Car Interior Research Articles

Fabrication of integrated polysilicon waveguides for mid-infrared absorption sensing

Abstract. The increasing popularity of environments equipped with sensors for convenience and with safety features, as in, for example, smart homes, greenhouses, or the interior of modern cars, demands a variety of sensor systems. In this respect, the sensing of ambient gases in the sense of air quality monitoring or leakage detection is one of the prominent applications. However, even though there are many different systems already available, the trend goes towards smaller and rather inconspicuous sensors which are embedded in the environment. We present the fabrication and characterization of integrated waveguides, which constitute an interesting platform for absorption spectroscopy in the mid-infrared (mid-IR) using the evanescent field of guided modes interacting with the analyte, thus leading to the absorption-induced attenuation of the mode. Corresponding simulations, characterizing the efficiency of the desired interaction, predict values for the confinement factor Γ and the intrinsic damping D for a waveguide geometry, which is then characterized by measurements. Furthermore, we discuss how these waveguides could be part of an integrated, non-dispersive, mid-IR sensor system fully integrated on a single chip. In this context, we present a way to maintain the quality of waveguides throughout the entire workflow needed to integrate a pyroelectric IR detector based on aluminum nitride (AlN).

Occurrence, emission sources, and risk assessment of polybrominated diphenyl ethers and current-use brominated flame retardants in settled dust from end-of-life vehicle processing, urban, and rural areas, northern Vietnam.

Settled dust samples from Vietnamese end-of-life vehicle (ELV) processing, urban, and rural areas were analyzed for polybrominated diphenyl ethers (PBDEs) and other current-use brominated flame retardants (BFRs). PBDE levels found in dust samples collected from ELV workshops (median 390; range 120-520ng/g) and nearby living areas (110; 36-650ng/g) were generally higher than those in common house dust (25-170ng/g). BDE-209 was the most predominant congener detected in almost all the samples, indicating extensive application of products containing deca-BDE mixtures. The dust samples from ELV workplaces showed a more abundance of lower brominated congeners (e.g., tetra- to hexa-BDEs) that may originate from car interior materials treated by penta-BDE formulations. Concentrations of other BFRs decreased in the order urban > rural > ELV dust, reflecting the current use of these compounds in new consumer products. Decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) were the major alternative BFRs. Daily intake doses and hazard indexes of PBDEs and some other BFRs through dust ingestion were estimated and showed acceptable levels of risk. However, more comprehensive risk assessment considering multiple exposure pathways should be performed, especially for ELV workers and children in the ELV processing and urban areas.

A new look for car interiors

A range of polypropylene (PP) compounds could help improve the aesthetics of interior automotive parts.

Физико-математическое моделирование процесса взаимодействия подушки безопасности легкового автомобиля с антропоморфным манекеном

The paper considers a finite-element numerical simulation of interaction between an airbag and an anthropomorphic dummy model, presenting a case study of a passenger car subjected to oblique frontal impact, as per UN passive safety Regulation no. 94. A system of conservation equations for mass, impulse and energy forms the basis of the simulation. We used a penalty method as a contact algorithm. We investigated three situations: 1) one including the seat belt and the airbag; 2) one including the belt but not the airbag; 3) one including the airbag without the belt. The airbag simulation took into account the specifics of its deployment process and its position within the steering wheel. The seat belt simulation included simplified models of the retracting and locking devices. The computation results showed that our finite-element numerical simulation of interaction between the airbag and the anthropomorphic dummy model makes assessing the test device injury rate possible; absence of either the seat belt or the airbag may result in death due to oblique frontal impacts; if the design only includes an airbag, collisions between the anthropomorphic dummy model and the interior car parts will not be prevented; a design providing both an airbag and a seat belt meets the basic requirements of UN passive safety Regulation no. 94

Privacy-protection system using a unidirectional emission waveguide liquid crystal display and an asymmetrical transmission window system

Privacy-protection system using a unidirectional emission waveguide liquid crystal display (WG-LCD) with an electrically switchable vertically aligned polymer network LC (VA-PNLC) cell and an asymmetrical transmission window (ATW) system is reported. The configurations and operations of the WG-LCD, the WG-LCD with a VA-PNLC cell, the ATW system, and the privacy-protection system are elucidated. The ATW system comprises an absorption layer (dichroic dyes doped in two LC layers), a common window, and specific light sources. With the use of the privacy-protection system, people in a private space can see the private information displayed on the WG-LCD with the VA-PNLC cell and the scenes in a public space. Contrarily, people in a public space cannot see the scenes in the private space and the displayed information. The methods to increase optical performance of the privacy-protection system, WG-LCD with a VA-PNLC cell, as well as the method of designing the absorption layer with the light sources in a private space are elucidated. The ATW/privacy-protection system can be applied to various fields in daily life, such as car interior space and home/meeting room.

