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In recent years, electric vehicle and hybrid vehicle are either on the market or under intensive research and development (R&D). Since the concept of auxiliary power unit (APU) was brought into the automotive industry, the range-extended electric vehicle (ReEV) has become the favor of the worldwide manufacturers. Normally, the APU starts and stops more frequently in response to the control strategy compared with traditional vehicles, which will affect the ride comfort of passengers. Thus, APU start-stop NVH refinement is an important aspect of ReEV R&D. In this paper, a subjective evaluation on a ReEV was performed to quickly diagnose NVH issues firstly. Based on subjective results, the NVH experiment in a semi-anechoic room was carried out to troubleshoot these issues. The accelerations of the APU mounts, the seat track and the steering wheel as well as interior noise level were acquired and analyzed.

The torque sensing module is an important part of EPS (Electronic Power Steering) system. There are various solutions in the market based on different technologies i.e. Potential meter, Inductive and Hall sensing. As a trend, more and more EPS system integrators adopt Hall-based torque sensing solution, most of which consist of a magnetic ring, a magnetic flux detector to read the magnetic flux from the magnetic ring and a flux conductor/concentrator to lead the magnetic signal to a Hall device to convert magnetic flux level to electronic signal. However, available solutions require high mechanical precision from the magnetic flux detector and conductor/concentrator. Also, the magnetic ring in the existing solution is magnetized after its preformation which causes a lower signal-to-noise ratio at the input of the entire system due to the process and brings about less accuracy of the torque sensing module.

Performance abilities that exceed the physical capability of current safety features and design compromises can be achieved in the future by adding new active safety devices externally to autonomous vehicles (autonomous car safety efforts centered on improving problem detection and reaction times are beyond the scope of this paper). This paper shows that multiple physical improvements are now available to car designers including increased braking friction/capability on dry roads, the ability to dry/clear-out wet surfaces, active anti-rollover protection, active anti-over-steer, spin prevention, and automated jacking/lift capability.

The need for a voice recognition system in the automotive industry is growing day by day. In our current voice recognition system, Hyundai's ‘Blue-Link’ and KIA's ‘UVO’ are developed with Microsoft which is a global software company. The system launched domestic market recently. Since usage of voice recognition system are increasing, research and development of Voice Recognition system also increase very fast. Research is mostly focus on increase recognition rate of speech. However there is no research of interior layout considering voice recognition usability. So in this research, we discover interior design factors for maximizing voice recognition usability.

In the view point of driving safety, the crosswind sensitivity of a vehicle becomes more important, as the driving speed in highway gets higher in these days. The sensitivity of a vehicle to crosswind depends on many factors, including the design of the suspension and aerodynamics of the body, etc. However, the knowledge about this phenomenon has still to be improved, in order to develop vehicle with optimum characteristics for crosswind stability. In this research, the physics behind the sensitivity of a vehicle is discussed in detail through various kinds of virtual test using computer aided engineering (CAE) simulation scheme. In the first, a reliable simulation model for vehicle, driver, wind generator and interactions among them is built. This simulation model is verified by comparison with test results of real vehicle. Then, the sensitivity analysis is carried out to find out the most influential design parameters.

For the robust passenger NCAP(New Car Assessment Program) 5star and the stable neck injury performance, a new concept of passenger airbag has been required. Especially, the deployment stability and the vent hole control technology of the passenger airbag can be improved. According to these requirements, the deployment stability technique has been studied and the ‘Active Vent’ technology has been developed. As a result, these technologies have led to achieve the robust NCAP rating and are applied to the production vehicles.

It has become an important trend to implement safety-related requirements in the road vehicles. Recent studies have shown that accidents, which occurred when drivers are not focused due to fatigue or distractions, can be predicted in advance when using safety features. Advanced Driver Assistance Systems (ADAS) are used to prevent this kind of situation. Currently, many major tiers are using a DSP chip for ADAS applications. This paper suggests the migration from a DSP configuration to a Microcontroller configuration for ADAS application, for example, using a 32bit Multi-core Microcontroller. In this paper, the following topics will be discussed. Firstly, this paper proposes and describes the system block diagram for ADAS configuration followed by the requirements of the ADAS system. Secondly, the paper discusses the current solutions using a DSP. Thirdly, the paper presents a system that is migrated to a Multi-core microcontroller.

