Design methods for mobility

This paper presents a regenerative braking logic that aims to maximize the recovery of energy during braking without compromising the stability of the vehicle. This model of regenerative braking ensures that the regenerative torque of the electric motor (for front- and rear-wheel drive vehicles) or electric motors (for all-wheel drive vehicles equipped with one motor for each axle) is exploited to the maximum, avoiding the locking of the driving wheels and, subsequently, if necessary, integrating the braking with the traditional braking system. The priority of the logic is that of maximizing energy recovery under braking, followed by the pursuit of optimal braking distribution. This last aspect in particular occurs when there is an integration of braking and, for vehicles with all-wheel drive, also when choosing the distribution of regenerative torque between the two electric motors. The logic was tested via simulation on a front-, rear-, and all-wheel drive compact car, and from the simulations, it emerged that, on the WLTC driving cycle, the logic saved between 29.5 and 30.3% in consumption compared to the same vehicle without regenerative recovery, and 22.6–23.5% compared to a logic commonly adopted on the market. On cycle US06, it saves 23.9–24.4% and 19.0–19.5%, respectively.

Keywords: electric vehicle , energy optimization , energy recovery , EV , regenerative braking logic , vehicle stability

The so-called porpoising is a well-known problem similar to bouncing that is affecting the dynamic behavior of basically all the field of 2022 Formula 1 racing cars. It is due to the extreme sensitivity of aerodynamic loads to ride height variations along a lap. Mid-way through the season race engineers are still struggling to cope with this phenomenon and its consequences, with regard to either physiological stress experienced by the drivers or to overall vehicle performance and stability. The paper introduces two kinds of models based on real-world chassis and aerodynamic data, where the above-mentioned downforce sensitivity has been arbitrarily recreated through the application of a decay function to aero maps. The first one is a quasi-static model, usually adopted as a trackside tool for controlling ride heights and aero balance, while the second, a fully dynamic model, recreates the interaction between oscillating aerodynamic loads and suspension dynamics resulting in a visible porpoising phenomenon. Basic setup changes have been tested, including significant static ride height variations. The paper should be seen as a proposal of guidelines in the search of a trade-off between aerodynamic stability and overall performance, without pretention of quantitative accuracy due to the highly confidential topic, which makes numerical validation impossible.

Keywords: aerodynamic efficiency , aerodynamic stability , high-downforce race cars , vehicle dynamics simulations

This paper presents a modularity analysis for the design of complex products, based on domain theory, applied to the case study of the design of an electro-solar vessel to be implemented in South American rivers. The proposed approach allows obtaining graphical information from the functional analysis tools, about the interaction between functional modules or organs of the system in terms of material, energy, or information flows; useful to analyze the functional architecture, the types of modularity and the interactions in the system. This information is complemented with the approach to the physical architecture of the system identifying interferences and restrictions. This information is intended to be useful in the development of methods or methodologies for the definition of the assembly sequence.

Understanding user experience (UX) is essential to design engaging and attractive products, so nowadays has emerged an increasingly interest in user-centred design approach; in this perspective, digital technologies such as Virtual Reality (VR) and Mixed Reality (MR) could help designers and engineers to create a digital prototype through which the user feedback can be considered during the product design stage. This research aims at creating an interactive Digital Twin (DT) using MR to enable a tractor driving simulation and involve real users to carry out an early UX evaluation, with the scope to validate the design of the control dashboard through a transdisciplinary approach. MR combines virtual simulation with real physical hardware devices which the user can interact with and have control through both visual and tactile feedback. The result is a MR simulator that combines virtual contents and physical controls, capable of reproducing a plowing activity close to reality. The principles of UX design was applied to this research for a continuous and dynamic UX evaluation during the project development.

Keywords: Digital Engineering , Digital Twin , Human-centered Design , Mixed Reality , User experience design

The High Energy cosmic-Radiation (HERD) detector is one of the prominent space-borne instruments to be installed on-board the Chinese Space Station (CSS), around 2027. Primary scientific goals regarding this initiative include: precise measurements of cosmic ray (CR) energy spectra and mass composition, at energies up to the PeV range; contributions to high energy gamma-ray astronomy and transient studies; as well as indirect searches for Dark Matter (DM) particles via their possible annihilation/decay to detectable products. HERD is configured to accept incident particles from both its top and four lateral sides. Owing to its pioneering design, an order of magnitude increase in acceptance is foreseen, with respect to previous and ongoing experiments. The Plastic Scintillator Detector (PSD) constitutes an important sub-detector of HERD, particularly aimed towards anti-coincidence (discriminating incident photons from charged particles), while providing precise charge measurement of incoming cosmic-ray nuclei in a range of Z = 1-26. Main requirements concerning its design, include: high detection efficiency, broad dynamic range and good energy resolution. In order to select the optimal layout, two geometries are currently under investigation: one based on long scintillator bars and the other on square tiles, with both layouts being readout by Silicon Photomultipliers (SiPMs). Ongoing activities and future plans regarding the HERD PSD will be presented in this work.

