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Current vehicle concepts necessitate the multiple measurement of several variables required by separate electronic systems in the motor vehicle. There is the need to make sensors bus capable by the incorporation of electronic components in new definition concepts, in other words to make them multiply usable. Such bus concepts are at the present time taking concrete shape. The step of introducing electronics - especially digital - to the measuring point may simultaneously be used to considerably improve utilization of the information content of sensor structures using means of indivdual, digital correction to a greater level than has until now been technically possible. There remains the demand for high stability and reproducibility of the sensor properties over time. These signal preprocessing and information condensation processes on the spot also satisfy the need to relieve the central control units.

The new aerial communication protocol “Controller Area Network” (CAN) efficiently supports distributed realtime control in automotive applications. In order to unload CPUs from high-speed message transfer, dedicated CAN hardware handles messages up to the communication object level. In multiplex wiring message rates are one to two orders of magnitude lower, allowing to implement the upper communication level more cost-effectively in software. This reduces CAN interface hardware to bitwise protocol handling only. It may be incorporated even into low-end microcontrollers without significantly increasing chip size. Thus the same CAN protocol supports the entire range of serial automotive communication, matching implementation costs to requirements at each performance level.

In order to achieve the best automotive vehicles, companies seek for innovation and new technologies to improve their vehicles. Lately the embedded electronic has been used to add intelligence to a purely mechanical systems. The reduction of fuel consumption, one of the biggest concerns of automotive engineering, for the last couple of years, depends on many factors. Some those factors are engine type, fuel quality, vehicle load, gearshift pattern, vehicle usage, driver behavior and the cooling system technology. The fan applied in cooling system uses part of engine power to run, influencing the fuel consumption and contributing to the global noise level of vehicle, being directly associated with passenger’s comfortable. One alternative in study is the use of a set of electric fans that can be triggered independently, in order to increase the heat exchange in specific places of radiator, while reducing the noise and run time.

Plastic composites are increasingly applied to automotive mechanical parts which demand high strength and high stiffness to meet cost saving and weight reduction. However, plastic component design and molding have often involved a process of trial and error. Recent progress in numerical analysis, including the use of the FEM (Finite Element Method), has made it possible to obtain quantitative data on part deformation and in-mold material flow and to optimize mold geometries. This paper first describes a developemental process of an injection molded accelerator pedal made from glass fiber reinforced thermoplastics (Polyamide: PA, Polypropylene: PP). This process consists of an integrated CAE (Computer Aided Engineering) system which can be applied both to component and mold optimized design. (Fig.1 shows) This paper also discusses the effects of ribbed structure (Type I ∼ III) and the number of molding gates on parts.

This paper studies the feasibility of improving vehicle ride comfort and vehicle dynamics by applying mechanically controlled hydropneumatic suspension to a medium-duty truck. Both front and rear suspensions consist of hydraulic cylinders, small gas accumulators and leaf springs. Hydraulic pressure In the cylinder is controlled by a hydraulic pressure difference between diagonally located hydraulic cylinders. Vehicle test results show that this suspension system reduces vertical vibration in the frequency range of 3 to 10 Hz, the pitch motion during braking, and the roll angle during a steady turn, when compared those the conventional suspension system. However, due to a response lag in the hydraulic control system, this system causes an unfavorable vehicle motion when there is a rapid steering operation, such as an abrupt lane change.

Ride quality is an important purchasing consideration for consumers. It is typically defined in terms of noise, vibration and harshness. These phenomena are a result of vibrations caused at the engine/powertrain and from the road surface, which are transmitted to the passenger cabin. To minimize such vibrations, rubber parts are used extensively at mounting points for the cabin, such as engine mountings and suspension bushings. The vehicle development process increasingly requires performance testing, including rubber parts using CAE, prior to prototype evaluation. This in turn requires a rubber material model that can accurately describe dynamic characteristics of rubber components, particularly frequency and amplitude dependency.