This paper presents a study performed in 10 vehicles available in Brazilian market where the drivability with ethanol and gasoline, also referred as gasohol were compared. The motivation for this work came from the constant competition of the automotive industry, where engineers are searching for ways to improve the quality of the products aiming the “best in class” drivability with the best cost efficiency. For the Brazilian market, a further complexity is added to the development and verification process, which is the need to design and verify the controls and calibration considering the two fuels available in the market, the ethanol and the gasoline. In order to determine how the drivability is impacted by the ethanol, the paper presents a study where the drivability data were generated using the objective drivability measurement system AVL-DRIVE™.

Many countries are introducing fuel economy regulations in order to reduce the average emissions of light duty vehicles, since fuel consumption of vehicles is an important factor in air pollution. The lubricant has a significant role in reducing friction losses hence the fuel consumption, but the impact depends on the engine operation regime and the manner in which the lubricant components work together to change frictional properties. Different driving cycles are used by different countries and organizations to measure fuel consumption. The most common driving cycles are the European NEDC and the North American FTP-75 vehicle transient cycles. Fuel economy at full load and BSFC (Brake Specific Fuel consumption) are also common methods of measuring engine fuel economy.

Mechanical components, such as parts of internal combustion engine, subject to cyclic loads can be submitted to quenching process in order to improve mechanical properties preventing fatigue failures in service. It is important that such components, due to quenching process, get a high hardness surface layer, increasing the resistance to fatigue, and a tenacious core, with a high capacity of absorbing impacts. In this paper, a multiphysics simulation method of quenching process using Finite Element Method is presented. The proposed simulation method include two stages: heating and cooling. In the first stage, the mechanical component, initially at ambient temperature, is heated by electromagnetic induction to a temperature above the steel austenitization. In the second one, the component is cooled by liquid immersion.

A hydraulic accumulator used in gear selection phase of an automated manual transmission was studied to employ simulations which could predict response time of entire system. A spring-mass-damper mathematical model was created from real data and response time measured in acquisitions of a first prototype system built. The model objective was to determine values for damper coefficient and spring mass rate to be used in the design of a pair of springs with enough stiffness to achieve system response time desired. With prototype data and mathematical model developed, predictions about response time of a final system were performed and a spring rate value was determined to satisfy with response time requested. From model data, numerical structural analyses were performed in order to predict eventual final system failures due to the stiffness values involved.

Powertrain performance analysis is applied by the automotive industry to verify the dynamic performance of the vehicles, which is an outcome of the combination of the engine, the gear box, the driveline, the carrier ratio and the tire size. On this analysis, the main non powertrain factors are the total combined vehicle weight and the route topography. The total combined vehicle weight is a known factor. It is related to the vehicle application and it is restricted to pre-established limits. In general, the route topography is the unlikely factor, due to the huge coverage of the potential paths. Traditionally, the route topography determination is carry out supported by global positioning system (GPS) devices. Appling this methodology, the full route must be tracked by a vehicle equipped with GPS. Its complexity, time and cost increase in case of multiple routes must be tracked, in places geographically remote each other, as different regions, provinces, states or countries.

The hybrid electric vehicle (HEVs) is an alternative to reduce the high dependence on petroleum products, because maintains the characteristics attributed to conventional vehicles such as performance, safety and trustworthiness and reduced the fuel consumption. Some modifications are necessary in the vehicle longitudinal dynamics equationing, to provide a specific power management control system, because of the electrical power source addition that complements the conventional engine and powertrain system. In this paper is used the HEV parallel configuration, where both drive systems are directly connected to the vehicle wheels, maintaining the engine/powertrain in the front wheels and electric motors directly coupled to the rear vehicle wheels.

The internal combustion engines emit combustion gases which contain nano and micrometric particles that are harmful to human health, causing deleterious damages to the human's respiratory system. In Brazil, heavy vehicles, such as buses and trucks, have diesel engines that work under high loads and run through metropolitan areas or in intense traffic flow roads. They are considered, nowadays, the main solid particles emitter in several World's areas. There are already standard systems to analyze these particles quantitative and qualitatively at high prices collected from vehicle gases emissions in places such as bus stops. This paper presents a new method which retains solid micrometric particulate matter emitted by diesel engine. It is simple and has a relatively low cost. A sheet of textile element was encapsulated in a system for gripping micrometric particles emitted by diesel single-cylinder engine operating in a bench and coupled with a electrical generator.