Keywords: Charged particles , Cosmology , Gamma rays , Scintillation counters , Space stations

Crystal Eye is a new concept of all sky monitor for the observation of 10keV-30MeV cosmic photons exploiting a new detection technique, which foresees enhanced localization capability with respect to current instruments. This is now possible thanks to the use of new materials and sensors. The proposed detection module is designed to be easily installed either on free flyer satellites or onboard space stations. Science goals include Gamma Ray Bursts, electromagnetic counterpart of Gravitational Wave emissions, Active Galactic Nuclei and line emission from supernova explosions observations. A Crystal Eye pathfinder, made by 4 pixels, has been set up to fly aboard of the Space RIDER, an uncrewed reusable orbital spaceplane aiming to provide the European Space Agency (ESA) with affordable and routine access to space. The mission will follow a LEO orbit (400 km, 5.3° of inclination) for two months then it will come back at the base. We here present the Crystal Eye detection method and characteristics and the first characterization of the pathfinder.

Keywords: Cosmology , Eye protection , Gamma rays , Gravity waves

Researchers involved in the development of dexterous robotic hands agree that a mechatronics approach to hand design is the only way to generate new levels of functional capabilities. As reported by several authors, the problems relative to the single component or subsystem design must be solved within a general frame of compatibility and integrability. In this paper the virtual and physical prototyping of a three-fingered gripper designed to be mounted on an autonomous underwater vehicle (AUV) for underwater manipulation as well as sampling specimens is reported. In particular, an overall description of the gripper design is discussed, with special attention to the required actuation and tendon transmission system, its integration within the mechanical structure and the required control architecture. Different solutions for the joint configuration and the structure of the tendon network adopted for the transmission system are presented. The integrated design of the finger is reported and the motivations leading to this particular implementation are thoroughly addressed, taking into account both the mechanical constraints and the control requirements. The overall finger design is modular, so that other design solutions comprising multiple fingers (e.g. for in-hand manipulation purposes or realization of cage gripper) are easily achievable by adding further modules without increase the overall dimensions of the device. Virtual prototype results are finally provided and discussed to prove the gripper behaviour and capabilities.

Keywords: Autonomous underwater vehicles , Tendons

The driving behaviour of Connected and Automated Vehicles (CAVs) may influence the final acceptance of this technology. Developing a driving style suitable for most people implies the evaluation of alternatives that must be validated. Intelligent Virtual Drivers (IVDs), whose behaviour is controlled by a program, can test different driving styles along a specific route. However, multiple combinations of IVD settings may lead to similar outcomes due to their high variability. The paper proposes a method to identify the IVD settings that can be used as a reference for a given route. The method is based on the cluster analysis of vehicular data produced by a group of IVDs with different settings driving along a virtual road scenario. Vehicular data are clustered to find IVDs representing a driving style to classify human drivers who previously drove on the same route with a driving simulator. The classification is based on the distances between the different vehicular signals calculated for the IVD and recorded for human drivers. The paper includes a case study showing the practical use of the method applied on an actual road circuit. The case study demonstrated that the proposed method allowed identifying three IVDs, among 29 simulated, which have been subsequently used as a reference to cluster 26 human driving styles. These representative IVDs, which ideally replicate the driving style of human drivers, can be used to support the development of CAVs control logic that better fits human expectations. A closing discussion about the flexibility of the method in terms of the different natures of data collection, allowed for depicting future applications and perspectives.

