircraft , Virtual Reality