Environmental analysis of a bio-based coating material for automobile interiors

The evolution towards an increasingly more sustainable development and a more circular economy requires the development of materials based on renewable feedstocks, to replace the still dominant non-renewable resources. Several imitation leather materials produced from renewable feedstocks have recently emerged to replace animal or synthetic leathers used in car interiors, with good performance results. However, few Life Cycle Assessment (LCA) studies are available for evaluating the potential environmental impacts of these new materials. Thus, the present study contributes to fill this gap, carrying out an anticipatory LCA (a-LCA) of a new bio-based material, a vegetable leather, intended for coatings in car interiors, produced from olive pomace, an abundant by-product of olive oil production in Portugal. For the life cycle inventory analysis, information from the literature and industrial practice was used, such as information from similar production processes, correlations, or simplistic approximations, in order to obtain an estimate of energy and materials consumption for the new vegetable leather production. Four environmental impact categories were evaluated: Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP) and Photochemical Oxidation Potential (POP). Six scenarios were compared, defined considering the incorporation of different percentages of alkyd resin and polyurethane into the vegetable leather. The calculations were carried out using the openLCA software and considering a “cradle-to-gate” approach. The results show that the new vegetable leather presents significant environmental impacts, being the production of polyethylene terephthalate (PET) mesh fabric the greatest contributor, followed by energy consumption. A recycled PET mesh fabric was also analyzed. It is concluded that despite the bio-based components used, a high percentage of synthetic materials is still required, which leads to higher environmental impacts of the whole material.

Analysing the effect of gender on the human–machine interaction in level 3 automated vehicles

The emergence of the level 3 automated vehicles (L3 AVs) can enable drivers to be completely disengaged from driving and safely perform other non-driving related tasks, but sometimes their takeover of control of the vehicle is required. The takeover of control is an important human–machine interaction in L3 AVs. However, little research has focused on investigating the effect of gender on takeover performance. In order to fill this research gap, a driving simulator study with 76 drivers (33 females and 43 males) was conducted. The participants took over control from L3 AVs, and the timing and quality of takeover were measured. The results show that although there was no significant difference in most of the measurements adopted to quantify takeover performance between female and male. Gender did affect takeover performance slightly, with women exhibited slightly better performance than men. Compared to men, women exhibited a smaller percentage of hasty takeovers and slightly faster reaction times as well as slightly more stable operation of the steering wheel. The findings highlight that it is important for both genders to recognise they can use and interact with L3 AVs well, and more hands-on experience and teaching sessions could be provided to deepen their understanding of L3 AVs. The design of the car interiors of L3 AVs should also take into account gender differences in the preferences of users for different non-driving related tasks.

Electrical applications in Internet of things and e-vehicles: Passive fire safety needs and solutions

The exponential growth of electrical devices in Internet of things and e-vehicles will lead to new fire safety challenges. As electric fires rank second among all fires and electrical equipment recalls show safety gaps, fire safety requirements must be better enforced and improved. The analysis of the current qualitative pass/fail requirements for electrotechnical products shows that they provide a basic level of fire safety. Fire testing of car and bus interiors, mandatory worldwide, is too low level. Alternative tests, such as the microscale combustion calorimeter, are discussed. Buses have to comply with additional fire tests. E-vehicles must meet a fire exposure test for electric powertrain and specifications to prevent thermal runaway of batteries. Charging stations must comply with fire and overheating requirements for enclosures, plugs, and sockets. Passive fire safety needs are primarily met by using flame retardants, and for preventing thermal runaway of batteries, by intumescent coatings, interlayers, and ceramifying products.