Keywords: automotive engineering , autonomous driving , driving behaviour , driving simulator , intelligent agents , pattern clustering

This work presents an aerodynamic and structural optimization for a Droop Nose Leading Edge Morphing airfoil as a high lift device for the UAS-S45. The results were obtained using three optimization algorithms: coupled Particle Swarm Optimization-Pattern Search, Genetic Algorithm, and Black Widow Optimization algorithm. The lift-to-drag ratio was used as the fitness function, and the impact of the choice of optimization algorithm selection on the fitness function was evaluated. The optimization was carried out at various Mach numbers of 0.08, 0.1, and 0.15, respectively, and at the cruise and take-off flight conditions. All these optimization algorithms obtained effectively comparable lift-to-drag ratio results with differences of less than 0.03% and similar airfoil geometries and pressure distributions. In addition, an unsteady analysis of a Variable Morphing Leading Edge airfoil with a dynamic meshing scheme was carried out to study its flow behaviour at different angles of attack and the feasibility of leading-edge downward deflection as a stall control mechanism. The numerical results showed that the variable morphing leading edge reduces the flow separation areas over an airfoil and increases the stall angle of attack. Furthermore, a preliminary investigation was conducted into the design and sensitivity analysis of a morphing leading-edge structure of the UAS-S45 wing integrated with an internal actuation mechanism. The correlation and determination matrices were computed for the composite wing geometry for sensitivity analysis to obtain the parameters with the highest correlation coefficients. The parameters include the composite material qualities, thickness, ply angles, and the ply stacking sequence. These findings can be utilized to design the flexible skin optimization framework, obtain the target droop nose deflections for the morphing leading edge, and design an improved model

Keywords: algorithms , composite , correlation matrix , morphing airfoil , optimization , unsteady aerodynamics

This study is on the conception of the DS700 HYBRID project by the application of the Industrial Design Structure method (IDeS), which applies different tools sourced from engineering and style departments, including QFD and SDE, used to create the concept of a hybrid motorbike that could reach the market in the near future. SDE is an engineering approach for the design and development of industrial design projects, and it finds important applications in the automotive sector. In addition, analysis tools such as QFD, comprising benchmarking and top-flop analysis are carried out to maximize the creative process. The key characteristics of the bike and the degree of innovation are identified and outlined, the market segment is identified, and the stylistic trends that are most suitable for a naked motorbike of the future are analyzed. In the second part the styling of each superstructure and of all the components of the vehicle is carried out. Afterwards the aesthetics and engineering perspectives are accounted for to complete the project. This is achieved with modelling and computing tools such as 3D CAD, visual renderings, and FEM simulations, and virtual prototyping thanks to augmented reality (AR), and finally physical prototyping with the use of additive manufacturing (AM). The result is a product conception able to compete in the present challenging market, with a design that is technically feasible and also reaches new lightness targets for efficiency.

Keywords: additive manufacturing , augmented reality , benchmarking , design engineering , Industrial Design Structure (IDeS) , motorcycle design , Quality Function Deployment (QFD) , Stylistic Design Engineering (SDE) , topology optimization

This case study aims to develop a new innovative SUV (Sport Utility Vehicle) model exploiting IDeS (Industrial Design Structure), which is an engineering approach conceived to optimize car design projects in the automotive industry like never before. A compact SUV was chosen because it is a type of vehicle that is highly requested by customers, and it is extremely successful in the market due to its versatility. In fact, compact SUVs are mixed vehicles that combine the pragmatism of a car with the typical robustness of an off-road vehicle making them suitable both for urban and off-road scenarios. The following pages will illustrate the steps followed for the realization of the final product using the SDE (Stylistic Design Engineering) method and other various design technologies, such as Quality Function Deployment (QFD), Benchmarking (BM) and Top Flop Analysis (TPA). In the final part of this project, the virtual prototyping of the product is carried out using Additive Manufacturing (AM) with an FDM 3D printer. The combination of these methods forms, to all intents and purposes, the IDeS, a newly developed innovative and cutting-edge discipline capable of schematically guiding the new product development process in companies with unprecedented efficiency.

Keywords: CAD modelling , car design , IDeS , innovation , QFD , SDE

The High Energy cosmic-Radiation Detection (HERD) facility has been proposed as a space astronomy payload onboard the future China's Space Station. HERD is planned for operation starting around 2027 for about 10 years In addition to the unprecedented sensitivity for dark matter searches and cosmic-ray measurements up to the knee energy, it should perform gamma-ray monitoring and full sky survey from few hundred MeV up to tens of TeV. We present the first study of the HERD gamma-ray performance obtained with full simulations of the whole detector geometry. HERD will be a cubic detector composed with 5 active faces. We present a study conducted inside the HERD analysis software package, which includes a detailed description of the detector materials. In this work we present the HERD effective area, the point spread function and the resulting gamma-ray sensitivity.