Ambient temperature is a very sensitive use condition for electric vehicles (EVs), so it is imperative to ensure the maintenance of suitable temperature. This is particularly important in regions characterized by prolonged exposure to unfavorable temperature conditions. In such cases, it becomes necessary to implement insulation measures within parking facilities and allocate energy resources to sustain a desired temperature level. Solar energy is a renewable and environmentally friendly source of energy that is widely available. However, the effectiveness of utilizing solar energy is influenced by various factors, such as the time of day and weather conditions. The use of phase change material (PCM) in a latent heat energy storage (LHES) system has gained significant attention in this field. In contrast to single-phase energy storage materials, PCM offer a more effective heat storage capacity.

The vibration damping composite steel sheet was improved in properties such as dependence on temperature, bending rigidity, press formability and spot weldability and compared with damping materials currently used by reviewing composition and adhesion strength of the resin and the mechanical property of the steel skin sheets. By applying the above-mentioned materials to the floor and wheel-house panels, a reduction in noise and vibration was obtained in the application test, and improvement in door shutting noise was also revealed when applying these materials to the door panels.

The use of automatic transmissions currently is associated with softness and comfort while driving, and almost never during races. Despite the many benefits that its application can provide, there is still in the auto racing field a fear of the implementation of this system. Many sport steering fans prefer the manual, sequential or semi-automatic transmissions, because of the fact that in automotive competitions, it is the driver who sets the best time to change the gear. However, the use of Continuously Variable Transmission (CVT) does not only keep the engine always at its best power range, but also eliminates waste of time between gear changes, which can theoretically ensure more uniform and efficient acceleration. In this work, we studied the application of a continuously variable transmission in the Formula CEFAST team's prototype at the Federal Center of Technological Education of Minas Gerais (CEFET-MG) in Belo Horizonte.

The current study is a trial to validate the possibility of using high strength stainless steels, for automotive structural parts. The studied material is a nitrogen-alloyed, high manganese austenitic stainless steel, 204M. The material behavior was compared to that of the conventional metastable austenitic stainless steel 301L. This study shows that the mechanical properties and the formability are very similar for these two steels. A feasibility study for the production of an engine cradel for a medium size passenger car with both stamping and hydroforming was conducted. Lower part weight can be achieved by using thinner gauges than for the conventional carbon steel part. The stainless steel part also showed the potential for higher collapse resistance. These features reveal that high strength stainless steel with high ductility has great potential for use in automotive structural design.

A flexible rebound-type acoustic metamaterial with high sound transmission loss (STL) at low frequency is proposed, which is composed of a flexible, light-weight membrane material and a sheet material - Ethylene Vinyl Acetate Copolymer (EVA) with uneven distributed circular holes. STL was analyzed by using both computer aided engineering (CAE) calculations and experimental verifications, which depict good results in the consistency between each other. An obvious sound insulation peak exists in the low frequency band, and the STL peak mechanism is the rebound-effect of the membrane surface, which is proved through finite element analysis (FEA) under single frequency excitation. Then the variation of the STL peak is studied by changing the structure parameters and material parameters of the metamaterial, providing a method to design the metamaterial with high sound insulation in a specified frequency range.

Presently, plastics are widely used for car interior trims; however, with the growing importance of reducing vehicle weight, plastics application to body and chassis parts is ever on the increase. This tendency results from both the development of new plastics which are applicable to structural components, and the new manufacturing processes which have shortened cycle times. We can find many practical uses for plastics in automobile body parts. Plastic bumpers, including RIM fascia, are not only lighter, they are also less susceptible to damage. This is because they soften the car front and rear ends. Glass fiber reinforced RIM has been applied to exterior panels. Experiments with urethane injections have been conducted in an attempt to improve member strength and stiffness. In addition, composite materials reinforced with carbon or glass fiber have been used, on a trial basis, for such chassis parts as leaf springs, wheels, propeller shafts and engine mounting members.

A new damage model based on the Continuum Damage Model [Ref. 1] has been implemented in MSC Marc. It can simulate three process of damage evolution namely: void generation, growth and coalescence. By deactivating the element when a certain damage value is reached, users can now simulate a whole range of damage process; from micro crack to macro crack growth. Micromechanical models like continuum damage mechanics (CDM) deal damage and failures as characteristics based on material and not as geometry configuration. These models are analyzed and validated only for simple geometrical configurations like uniaxial tensile bar, rotating beam specimen etc. A detailed assessment of the geometry transferability, mesh sensitivity and plasticity effects has been addressed only in a limited number of works.