Effect of Various Factors on Plant Fibre-Reinforced Composites with Nanofillers and Its Industrial Applications: A Critical Review

The growing awareness of the environmental damage caused by petroleum-based fibres has led to an increase in renewable and biodegradable resources. The continually growing demand for eco-friendly and sustainable materials pushes automakers and material researchers to consider the ecological importance of their materials during fabricating, recovering, and disposal. Natural fibre-reinforced composites (NFRC) have been introduced into the automobile market substantially over the last ten years due to their renewability, eco-friendliness, recyclability, biodegradability, light weight, better specific strength, good resistance to impact and corrosion, abundantly available, ease of processing, and cost-effectiveness. Due to cost-effectiveness and weight reduction, NFRC is becoming a better replacement for petroleum/synthetic fibres like aramid, kevlar, carbon, and glass fibre-reinforced composites, and the transportation sector has instigated the use of these materials in many applications like car interiors and exteriors, dash boards, bumpers, spoilers, seat covers, and mirror casings. NFRC with nanofillers is gaining more attention in the field of engineering, particularly for automotive, defense, building, and construction applications due to better aspect ratio, larger surface area, and attractive properties. The mechanical, tribological, and thermal properties of plant fibre-reinforced composites can be improved through the incorporation of organic or inorganic nanofillers. The present review profoundly explores the effects of various factors influencing NFRC with nanofillers. This paper also summarises the effects of various chemical reagents, fabrication techniques, and industrial applications of NFRC.

An Ergonomics Study and Rapid Upper Limb Assessments (RULA) for a Car Interior to Support Limb Disabled Drivers

The demanding market shows that the need for the disabled vehicles have been increasing over the recent years. However, these factory setting cars are pricey, and its buy-sell process is time-consuming. These cars also are not meant as a universal design or inclusion design type of car, so that when it is designed for the disabled, it can be beneficial for all. With the motivation to include limbs disabled drivers in designing a universally designed car, this study aims to determine the preferred ergonomics interior of the car which can improve features needed to meet the mobility of impaired individuals in most scenarios. 5 simulations were carried out to simulate these conditions using the RULA analysis, in order to simulate the ergonomics impact on the manikin. In the final analysis, the simulations showed a virtuous score, which was between 1 and 2 for the newly redesigned interior, compared to the score of 3 to 6 for current cars. Another verification made, post questionnaire delineates positive responses upon the redesigned parts scoring 70%~90% level of ergonomics rated. Therefore, this research has set forth the necessity of redesigning a car interior and improved its ergonomic features extensively, specifically for lower limb and combined limb disabled drivers.

Influence of Surface Discontinuity on Sound Absorption Coefficient of Vehicle Interior Material

There has been considerable effort in the automotive industry to reduce and control the noise in the car cabin. Selecting or designing a better absorber will enhance the comfort of the passengers in the car. There are many techniques to reduce or control the noise in the car cabin. One of the techniques is to place specific material in order to reduce its acoustical noise. This paper presents a study on sound absorption of the felt, polyurethane foam and fabric which are commonly used as car interior material. Furthermore, the influence of surface discontinuity created between two joined material parts is also investigated. The sound absorption coefficient is measured using two-microphone impedance tube. This tube is used to provide noise source frequency ranging from 50 Hz to 10 kHz. Using the dBAlpha software that is connected to the microphone via Symphonie Analyzer, the sound absorption coefficient of the material for every frequency is presented in tabular as well as in graphical form. The test results show that material selection is significantly important for the absorption of noise. Besides, it is found that the surface discontinuity gives different effect depending on the material. For the felt material, the surface discontinuity has insignificant effect. However, the surface discontinuity may give a moderate effect for other materials such as polyurethane foam and fabric.

Transparent polyurethane coating with synergistically enhanced antibacterial mechanism composed of low surface free energy and biocide

Recently, antibacterial coatings have gained great attention after the outbreak of COVID-19, thus durable transparent polyurethane (PU) coatings with anti-bacterial and anti-fingerprint performances are highly desired. In this work, the low surface free energy enables the hydroxyl-terminated polysiloxanes modified with quaternary ammonium salts (PQMS) enriched on the surface. The optimal PU-PQMS-40 % coating with the thickness of 15 μm displayed 96 % light transmittance and can be adopted to diverse substrates. This resultant coating exhibits excellent antibacterial activity against Gram-negative E. coli (99.2 %) and Gram-positive S. aureus (98.6 %) because of the synergistically enhanced antibacterial mechanism of both low surface free energy (27.54 ± 0.75 mJ·m−2) and quaternary ammonium salts (QAs). It is noteworthy that this antibacterial PU coating is capable of retaining its properties even after being subjected to 210 cycles of abrasion tests, manifesting a superior self-renewability. This coating system with combined features of transparency, antibacterial performance, chemical resistance, and durability make it a promising candidate for applications in the fields of electronic devices, automobile interiors, intelligent glass, and marine antifouling.

