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Nanocellulose derived from plant cell wall, due to its unlimited sources, is regarded as a next-generation green material for the automotive industry because of its high tensile strength (≥3 GPa), high elasticity modulus (110–220 GPa), and low density (1.6 g/cm3). This study first introduces the structural characteristics, preparation techniques, and mechanical properties of nanocellulose. Then, three types of nanocellulose composites, including nanocellulose directly reinforced polymers, hybrid fiber-cellulose composites, and all cellulose composites (ACCs), are reviewed. The corresponding preparation techniques, material properties, reinforcement mechanisms of nanocellulose, and application limitations are discussed in detail. To overcome the insufficient mechanical properties of nanocellulose directly reinforced polymers and ACCs toward the manufacture of automobile structural components, self-assembly techniques prove to be effective to prepare macroscopic fibers by first aligning nanocellulose and then assembling them into continuous micro-size fibers. We reviewed different self-assembly techniques and multiscale modeling techniques of cellulose nanofibers (CNFs) assembled microfibers. Furthermore, we proposed a finite element or finite volume technique-based micromechanics framework to predict the homogenized responses of CNFs assembled microfibers, which serve as a fundamental layer to construct a multiscale modeling strategy toward CNFs assembled microfiber-based composite structures. The proposed multiscale modeling strategy is expected to greatly facilitate the development of CNFs assembled microfiber-based composite structures and significantly advance the application of nanocellulose in automotive structural applications.

In this study, we aimed to reveal the effective reusability of waste generated during the injection molding process of polyamide 66 (PA66) reinforced with 30 wt% of short glass fiber (PA66-GF30) widely used in the automotive industry. PA66-GF30 was subjected to the three mechanical recycling cycles, including regranulation and reinjection molding steps, and the recycled materials obtained in each of these cycles were included at the ratios of 15, 20, 25, and 30 wt% to the virgin composite. Thermogravimetric analysis and differential scanning calorimeter analyses showed that the number of recycling cycles and recycled material content in the composite had no significant change in the thermal stability and crystallinity degree of the PA66-GF30. The average fiber length determined by optical microscope analysis shifted to lower values from 300–350 to 150–250 μm by increasing the number of recycling cycles and the recycled material content. The fact that the recycled material content in the composite exceeds 25 wt% and the recycling cycle is applied three times played a key role in changing the mechanical and melt flow behaviors of the composite. Tensile strength, elastic modulus, and impact energy slightly decreased while the elongation at break and melt flow index increased.

AbstractWear phenomenon impact the operating efficiency and service life of engineering materials due to the influence of surface interaction at different working conditions. Successive tribological studies on wear-resistant materials in the last decade is estimated at approximately 40% of friction and wear, including laboratory tests. Most locally improvised wear testers in accordance with American Society for Testing and Materials (ASTM) and European (EN) standards, though, achieve 95–97% parametric accuracies with reduced cost, they hardly harmonize degradation and Archards coefficients for all possible wear factors, providing little data for simulation of mechanical and chemical wears which are responsible for non-uniform aggregation of wear patterns in practice. Complexities of intermeshing factors which combine to influence the effectiveness of developed test devices span over loads, speeds, temperatures, pressures, and ambience for various applications. This study highlights the techniques of wear characterization, test standards, and wear reduction with emphasis on surface texturing for improved eta/beta phase re-arrangements at low working temperatures in the enhancement of grain contraction during high bias-voltage cathodic substrate multi-phase coating, phosphating during pretreatments using peening techniques, residual stress reduction during cryogenic heat treatments as well as the impact of suitable architectural matrix composite strengthening, microstructures, and material reinforcements as suitable factors to influence improved tribological behaviors in materials. Optimal additive manufacturing (AM‐fabricating) techniques with pretreatments, thermal cycling, and tempering can engineer enhanced anti-tribocorrosion in automotive components.

Hot deformation and in-die quenching of aluminum components for the automotive industry is a cost and energy efficient technique that has been developed and thoroughly evaluated in recent years. The performance of this process is considered higher when compared to traditional cold metal forming due to shorter process times, low-cost machinery, and a high level of structural integrity in fabricated parts. The work presented in this paper provides several approaches for the formability of age hardenable 6xxx alloy sheets when forming at different temperatures. Warm tensile testing and formability cup testing were carried out to investigate the alloy formability at different temperatures. The results indicate that the formability of candidate alloys is not significantly affected by deformation temperatures or conditions, which provides great freedom when designing an automated production process with high productivity and minimal environmental impact. The candidate alloy can be deep drawn without severe thinning at the whole temperature range, from room temperature (RT) to solutionizing temperature. [ABSTRACT FROM AUTHOR]

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to model carbon footprint, carbon dioxide sequestration, and emissions from kenaf cultivation as well as utilization of core and bast as biomaterials in the automotive industries and their environmental implications. It also considers the selection of suitable processing methods to improve the environmental performance of automotive parts. The data were obtained from three areas, and each area was divided into three cultivated sub areas for the carbon footprint model. Data regarding the conversion of kenaf to fibre when using kenaf high decorticator machines were provided from Kenaf Processing and Marketing Centre (CMPC) in Malaysia. The results showed that the total estimated quantity of carbon footprint of kenaf cultivation in the studied areas as well as the farms was about 0.750 tonne CO2/tonne. In addition, the total estimated quantity of carbon sequestration of automotive components in the studied states as well as the district was approximately 180,000 tonne CO2/tonne/hectare/year in addition to carbon sequestered by soil in hectare of cultivated kenaf. The practices of kenaf cultivation, processing, and utilization into automotive components is essential for the environment and will assist in the mitigation of climate change risks.