Bus drivers are daily exposed to whole-body vibrations (WBV) submitted to risks for develop health problems related to these conditions. Numerous studies focused to quantify and identify the risks that drivers are exposed have been developed in recent years. Many factors influence the transmission of vibration to the body. Road type may be an important factor in determining the WBV exposure a bus driver receives. In urban areas, common types of routes include several road surfaces like: smooth highway, older rough freeway, pavement, bumpy, speed humps, and others. The purpose of this study was to determine whether different kinds of road surfaces, found in urban routes, cause different WBV responses, and determine the influence for each road type in daily exposure to WBV according the standard ISO 2631-1 (1997).

The sound of the engine has a significant influence on the driver's perception of the performance, comfort and quality of a vehicle and hence their overall satisfaction with the product. Therefore achieving the right engine sound inside the vehicle is one of the key deliverables in the NVH process. In the case of a vehicle fitted with an internal combustion engine this is usually done by tuning the mechanical components whereas in quiet vehicles (e.g. Hybrid or Electric) a virtual engine sound can be generated using sound synthesis algorithms incorporated into the vehicle's electronic systems. In either case, the task of developing an appropriate engine sound can be made more robust, efficient and understandable by using an NVH Simulator, which is an interactive tool for auralising and evaluating all NVH data (Test and/or CAE) in the correct context (i.e. while driving) at all stages in the development of a vehicle.

This article presents a comparative analysis of the influence of different types of flows over fan noise propagation and scattering within the nacelle intake of aircraft turbofan engines. The methodology for the noise simulation is explained. First, the fan noise source is modeled using a boundary condition that represents all the uncorrelated cut-on modes in the interior of the nacelle duct. Then different types of flows and flight conditions are considered in order to determine the influence of the aerodynamic phenomenon in the noise emitted by the nacelle intake. The liner attenuation is also simulated by mean of Myers boundary condition. Finally the results for far field noise are validated against numerical data obtained from the literature for hard and lined wall conditions.

Microphone array based techniques have a growing range of applications in the vehicle development process. This paper evaluates the use of Spherical Beamforming (SB) to investigate the transmission of wind-generated noise into the passenger cabin, as one of the alternative ways to perform in-vehicle troubleshooting and design optimization. On track measurements at dominant wind noise conditions are taken with the spherical microphone array positioned at the front passenger head location. Experimental diligence and careful processing necessary to enable concise conclusions are briefly described. The application of Spherical Harmonics Angularly Resolved Pressure (SHARP) and the Filter-And-Sum (FAS) algorithms is compared. Data analysis variables, run-to-run repeatability and system capability to identify design modifications are studied.

With the increase in aircraft transportation and, consequently, aircraft noise in the last decades, measurement of acoustic liner impedance under grazing flow has become a point of interest. Different indirect methodologies have been developed by independent research groups to solve this problem. The Mode-Matching technique and, more recently, the Two-Port method are examples of developed methodologies that use acoustic pressure measurements in a test rig where a liner sample is subject to grazing mean flow to educe its impedance. In this paper, both methods are explained, implemented and used to educe the acoustic impedance of different liner samples in a recently developed grazing flow impedance eduction test rig. Additionally, both methods are compared based on their computational cost and limitations.

One of the critical tasks of aircraft design is the definition of mass of aircraft's main items, and the aircraft mass distribution. Depending on the type of aircraft (e.g. commercial, general aviation, highly-maneuverable) different types of mass distribution data or trend curves are available; and in general these curves are based on the existing aircraft. But some lack of data is noticeable in terms of solar aircraft, i.e. the available information in terms of mass trends does not fulfill the needs of the designers of this type of aircraft. Considering this perspective, the main motivation of this study is to provide some information, in terms of mass trends and mass analysis for sun-powered aircraft, which could fill part of the gap, and stimulate other efforts in the same direction. Through this work, studies of mass breakdown of different examples of sun-powered aircraft are presented.