Keywords: Cosmology , Gamma rays , Optical transfer function , Space stations

The High Energy cosmic-Radiation Detection (HERD) facility is a space payload proposed to be installed onboard the China's Space Station (CSS). The aims of HERD are the indirect detection of dark matter, the direct detection of cosmic rays towards the “knee” of the spectrum (∼ 1 PeV) and the monitoring of the full gamma-ray sky from 100 MeV. The HERD core is a calorimeter capable of accepting particles incident on its top and four lateral sides, each equipped with a sector of the scintillating fiber tracker: FIT. The FIT sectors host 7 tracking planes made of modules. The module, composed of a fiber mat and three arrays of silicon photomultipliers (SiPMs), is the elementary brick of FIT. Several FIT modules have been built and tested with particle beams at CERN. A FIT demonstrator, made of two partially instrumented tracking planes, has been assembled and sent through vibration tests. The results of the performed tests as well as the current design of FIT are presented in this contribution.

Keywords: Cosmology , Gamma rays , Scintillation , Space stations

The High Energy cosmic-Radiation Detection (HERD) facility is a next generation spaceborne detector to be installed onboard the Chinese Space Station for about 10 years. HERD will address major problems in fundamental physics and astrophysics, providing precise measurements of charged-cosmic rays up to PeV energies, performing indirect searches for dark matter in the electron spectrum up to few tens of TeV and monitoring the gamma-ray skymap for surveys and transient searches. HERD is composed of a 3D imaging calorimeter (CALO) surrounded by a scintillating fiber tracker (FIT), a plastic scintillator detector (PSD) and a silicon charge detector (SCD). In addition, a transition radiation detector (TRD) is placed on a lateral side to provide accurate energy calibration. Based on this innovative design, the effective geometric factor of HERD will be one order of magnitud larger than that of current space-based detectors. The HERD trigger strategy is designed to accomplish the scientific goals of the mission, and is based on trigger definitions that rely on the energy deposited in CALO and the PSD. The trigger performances are evaluated using a detailed Monte Carlo simulation that includes the latest HERD geometry. In addition, alternative trigger definitions based on the event topology can be established thanks to the photodiode readout of CALO crystals. The feasibility of these topological triggers is also investigated and presented.

Keywords: Cosmology , Gamma rays , Intelligent systems , Monte Carlo methods , Space stations , Tellurium compounds , Topology

The High Energy cosmic-Radiation Detection (HERD) is a future space experiment which will be installed on the China's Space Station around 2027. The main goal of the experiment is the measurement of cosmic rays up to energies which are not explored by the instruments currently operating in space, in particular protons with energies up to PeV, nuclei up to hundreds of TeV per nucleon and electrons up to tens of TeV. HERD will consist of silicon charge detectors, anti-coincidence scintillators, scintillating fiber trackers, a transition radiation detector and a calorimeter. The latter is a homogeneous, deep, 3D segmented calorimeter made of about 7500 LYSO cubic crystals: thanks to this innovative design, it will achieve large acceptance, good energy resolution and excellent electron/proton discrimination. In order to increase both energy calibration capabilities and redundancy of the instrument, the LYSO scintillation light will be read-out by two independent systems: the first is made of wave-length shifting fibers coupled with imaged intensified CMOS cameras, and the second one consists of photodiodes with different active areas connected to a custom front-end electronics. Both read-out systems are designed to have a large dynamic range, up to 107, and a low power consumption. The design of the calorimeter is validated by several Monte Carlo simulations and beam test results obtained with detector prototypes. In this paper we describe the anticipated performances of the calorimeter and the current status of the double read-out system, and we discuss the recent developments of both the HERD prototype and the flight model design.

Keywords: Cosmic rays , Cosmology , Intelligent systems , Monte Carlo methods , Scintillation counters , Silicon detectors , Space stations

Metal Additive Manufacturing technologies provide many advantages among industrial sectors. Most applications exploit design freedom for functional design enabled by Powder Bed Fusion processes, while Directed Energy Deposition systems are mainly restricted to the construction of large parts and reparation of damaged components. Nevertheless, the latter provide not only high deposition rates, but also high flexibility, and the possibility to process multi-materials, to grade and combine their characteristics for enhanced features and performance. Therefore, a rising application is the remanufacturing of existing components to produce functional design variants. Those parts can integrate different features and materials through direct deposition of metals over bounded areas. This work concerns the development of a Design for Additive Remanufacturing methodology for existing components with improved performances to be produced by the laser-based Direct Metal Deposition process. It relies on the use of CAD platforms for the integrated design of products and the associated processes. The design approach is based on the integration of CAE structural analysis and Topology Optimization, to define the location and the morphology of deposited structures. The design of an automotive suspension arm with enhanced performances is the use case to demonstrate the effectiveness of the approach, which could be extended to the remanufacturing of several bodies and chassis automotive subsystems.