The fundamental problems with component production in the automotive industry are the low quality of the components, the high number of failures, and the subsequent number of complaints. The quality of automotive components is a prerequisite for automated production in a SMART Factory 4.0 in the context of Industry 4.0. Managing complaints is a critical area in the automotive manufacturing industry. The primary goal of this article is to indicate the significance of a CRM system and the importance of complaints management in automotive manufacturing, which improves the quality of the process of producing components while improving the quality of the inputs—the quality of materials, the quality of the human factor, and the quality of the services provided in connection with the components. (1) A Slovak company was selected as the subject of this research, which focuses on the production of automotive parts. (2) The methods of research focused on using economic analysis and instruments of quality management such as the QRQC method, FMEA method, the Ishikawa diagram, and the Pareto analysis and Lorenz curve. This article presents the results of complaints about automotive components: locksets in vehicles. (3) This research shows the basic cause of the problem: a bent pin after riveting in the process of producing the components. In the frame of this research, we suggested corrective measures to eliminate the actual causes of failure in the production of the components. The RPN index reached a level below the limit of 150 (the critical level of the customers' requirements) after implementing the corrective measures. The total costs of complaints in this year were calculated to be EUR 13.575 and the costs will be reduced gradually after changes are implemented in the production process. (4) A new complaints information system and a new training center are beneficial for solving problems in the production of automotive components. The implementation of a CRM system and other systems are prerequisites for solving customer complaints. [ABSTRACT FROM AUTHOR]

This study aimed to model carbon footprint, carbon dioxide sequestration, and emissions from kenaf cultivation as well as utilization of core and bast as biomaterials in the automotive industries and their environmental implications. It also considers the selection of suitable processing methods to improve the environmental performance of automotive parts. The data were obtained from three areas, and each area was divided into three cultivated sub areas for the carbon footprint model. Data regarding the conversion of kenaf to fibre when using kenaf high decorticator machines were provided from Kenaf Processing and Marketing Centre (CMPC) in Malaysia. The results showed that the total estimated quantity of carbon footprint of kenaf cultivation in the studied areas as well as the farms was about 0.750 tonne CO2/tonne. In addition, the total estimated quantity of carbon sequestration of automotive components in the studied states as well as the district was approximately 180,000 tonne CO2/tonne/hectare/year in addition to carbon sequestered by soil in hectare of cultivated kenaf. The practices of kenaf cultivation, processing, and utilization into automotive components is essential for the environment and will assist in the mitigation of climate change risks. [ABSTRACT FROM AUTHOR]

The development of automotive components with reduced greenhouse gas (GHG) emissions is needed to reduce overall vehicle emissions. Life Cycle Engineering (LCE) based on Life Cycle Assessment (LCA) supports this by providing holistic information and improvement potentials regarding eco-efficient products. Key factors influencing LCAs of automotive components, such as material production, will change in the future. First approaches for integrating future scenarios for these key factors into LCE already exist, but they only consider a limited number of parameters and scenarios. This work aims to develop a method that can be practically applied in the industry for integrating prospective LCAs (pLCA) into the LCE of automotive components, considering relevant parameters and consistent scenarios. Therefore, pLCA methods are further developed to investigate the influence of future scenarios on the GHG emissions of automotive components. The practical application is demonstrated for a vehicle component with different design options. This paper shows that different development paths of the foreground and background system can shift the ecological optimum of design alternatives. Therefore, future pathways of relevant parameters must be considered comprehensively to reduce GHG emissions of future vehicles. This work contributes to the methodological and practical integration of pLCA into automotive development processes and provides quantitative results. [ABSTRACT FROM AUTHOR]

An extension of the dynamic capabilities model is evaluated in a rapidly changing and complex context: the global automotive sector. This industry is undergoing significant change to improve sustainable performance (e.g., alternative power train technologies with less pollution and better energy performance) responding to more stringent regulations and changing locus of innovation (i.e., suppliers investing more in R&D). Using a comparative and validated sample of 104 R&D projects in the U.S. and China, five hypotheses are tested and supported: 1) dynamic capabilities are significantly related to R&D project success, mediated by strategic intent (H1); 2) dynamic capabilities and resources operate independently and significantly in a model to predict sustainable R&D project success (H2); 3) for the U.S. data (a mature economy), there is a significant relationship between technology novelty and dynamic capabilities (H3), but not for the Chinese data, as predicted (H4); and 4) the Chinese economy does not experience the slowdown encountered in the U.S. economy (H5), but Chinese R&D is dominated by incremental improvements of existing products. These results sustain and clarify the differences in the dynamic capabilities model in mature and emerging economies for the global automotive industry. [ABSTRACT FROM AUTHOR]