Sistem Informasi Jasa Cuci Interior Rumah dan Mobil Menggunakan Metode User Acceptance Test

At this time, the development of science and technological progress is increasing and sophisticated, especially the use of computers and mobile phones that almost use them and have a significant impact. The usefulness of information technology becomes a management of information that is easier to use. The same is felt by the owner of Wowo Clean Solution, wanting to feel an easier dissemination of information but still experiencing a shortage of information and ordering systems that have not been computerized, resulting in the people of Purwokerto not knowing much about home and car interior cleaning services, thereby reducing orders for cleaning the interior of the house and car. Therefore, researchers build a system using the Waterfall Method or the waterfall method is a model developed for software development. The Waterfall method was chosen because this method can help the author to develop the first stage software system that will be built according to the needs of the user (user). This researcher builds a website using the PHP and MYSQL programming languages. The final result of this research is to analyze the response of using the wowo clean solution website. The response to the use of the webiste from the community uses the User Acceptance Test (UAT) model testing. UAT aims to determine the functionality of software testing. The final result of this research is to produce an information system, namely the wowo clean solution website and the results of the examiner's assessment using the user acceptance test with an average score of 80% so that it gets good criteria.

A review of train passenger safety—Inspiration from passive safety passenger protection technology of automobile

Abstract A train collision accident will cause many casualties, so the passive safety protection of the train occupants is very important. The purpose of this article is to obtain recommendations on the research directions of train passenger safety by comparing the passive safety protection of passengers in the fields of automobiles and trains. First, we analyse the collision standards and regulations of automobiles and trains and summarize the content related to the passive safety protection of occupants. Then, based on an extensive literature review, the development status of passive safety protection for automobiles and trains is analysed from three aspects: interior, human characteristics and passenger posture. Finally, some conclusions and recommendations on passive safety protection of train passengers are put forward. The protection method provided by automobile interiors is mainly restraints, while in trains it is mainly separation. For human characteristics, in addition to male and female, the elderly, obese and children are also studied in the automobile. As for posture, the automobile mainly focuses on the posture in reality and future automated vehicles, while in train, there is more research on lateral passengers and standing passengers. Although the protection of automobiles and trains is different, for the passive safety protection of train passengers, the design of automobile interiors can be used for reference to reduce passenger injuries. In addition, human characteristics and posture have a great impact on passenger injury, which should be considered in the passive safety protection of trains.

Electroforming Technology as a Mold for Automobile Interiors

Electroforming Technology as a Mold for Automobile Interiors

A Theoretical Model for Investigating the Structural Dynamics of a Rolling Tyre

Abstract The noise generated by the rolling tyre contributes significantly to the car's interior noise. This is caused by the tyre-road contact, and at low frequencies (0–500 Hz) is mostly transmitted inside the cockpit through the structure-borne transmission path. In support of the studies in this research field, an interpretative model of the tyre-wheel system accounting for the effects induced by the angular speed represents a useful tool. To this aim, we implemented an analytical model based on a flexible ring on an elastic foundation to analyze the dynamics of the tyre-wheel system, in both static and rotating configurations. We fine-tuned the parameters of the tyre based on data coming from experimental modal analysis of the static tyre. Particular attention has been paid to the system's free and forced responses, commonly analyzed with the so-called cleat test. The results are discussed interpreting the behavior in different reference systems.