Keywords: Design for Additive Manufacturing , Finite Element Analysis , Hybrid Manufacturing , Laser Metal Deposition , Remanufacturing , Topology Optimization

The present paper develops an analytical methodology to design electrical powertrains and to study the performance of multirotor configurations. The model is based on the general momentum and blade element theories and it has been modified to take into account for multiple rotors and vertical flight conditions. An iterative procedure to design battery packs and compute the discharge time is provided. The original contribution of the article is represented by the application of the above-mentioned methodology to design and compare different eVTOL vehicles against a reference lightweight helicopter with specified design features. As a result, a quadrotor configuration is identified as the best solution to fulfill all the mission requirements and improve the performance of the helicopter with additional benefits.

Keywords: battery design , eVTOL , helicopter , mission design , multirotor , performance analysis , side-by-side

This research concerns the optimization study of the wing of an ultralight competition sailplane, category F5J/F3J. Fundamental for this category is the characteristic of lightness associated with good wing stiffness (bending/torsional). All the elements composing the wing of the sailplane were modelled in 3D by using the Autodesk Inventor parametric solid modeler. They were assembled in the FEM environment and were suitably constrained and studied from a structural point of view. The structural characteristics of the wing and its components were analysed in detail after assigning the materials currently used and adopting appropriate materials to make the same with the Additive Manufacturing (AM) technic. A topological optimization, performed by using the Simplex Method (SIMP), was conducted on the internal structure of the wing in order to lighten the ribs with the same performance. The experimental investigations implemented in the laboratory allowed the 'Oralight' material used for the wing surface coating to be characterized. It is an extremely thin and light material, whose elasticity and strength were accurately assessed in this study. The data obtained, considered along with the elasticity and the resistance values of the other materials constituting the wing structure, taken from the literature, were inserted into the finite element simulations with the aim of evaluating the torsional and bending stiffness of the wing. Finally, the rib was redesigned using a FDM material which makes construction particularly simple.

Keywords: Oralight Coating Surface , Compound Bio-Plastic Filament , Ribs and Spars' Redesign , Torsional and Bending Wing Stiffness , Wing Parametric Modelling

Background: The “drive by wire” mechanism for managing the throttle is not applied to every modern motorcycle, but it is often managed through a steel wire. Here, there is a cam on the throttle control. Its shape allows the throttle opening to be faster or slower and its angle of rotation, required for full opening, to be greater or less. The maximum angle a rider's wrist can withstand depends on numerous musculoskeletal mobility factors, often limited by falls or surgery. Methods: Using a Progrip knob with interchangeable cams allows the customization of a special cam profile, to ensure the best engine response to throttle rotation and ergonomics for the rider. The use of FEA software and lattice structures, allows to realize a lightweight and efficient design, targeted for fabrication with additive manufacturing technologies. Results: The cam was manufactured by exploiting MSLA technology. Finally, a dimensional inspection procedure was performed before assembly. The main result is to have obtained a lighter and cheaper component than the original. Conclusions: This study has allowed the design of a mechanical component consisting of innovative shape, light weight, and ergonomics. Furthermore, it demonstrates the effectiveness in the use of lattice structures to enable weight optimization of a component while minimizing the increase in its compliance.

Keywords: CAD/CAM , Design for additive manufacturing , lattice structure , MSLA , nTopology , Shape optimization , Stereolithography tooling , water washable resin

This paper investigates improving the quality of the energy used in the railway field. Due to structural aspects, the railway substations of the high-speed lines generate a voltage imbalance, polluting the electric power. To solve this unbalance problem, a new structure of unbalance compensation based on the concept of impedance controller by Ac-chopper was introduced. This new strategy's dimensioning and control were based on real data provided by the Moroccan national railway operator ONCF. To prove that this solution has a significant impact on the treatment of the unbalance phenomenon and that the CCI compensator behaves like an Eco-design due to its constitution and the reduction of power losses, a comparison was established with the topologies using a Voltage Source Inverter (VSI) and Current Source Inverter (CSI) in terms of energy loss in the semi-conductors; the modelling of the three structures was performed under the MATLAB Simulink environment. The results showed that the CCI compensator is more efficient in limiting the unbalance problem than the other compensators (VSI and CSI). © 2022 Praise Worthy Prize S.r.l.-All rights reserved.

Keywords: Concept of AC-Chopper Controlled Impedance , Optimization Electric Power , Railway , STATCOM