Wear phenomenon impact the operating efficiency and service life of engineering materials due to the influence of surface interaction at different working conditions. Successive tribological studies on wear-resistant materials in the last decade is estimated at approximately 40% of friction and wear, including laboratory tests. Most locally improvised wear testers in accordance with American Society for Testing and Materials (ASTM) and European (EN) standards, though, achieve 95-97% parametric accuracies with reduced cost, they hardly harmonize degradation and Archards coefficients for all possible wear factors, providing little data for simulation of mechanical and chemical wears which are responsible for non-uniform aggregation of wear patterns in practice. Complexities of intermeshing factors which combine to influence the effectiveness of developed test devices span over loads, speeds, temperatures, pressures, and ambience for various applications. This study highlights the techniques of wear characterization, test standards, and wear reduction with emphasis on surface texturing for improved eta/beta phase rearrangements at low working temperatures in the enhancement of grain contraction during high bias-voltage cathodic substrate multi-phase coating, phosphating during pretreatments using peening techniques, residual stress reduction during cryogenic heat treatments as well as the impact of suitable architectural matrix composite strengthening, microstructures, and material reinforcements as suitable factors to influence improved tribological behaviors in materials. Optimal additive manufacturing (AM-fabricating) techniques with pretreatments, thermal cycling, and tempering can engineer enhanced anti-tribocorrosion in automotive components. [ABSTRACT FROM AUTHOR]

Hot deformation and in-die quenching of aluminum components for the automotive industry is a cost and energy efficient technique that has been developed and thoroughly evaluated in recent years. The performance of this process is considered higher when compared to traditional cold metal forming due to shorter process times, low-cost machinery, and a high level of structural integrity in fabricated parts. The work presented in this paper provides several approaches for the formability of age hardenable 6xxx alloy sheets when forming at different temperatures. Warm tensile testing and formability cup testing were carried out to investigate the alloy formability at different temperatures. The results indicate that the formability of candidate alloys is not significantly affected by deformation temperatures or conditions, which provides great freedom when designing an automated production process with high productivity and minimal environmental impact. The candidate alloy can be deep drawn without severe thinning at the whole temperature range, from room temperature (RT) to solutionizing temperature.

This paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching, the switching frequency was set to 150 kHz. A laboratory prototype was built to verify the properties and operating principles of the described charger topology. The on-board charger has been tested in a microgrid test platform. Due to the parasitic properties of the transformer and other electronic components, overvoltage with subsequent oscillations occurred on the primary side of the transformer and damped resonance on its secondary side. These parasitic properties caused interference and especially voltage stress on the semiconductor elements. These undesirable phenomena have been eliminated by adding an active element to the charger topology and a new transistor control strategy. This new switching control strategy of transistors has been patented. [ABSTRACT FROM AUTHOR]

Continuous optimization of processes and products in automotive companies is necessary. The costumers' demand is growing, making it necessary to increase the number of orders and reduce deadlines. All these changes showed that the processes used in the past are outdated and innovation is needed. Nonetheless, it is not viable to increase manpower or number of production lines without improving and optimizing the existing processes. This work aims to analyse and improve the efficiency of a stamping process of an automotive components' manufacturer, arising due to the low overall equipment effectiveness (OEE) of transfer dies. Under this scenario, the transfer system should be modified to decrease the setup time and production stoppage, by producing a design that reduces the setup time at the time of changing components/specifications of the fabricated parts or changing the stamping tool. Several management tools were applied, such as failure mode and effects analysis (FMEA analysis) in the pre-design phase. A new concept was devised for the transfer system to increase its stability. The new design accomplished a significant reduction of setup times and production stops, and also a major weight reduction, leading to higher reliability. [ABSTRACT FROM AUTHOR]

Unlike other counterfeit products, automotive components are hidden from view and, at least by the lay person, little understood. While the potential scale, scope and impact of the problem is vast, knowledge of this illicit trade is limited. In seeking to contribute to the existing literature on the counterfeiting of auto components, this article focuses on China, a major and growing economy with an expanding vehicle market, a ready internal market for counterfeits and a frequently identified source country of counterfeit goods. Rested upon empirical data from published court judgments in China and open source materials, this article critically explores the counterfeiting of motor vehicle parts inside the country, from manufacture to sale, including identifying the parties involved in the illegitimate business, the counterfeiting process and what motivates the players to engage in it, to gain insights into the social organisation of the illicit trade. Our findings suggest that the trade in counterfeit automotive components does not appear robust from an organisational viewpoint, which tends to be carried out by individuals on the basis of necessity and opportunity rather than authority and formal rationality. The article's findings forge a link between counterfeiting and social inequality and help argue that given the current socio-economic settings and a booming market of used vehicles, the dirty economy is likely to persist. Furthermore, as the empirical data shows, currently, the nature of the trade in dangerous counterfeit goods is not duly recognised in law enforcement and legal practices. [ABSTRACT FROM AUTHOR]