Automotive OEMs quest for vehicle body light weighting, increase in Fuel efficiency along with significant cut in the emissions pose significant challenges. Apart from the effect on vehicle handling, the reduction of vehicle weight also results in additional general requirements for acoustic measures as it is an important aspect that contributes to the comfort and the sound quality image of the vehicle, thus posing a unique challenge to body designers and NVH experts. Due to these conflicting objectives, accurate identification along with knowledge of the transfer paths of vibrations and noise in the vehicle is needed to facilitate measures for booming noise dampening and vehicle structure vibration amplitude. This paper focuses on the application of a unique design and development of vehicle body structure anti-vibration dynamic damper (DD), unique in its aspect in controlling booming noise generated at a specific RPM range.

This paper focuses on the importance, classification, foundation method of the manikin for design in automobile inner packaging system. Also the positioning in the auto-body system is included. Many kinds of manikins, which are exclusively used in auto-body packaging system, are developed. Lastly, the application of the manikin in auto-body packaging system is discussed. Some examples to demonstrate the application are also given.

The authors discuss the use of Tramasaf, a laboratory instrument that will test the energy absorption capability of automotive components, and will concurrently measure the extent of trauma to the human forehead. The most recently published biomechanics data has required a revision of the original development goals for the device. The paper describes these new goals, the stage of the progress, and some applications which verify the utility of the device.

During the past years, extensive research efforts have led to the development of diesel engines with significantly improved power concentration and fuel efficiency as compared to the past. But unfortunately, the increase of engine thermal efficiency is accompanied by a sharp increase of peak cylinder pressure. At the moment, peak pressures in the range of 230-240 bar have been reported. Naturally, a question remains as to whether such increased peak pressures could have an overall detrimental impact on mechanical efficiency. Initially, it was expected that these would have a negative impact and this was the motive for conducting the present work and developing a detailed friction model. Up to now, various correlations have been proposed that provide the friction mean effective pressure as a function of engine speed and load mainly, neglecting the effect of peak pressure or using data up to 130-140 bar.

During the last fifteen years, Computational Fluid Dynamics (CFD) has become one of the most important tools to both understand and improve the diesel spray development in Internal Combustion Engine (ICE). Most of the approaches and models used pure Eulerian or Lagrangian descriptions to simulate the spray behavior. However, each one of them has both advantages and disadvantages in different regions of the spray, it can be the dense zone or the downstream dilute zone. One of the most promising techniques, which has been in development since ten years ago, is the Eulerian-Lagrangian Spray Atomization (ELSA) model. This is an integrated model for capturing the whole spray evolution, including primary break-up and secondary atomization. In this paper, the ELSA numerical modeling of diesel sprays implementation in Star-CD (2010) is studied, and simulated in comparison with the diesel spray which has been experimentally studied in our institute, CMT-Motores Térmicos.

Modifications to the thickness of the panels in traditional stamped-sheet vehicle body structures can adversely affect the associated noise, vibration, and harshness characteristics. Gauge sensitivity indices characterize the sensitivity of a design's structural performance parameters to such thickness changes, and provide guidance for maximizing the effectiveness of weight reduction efforts. The indices may be applied to an entire body-in-white (global gauge sensitivity), to specific body subsystems (component gauge sensitivity), or to specific critical points in the body continuum (local gauge sensitivity). This paper provides an overview of the theory behind gauge sensitivity methodologies and documents an effort to provide experimental validation of the results.

THE PRESSURE-WAVE-SUPERCHARGER Comprex®, compared to the alternatives of the exhaust-gas-turbocharger and the mechanical blower, is new in the field of passenger car application. The method of how to select the appropriate PWS for an engine and how to match it to the requirements of the engine and vehicle designer is described. Recommendations are made for those components which effect the function and/or efficiency of the supercharger, and therefore, the engine performance. Finally, a brief summary of accummulated experience in this application field is given.