Evaluating the sustainability of car mat manufacturing

In recent years, the automotive industry has become increasingly concerned about environmental sustainability. Scant information is available on the environmental impacts of car parts. Therefore, this paper aims to assess the life cycle environmental impacts of one of the most important car interior accessories - rubber car mats - and to identify potential improvements. Sensitivity analysis was performed on alternative raw materials and energy sources used in the production of the rubber mat, as well as different raw material supply transport distances. Rubber and carpet mats for a car have also been compared in terms of environmental sustainability. The inventory is primarily based on primary data, and the evaluation considers a broad variety of environmental impact categories to both human and ecosystem health. The results reveal that the global warming potential of a set of rubber car mats is estimated at 5.9 kg CO2-eq. The car mat manufacturing is the main contributor to the majority of impact categories (47%–83%) due to the high energy consumption caused by the long mixing time and hot-pressing process. The only exception to this is the depletion of abiotic resources and the ozone layer, which are primarily caused by the production process. The impacts are highly sensitive to the electricity source and types of rubber. The use of carpet mats instead of rubber mats in motor vehicles increased environmental impacts (26%–92% higher) in all categories. The findings of this study will help the automotive industry benchmark the industry and maximize its environmental sustainability. Consumers will be interested in the findings as well, as they will help them identify environmentally more sustainable car parts.

Bending waves focusing in arbitrary shaped plate-like structures: Study of temperature effects, development of a digital twin and of an associated neural-network based compensation procedure

Advanced automotive audio applications are more and more demanding with respect to the visual impact of loudspeakers while still requiring more and more channels for high quality spatial audio rendering. Removing classical heavy and large electrodynamic loudspeakers and using car interior plate-like structures driven by state of the art spatial sound algorithms appear as a promising solution to tackle both issues. However, to meet spatial audio rendering constraints, the bending waves generated within car interior plate-like structures must be focused at a given position and to a certain extent within the host structure. Theoretically, this means being able to invert in a robust manner the spatio-temporal wave propagation operator for the generated bending waves to fit a given target shape. The propagation operator inversion method considered here is the spatio-temporal inverse filtering (STIF) method based on the knowledge of the propagation operator on a regular spatial grid over the structure at a given temperature. However, in a car interior a high temperature variations exist and can adversely impact the performances of the STIF method, mainly because dynamical properties of the host structure (built up with polypropylene in most cases) largely vary within this temperature range. Even if the STIF method has already been adapted and assessed in the context of automotive audio reproduction, no study dealing with the effects of temperature on the STIF method and providing potential mitigation procedures avoiding experimental measurements at each temperature has been reported. To address that issue, the influence of temperature on the behavior of a polypropylene plate is first experimentally quantified. A model updating method is used to build a finite-element model of the plate taking into account temperature effects. This digital twin of the host-structure is then used to assess the influence of the temperature on the STIF method. A neural network based controller is finally trained and validated on the digital twin in order to compensate for the effects of temperature on STIF filters. Obtained results demonstrate that this procedure successfully allows to compensate for temperature effects on the STIF method applied to polypropylene plate with very limited experimental needs, thus paving the way through an industrial development of such approaches.

Determination of the chemical composition of waste dust from process operations – case study

The main environmental wastes generated by the automotive industry include lubricants and coolants for cars; water and solvent cleaning systems; paint; scrap metal and plastics. It is important to establish the source of the waste release to establish appropriate organizational measures to ensure the correct environmental approach and safety issues. In the present work, several tests have been carried out to identify the source of release for a specific dust waste that appears in the process of car's interior finishing. XRF, ICP-OES, and FTIR analyses were performed for this purpose.

Investigation on mechanical, microstructural and thermal properties of coconut peduncle fibre epoxy resin

Now days the natural composite materials are used in various applications like automobile interior decorations, Air craft applications, Industrial duct production etc… The Coconut peduncle leaf stack fiber (CPLSF) and Multi-Walled Carbon Nano Tubes (MWCNT) are different percentage used such as 0 %, 1 %, 1.5 % and 2 % are used to treat the extracted fiber to explore the influence of MWCNT over the properties of fiber. This research work is focused towards determining the static and dynamic mechanical properties and morphological analysis. This coconut peduncle leaf stalk fiber treated with the distilled water and alkaline sodium hydroxide. The length of each specimen’s fiber is slized into 3 mm, 7 mm and 10 mm. The flexural, impact and tensile test are conducted to reveal the mechanical properties of the component. Then the further investigation on thermogravimetric analysis (TGA) to confirm the thermal stable to confirm and finalize the presence of impurities over the surface of raw fiber.