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fundamental problems with component production in the automotive industry are the low quality of the components, the high number of failures, and the subsequent number of complaints. The quality of automotive components is a prerequisite for automated production in a SMART Factory 4.0 in the context of Industry 4.0. Managing complaints is a critical area in the automotive manufacturing industry. The primary goal of this article is to indicate the significance of a CRM system and the importance of complaints management in automotive manufacturing, which improves the quality of the process of producing components while improving the quality of the inputs—the quality of materials, the quality of the human factor, and the quality of the services provided in connection with the components. (1) A Slovak company was selected as the subject of this research, which focuses on the production of automotive parts. (2) The methods of research focused on using economic analysis and instruments of quality management such as the QRQC method, FMEA method, the Ishikawa diagram, and the Pareto analysis and Lorenz curve. This article presents the results of complaints about automotive components: locksets in vehicles. (3) This research shows the basic cause of the problem: a bent pin after riveting in the process of producing the components. In the frame of this research, we suggested corrective measures to eliminate the actual causes of failure in the production of the components. The RPN index reached a level below the limit of 150 (the critical level of the customers’ requirements) after implementing the corrective measures. The total costs of complaints in this year were calculated to be EUR 13.575 and the costs will be reduced gradually after changes are implemented in the production process. (4) A new complaints information system and a new training center are beneficial for solving problems in the production of automotive components. The implementation of a CRM system and other systems are prerequisites for solving customer complaints.

The robotic milling of automotive casting components can effectively reduce human participation in the production process and enhance production efficiency and quality, but the premise addresses the reasonable planning of machining paths. To address major challenges, this paper proposes a spatial path planning method for the robotic milling of casting flash and burrs on an automotive engine flywheel shell based on the optimal machining posture. Firstly, an improved stereolithography slicing algorithm in arbitrary tangent plane direction is put forward, which solves the problem that the existing stereolithography slicing algorithm cannot accurately extract the contour of complex components. Secondly, the contour path curve fitting of the slicing points of the flywheel shell is realized based on the B-spline curve. Next, a machining posture evaluation function is established based on the robot's stiffness performance, and the optimal machining posture is solved and verified with simulation according to the machining posture evaluation function and posture interpolation. Finally, the experiments indicate that the proposed method can significantly enhance the machining quality, with an average allowance height of 0.33 mm, and reduce the machining time to 9 min, compared with the conventional manual operation, both of which satisfy the machining requirements. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) is applied to manufacture a Ti–6Al–4V conrod, an engine component, in order to reduce the weight respect to the original version produced by forging with the same alloy. The weight reduction is achieved through a topological optimization and is about 15%. The article focuses on an experimental study of titanium SLM and hot forging components based on evaluation and comparison of properties relevant for automotive applications: metallurgy, corrosion behavior, and wear resistance. The microstructure is duplex, composed of equiaxial α and β grains for both the technologies analyzed; different morphology and distribution of α and β phases are observed as expected. The analysis on corrosion and wear resistance against 100Cr6 highlights very similar properties for the two technologies. Finally, this study confirms that Ti–6Al–4V made by SLM can substitute the traditional forging technologies in the transport field for the properties here studied. [ABSTRACT FROM AUTHOR]

Determining driver situational awareness is one of the most difficult tasks in driver performance profiling. Perception, being the first level of driver situational awareness, is perhaps the only objectively quantifiable factor for driver inattention detection. In the context of this paper, driver perception is defined as their ability to understand their operating environment and peripheral contextual information. One of the most reliable means of determining driver perception is through eye tracking and gaze concentration. In this study, a set of carefully chosen in-vehicle gaze targets are used to determine driver gaze concentration on/off the road. The time drivers spend looking at these predefined gaze targets has been used to characterise driver visual behaviour at roundabouts during normal driving. In total, 24 drivers completed a 22 km route, including two 5-exit two-lane roundabouts in urban and suburban traffic. This study shows that on the approach to roundabouts, driver gaze direction and gaze concentration was often diverted away from the direction of travel of the vehicle and for some drivers it took a significant amount of time to return their gaze towards the direction of travel of the vehicle. The study is based on the premise that a driver not looking at key regions in a scene cannot perceive the contents of those regions with sufficient detail for safe driving. It is not possible to determine a driver’s level of understanding of a scene, unless the parameters of the scene as well as the driver’s response is determined in real time. [ABSTRACT FROM AUTHOR]

Biodiesel is an alternative renewable resource to petroleum-based diesel. The aim of using biodiesel is to reduce environmental pollution and combat global warming. Biodiesel application in compression ignition engines has shown its compatibility with better combustion characteristics and high engine performance. Many advantages can be obtained by using biodiesel, including reducing exhaust gases, reducing air toxicity, providing energy security, and being biodegradable. However, biodiesel’s disadvantage involves oxidation stability, corrosion, degradation, and compatibility with other metallic materials. The present study investigates the corrosive behavior of the ternary blend (waste cooking-Calophyllum inophyllum biodiesel-diesel) fuel that occurs in contact with mild steel and stainless steel 316. The observation study for mild steel and stainless steel 316 material under the static immersion method was performed for 7,200 h and 14,400 h, respectively, at room temperature (25°C–30°C). In every 720 and 1,440 h of immersion time, the coupon’s profile was analyzed by scanning electron microscopy (SEM)/electron-dispersive spectrometer (EDS), and the mass loss was observed, for corrosivity investigation. Based on the obtained results, the average corrosion rate of mild steel and stainless steel 316 is 0.6257 and 0.0472 nm/year at 7,200 h, respectively; the difference in corrosion rate for these metallic materials is approximately 92.46%. The degradation of the fuel properties such as kinematic viscosity, density, refractive index, and acid value was monitored. In this study, stainless steel 316 was more resistant to corrosion attack with some micro pitting and showed better compatibility with the ternary blend than mild steel. The regression analysis and the correlation of corrosion rate were studied.

This paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching, the switching frequency was set to 150 kHz. A laboratory prototype was built to verify the properties and operating principles of the described charger topology. The on-board charger has been tested in a microgrid test platform. Due to the parasitic properties of the transformer and other electronic components, overvoltage with subsequent oscillations occurred on the primary side of the transformer and damped resonance on its secondary side. These parasitic properties caused interference and especially voltage stress on the semiconductor elements. These undesirable phenomena have been eliminated by adding an active element to the charger topology and a new transistor control strategy. This new switching control strategy of transistors has been patented.

Selective laser melting (SLM) can be used to manufacture near net shape (NNS); the main benefits are a remarkable weight reduction, a lower environmental impact, the opportunity to integrate some functions, and an improvement of the performances. The current article covers the development of a Ti6Al4V NNS engine component produced by SLM. Finite element analyses of the main relevant operating conditions are performed to reach a topological optimization of the part. The main target is weight reduction keeping the same safety performances. The weight reduction achieved is 45% and 15% with respect to steel and titanium forging by replacing the original "H" section with an SLM multibranch structure. Other benefits are the manufacturing of the connecting rod (conrod) into two separate parts, avoiding the difficult machining to separate the cap from the main body and the integration of conformed cooling channels into the conrod. Then, the SLM components are produced and mechanical and metallurgical properties are investigated and compared with the titanium hot forging ones. Both the macrostructures present equiassic and isotropic behavior due to the heat treatment transformation. No defects are observed for both the technologies. The mechanical properties are verified to be aligned with the design targets. [ABSTRACT FROM AUTHOR]

The rapid development and popularization of video surveillance highlight the critical and challenging problem, vehicle reidentification, which suffers from the limited interinstance discrepancy between different vehicle identities and large intrainstance differences of the same vehicle. In this article, we propose a novel multilevel attention network to hierarchically learn an efficient feature embedding for vehicle re-ID. Three kinds of attention are designed in the network: hard local-level attention to localize vehicle salient parts, soft pixel-level attention to refine attended pixels both globally and locally, and spatial attention to enhance the encoder's spatial awareness of salient regions within the windscreen area. Multigrain features are subsequently learned from semantic awareness to spatial awareness, guaranteeing the intraclass compactness and interclass separability for vehicle re-ID. Extensive experiments validate the effectiveness of each attention component and demonstrate that our approach outperforms the state-of-the-art re-ID methods on two challenging datasets: VehicleID and Vehicle-1 M. [ABSTRACT FROM AUTHOR]

The robotic milling of automotive casting components can effectively reduce human participation in the production process and enhance production efficiency and quality, but the premise addresses the reasonable planning of machining paths. To address major challenges, this paper proposes a spatial path planning method for the robotic milling of casting flash and burrs on an automotive engine flywheel shell based on the optimal machining posture. Firstly, an improved stereolithography slicing algorithm in arbitrary tangent plane direction is put forward, which solves the problem that the existing stereolithography slicing algorithm cannot accurately extract the contour of complex components. Secondly, the contour path curve fitting of the slicing points of the flywheel shell is realized based on the B-spline curve. Next, a machining posture evaluation function is established based on the robot’s stiffness performance, and the optimal machining posture is solved and verified with simulation according to the machining posture evaluation function and posture interpolation. Finally, the experiments indicate that the proposed method can significantly enhance the machining quality, with an average allowance height of 0.33 mm, and reduce the machining time to 9 min, compared with the conventional manual operation, both of which satisfy the machining requirements.

A state-of-the-art real-time rain detection and wiper control method is proposed in this article. Currently, commercial models adopt electronic sensors that can only sample the humidity of a small region of the windshield. The existing computer vision methods primarily focus on the detection and counting of raindrops and provide a recall rate of less than 70%. Here we adopted a holistic-view deep learning approach to build a visual classifier that is robust to large varieties of background scenes, illumination, and water forms. Specifically, Deep Residual Network (ResNet) was adopted as the visual classifier that distinguishes between rainy and fair street scenes and controls the wipers accordingly. To verify the practicality of the proposed deep learning framework, we tested the network on various embedded computing systems, including an embedded computing cluster. The results show that the deep learning rain detector outperforms previous state-of-the-art methods with higher rain recall and precision. It was also found that with the help of some graphic computation-enhancing components, commonly available embedded systems in the market can provide comparable performance to personal computers. While using the enhanced embedded systems to build a cluster, a performance superior to PC was witnessed. As the embedded system is cost-effective, small, and lighter, normalized performances for various aspects clearly show the competitive edge of the embedded systems and confirm the practicality of the proposed system. We also release the dataset of 160 k images used for training the visual rain detector. [ABSTRACT FROM AUTHOR]

Novel manufacturing techniques and application of new hybrid materials in the automotive industry increase the challenges in adhesive bonding. One of these is the bonding of coated materials such as high-strength steel with an aluminum-silicon (AlSi) coating, which is mostly used in safety-relevant components such as the front or side bumpers. To further improve the mechanical properties, these steel structures can be locally reinforced with a fiber-reinforced compression molding compound (SMC). In this process, the SMC is pressed directly onto the structure, without any pre-treatment of the surface of the steel, whereby the thermosetting resin matrix forms an adhesive bond with the AlSi coating. The choice of a suitable base resin system is of decisive importance for the joint strength of such directly joined hybrid composites and thus also for the overall performance. Therefore three SMC formulations with different base resins were tested for direct adhesion to a metallic surface of a hot-formed steel with an AlSi coating. The aim of this investigation is to identify a correlation between energetic as well as optical surface characteristics and the mechanical strength of such direct hybrid joints. Furthermore, it shall be examined whether a modification of the base resin in the polymer has a significant influence on the bonding strength and the fracture pattern. For this, the project focuses on new methods for the mechanical testing of metal-plastic hybrid composites. [ABSTRACT FROM AUTHOR]

The physical bottleneck of optical design and the complexity associated with the human visual system (HVS) limits the true potential of the head-up display (HUD) for use in vehicles. A full windscreen of visual information feedback is required for driving safety, and its implementation to enhance the driving experience is one of the most significant challenges. We present an immersive augmented reality (AR) HUD concept to support future vehicle design following a human-centric design approach. The limited field of view of contemporary optical solutions can be overcome by multiple display elements tiled to utilize images over the entire windscreen and so create an immersive experience. The design takes important human factors into account and improves the operator’s driving experience. Furthermore, the images are “distributed,” meaning that the physical interface generates the images via multiple optical apertures/image sources and displays these images according to HVS requirements. These configurations are tested in a laboratory environment with a replica of a real car interior and a prototype vehicle installed with distributed multiple HUD units. The proposed concept of an immersive human-machine interface (HMI) can be further extended in various forms to other parts of the vehicle interior, including surfaces and free space, which we envisage will take place in future car designs. [ABSTRACT FROM AUTHOR]

The present work relates to devising a decision-making framework to select suitably the best material alternative for the production of automotive parts produced through the high-pressure die casting process. The problem has been addressed keeping in view the quintessential aspects of sustainability and energy efficiency in the metal casting process. The presented decision-making approach has the potential ability to handle the uncertainty and vagueness concurrently with the fluctuations in the data for a given phase of time. These have been incorporated through the conceptual framework of the complex interval-valued intuitionistic fuzzy model. Moreover, the psychological behavior of the decision-maker toward risk perspective has also been given due consideration in the devised decision-making framework through the TOmada de Decisao Interativa Multicriterio (TODIM) method based on cumulative prospect theory approach. The proposed approach has been referred to as the complex interval-valued intuitionistic fuzzy TODIM approach. A total of three material alternatives have been evaluated under the influence of eighteen conflicting criteria. Aluminum turns out to be the best material alternative, while on the other hand magnesium alloy was revealed to be the worst-performing among considered materials. Sensitivity analysis revealed the robustness of the ranking results, emphasizing the importance of the risk appetite of the decision-maker. Comparative analysis reveals a strong correlation between the ranking results and hence the validity. The decision-making approach therefore can be employed to promote sustainable engineering practices by minimizing the material wastage in other energy-intensive manufacturing processes. [ABSTRACT FROM AUTHOR]

In this letter, we present a hybrid optimization method for the synthesis of distributed array consisting of two identical subarrays, which is mainly used on aeroplanes as the front end of communication system, aiming to lower the grating lobe level as much as possible. The proposed method is on the basis of a combination of differential evolution optimization and weighted ${l_1}$ convex optimization. In the procedure of optimization, a hybrid method of optimization is proposed to optimize element positions and excitations to obtain the optimum performance, while multiple constraints are adopted to satisfy the application requirements. Numerical comparisons between different values of parameters are presented to assess the effectiveness of the proposed optimization method, showing the best result of optimization possibly obtained with different parameters. [ABSTRACT FROM AUTHOR]

Shoulder exoskeletons potentially reduce overuse injuries in industrial settings including overhead work or lifting tasks. Previous studies evaluated these devices primarily in laboratory setting, but evidence of their effectiveness outside the lab is lacking. The present study aimed to evaluate the effectiveness of two passive shoulder exoskeletons and explore the transfer of laboratory-based results to the field. Four industrial workers performed controlled and in-field evaluations without and with two exoskeletons, ShoulderX and Skelex in a randomized order. The exoskeletons decreased upper trapezius activity (up to 46%) and heart rate in isolated tasks. In the field, the effects of both exoskeletons were less prominent (up to 26% upper trapezius activity reduction) while lifting windscreens weighing 13.1 and 17.0 kg. ShoulderX received high discomfort scores in the shoulder region and usability of both exoskeletons was moderate. Overall, both exoskeletons positively affected the isolated tasks, but in the field the support of both exoskeletons was limited. Skelex, which performed worse in the isolated tasks compared to ShoulderX, seemed to provide the most support during the in-field situations. Exoskeleton interface improvements are required to improve comfort and usability. Laboratory-based evaluations of exoskeletons should be interpreted with caution, since the effect of an exoskeleton is task specific and not all in-field situations with high-level lifting will equally benefit from the use of an exoskeleton. Before considering passive exoskeleton implementation, we recommend analyzing joint angles in the field, because the support is inherently dependent on these angles, and to perform in-field pilot tests. This paper is the first thorough evaluation of two shoulder exoskeletons in a controlled and in-field situation. [ABSTRACT FROM AUTHOR]

This study investigates an integrated wheel slip, yaw rate, and sideslip angle control via torque vectoring to improve both the longitudinal and lateral stability of electric vehicles (EVs) with four in‐wheel motors. The algorithm is developed based on model predictive control (MPC) and thus can optimally reach a balance among different objectives while considering actuation and state constraints. Firstly, to deal with tyre non‐linearity and variations in the lateral tyre forces due to changes in tyre slip ratios, the mechanism of using torque vectoring to improve vehicle stability is analysed. Then, a non‐linear tyre model is introduced into the predictive model to characterise the tyre force coupling relationship. Here, a linear‐parameter‐varying (LPV) model is employed, which is derived by linearising the nonlinear vehicle model online. Moreover, the stability control of EVs with in‐wheel motors is transformed into a constrained online optimisation problem and solved using the proposed LPV‐MPC method. Finally, the proposed LPV‐MPC is compared with some existing well‐established techniques from literature in different test scenarios. The obtained results demonstrate that the LPV‐MPC approach could reduce the computational burden and shows a precise longitudinal control and obviously improves the lateral stability. [ABSTRACT FROM AUTHOR]

Based on the electromagnetic induction Hall zero position sensor, a multi-stage reducer motor structure system with a brush DC motor is designed using an aviation fuel on–off valve. The output shaft of the motor structure can respond to commands, rotate double directions, and lock the brake shaft after reaching the designated position. After that, the current position and on/off situation of pipeline fuel can be derived accurately. The system has the advantages of light weight, small volume, fast response, high precision, high reliability, and integration.

Unbalanced body pressure distribution caused by poor sitting posture is a significant factor causing lumbar disease. Research on the dynamic adjustment strategy for comfort sitting posture is of great significance to the prevention and improvement of lumbar disease. In this study, based on the pressure sensor array, the body pressure distribution in different sitting postures are obtained, including: back bow, waist bow, body slip, body right leaning, standard sitting position, and body left leaning. The recognition of the human body posture was achieved using the support vector machine algorithm and the accuracy rate reach to 83.33%. Furthermore, the evaluation indicators for sitting comfort of the human body are proposed using the maximum pressure, average pressure, maximum pressure gradient, average pressure gradient and asymmetry coefficient, the accuracy of the above indicators were verified using semantic differential subjective evaluation method. Experimental results show that there is a strong positive correlation between objective indicators and seat comfort. In addition, the dynamic adjustment strategy using airbag base on seat comfort evaluation is studied.

In recent years, improvement in multi-material additive manufacturing technology has resulted in technical improvements in multi-material design employed by the automotive industry. Therefore, in this work, an internal trim part (corresponding to an original product composed of polypropylene) of a vehicle was divided into four components using a multi-material design method considering PLA composites. The PLA was reinforced with basalt fibers for realization of the required mechanical properties. The mechanical properties associated with different fiber content (from 0 to 60%) were determined via tensile tests. To reduce the mass of the product, an optimization process combining a Kriging surrogate model with a Multi-Island Genetic Algorithm was used to search for the Pareto solution. The coefficient of determination (R2) and response surface methodology (RSM) surrogate model were used to confirm the validity and accuracy of the Kriging model. The values of R2 were all >0.92 and the low error value of both results demonstrated the effectiveness of the optimization process. Owing to the optimization process, the mass of the PLA composite product was reduced by nearly 9%. Correlation analysis indicated that x2 has the strongest impact on the total mass. Therefore, the optimization process proposed for the multi-material optimal design is feasible and contributes significantly to the attainment of light-weight vehicle parts.

Based on the electromagnetic induction Hall zero position sensor, a multi-stage reducer motor structure system with a brush DC motor is designed using an aviation fuel on–off valve. The output shaft of the motor structure can respond to commands, rotate double directions, and lock the brake shaft after reaching the designated position. After that, the current position and on/off situation of pipeline fuel can be derived accurately. The system has the advantages of light weight, small volume, fast response, high precision, high reliability, and integration. [ABSTRACT FROM AUTHOR]

This paper is concerned with modelling of the transmissivity of Low-Terahertz waves through automotive bumper and headlight cover material. This work is part of wider comprehensive studies on the potential for the use higher frequency bands for future automotive sensors. Theoretical models for transmissivity prediction are described, the methodology of experimentation is discussed and experimental results are presented. The theoretical models of reflection and transmission of different base materials which are covered by different layers of paint are based on Fresnel theory, and the phenomena caused by the half wavelength thickness of the medium is analyzed mathematically. The experimental verification of the models in this paper have been undertaken at 300 GHz and 670 GHz, using 77 GHz as a reference frequency. [ABSTRACT FROM AUTHOR]

The effects of manufacturing tolerances on the maximum focal temperature has been investigated by transient thermomechanical simulations. Both relative cone angle and cone out-of-roundness for molybdenum and carbon fibre reinforced polymer synchronizers were evaluated. It was shown that cone out-of-roundness significantly increases the focal contact temperature for that specific cone but has little impact on the opposing cone. Two populations of measured synchronizers were evaluated, and it was shown that the maximum focal surface temperature can be decreased in almost all tolerance cases by introducing a relative angle between the cones. [ABSTRACT FROM AUTHOR]

For decades, electric power steering (EPS) systems have replaced hydraulic‐assist steering systems. The main purpose of EPS systems is to generate an assist torque using an electric motor for the improvement of the driving comfort. The proposed controller is designed against a model predictive control (MPC) and linear quadratic regulator (LQR) for a comparison in terms of generating a desired value of the assist torque. The motion equations of a column‐type EPS system are derived in this study. Meanwhile, MPC has been regarded as an effective control method for constrained problems because this method can anticipate future events of the system. However, the repeated online optimisation imposes huge computational complexity. The proposed scheme explicitly obtains the current control law by adopting a multi‐parametric quadratic programming technique. The proposed controller is evaluated in MATLAB/Simulink and a hardware‐in‐the‐loop simulation using the Infineon automotive TriCore AURIX TC277 microcontroller. The simulation and experimental results confirmed that the proposed controller successfully tracks the reference value while reducing the computational burden. It is also shown by conducting experiments with various vehicle speeds that the tracking ability of the explicit model predictive controller (MPC controller) is superior to that of the LQR controller. [ABSTRACT FROM AUTHOR]

Unbalanced body pressure distribution caused by poor sitting posture is a significant factor causing lumbar disease. Research on the dynamic adjustment strategy for comfort sitting posture is of great significance to the prevention and improvement of lumbar disease. In this study, based on the pressure sensor array, the body pressure distribution in different sitting postures are obtained, including: back bow, waist bow, body slip, body right leaning, standard sitting position, and body left leaning. The recognition of the human body posture was achieved using the support vector machine algorithm and the accuracy rate reach to 83.33%. Furthermore, the evaluation indicators for sitting comfort of the human body are proposed using the maximum pressure, average pressure, maximum pressure gradient, average pressure gradient and asymmetry coefficient, the accuracy of the above indicators were verified using semantic differential subjective evaluation method. Experimental results show that there is a strong positive correlation between objective indicators and seat comfort. In addition, the dynamic adjustment strategy using airbag base on seat comfort evaluation is studied. [ABSTRACT FROM AUTHOR]

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The thermal design-analysis of devices with electrical windings impregnated using varnish materials is frequently challenging. This is due to difficulties in predicting theoretically the equivalent thermal properties for the composite materials, such as impregnated windings, in a reliable manner. The existing approach makes use of the impregnation ‘goodness’ factor, which allows for imperfections associated with the winding impregnation to be accounted for. This, however, requires experimentally derived data from appropriate material samples or machine assemblies. Considering relatively large range of commercially available varnishes, such data are often limited and are not readily accessible. In this investigation, a set of three alternative varnish materials commonly used in impregnation of low-voltage electrical windings has been evaluated. To provide better understanding of the material impregnating properties, data from multiple impregnations are also provided. The experimental findings have been supplemented with theoretical analysis on the impregnation ‘goodness’ and stator-winding contact thermal resistance for a selected winding construction. To highlight the importance of appropriate input thermal material data, a case study machine design is thermally analysed.

Composite processing and subsequent characterization of microfibrillar composites (MFC) were the focus of this work. Compression molding of wound MFC filaments was used to fabricate MFC composites. The MFC composites were composed of polypropylene (PP) as matrix materials and polyethylene terephthalate (PET) as reinforcement fibers. The PP/PET blends were mixed with PET contents ranging from 22 wt% to 45 wt%. The effect of processing parameters, pressure, temperature, and holding time on the mechanical properties of the MFCs was investigated. Tensile tests were conducted to optimize the processing parameter and weight ratio of PET. Tensile strength and modulus increased with the increase in PET content. PP/45 wt% PET MFC composites properties reached the value of PP/30 wt% GF. Falling weight tests were conducted on MFC composites. The MFC composites showed the ability to absorb the impact energy compared to neat PP and PP/30 wt% GF.

The thermal design-analysis of devices with electrical windings impregnated using varnish materials is frequently challenging. This is due to difficulties in predicting theoretically the equivalent thermal properties for the composite materials, such as impregnated windings, in a reliable manner. The existing approach makes use of the impregnation 'goodness' factor, which allows for imperfections associated with the winding impregnation to be accounted for. This, however, requires experimentally derived data from appropriate material samples or machine assemblies. Considering relatively large range of commercially available varnishes, such data are often limited and are not readily accessible. In this investigation, a set of three alternative varnish materials commonly used in impregnation of low-voltage electrical windings has been evaluated. To provide better understanding of the material impregnating properties, data from multiple impregnations are also provided. The experimental findings have been supplemented with theoretical analysis on the impregnation 'goodness' and stator-winding contact thermal resistance for a selected winding construction. To highlight the importance of appropriate input thermal material data, a case study machine design is thermally analysed. [ABSTRACT FROM AUTHOR]

The torque density characteristics for an axial flux magnetic gear using a flux‐focusing topology is experimentally studied when using neodymium iron boron (NdFeB) rare‐earth magnets. A geometric parameter sweep analysis was utilised in order to maximise both the calculated volumetric and mass torque density. The calculated torque and torque density was 628.6 N·m and 173.02 N·m/L while the experimentally measured torque and resultant torque density was 553.2 N·m and 152.3 N·m/L. [ABSTRACT FROM AUTHOR]