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Through computational dynamic simulations is possible to achieve high reliability index in the development of automotive components, thereby enabling the reduction of cost and time of a product development with considerable gain in quality. This work suggests the validation of a methodology for simulation where is possible to improve the confidence level for design flexible components, such Heater and Cooling hoses that are under dynamic engine action, in relation to the physical model. Known the difficulty in predicting non-linear mathematical relationship deformation under effect of forces and moments, was established a study based on experimental measurements where were used as input parameters to simulate the dynamic behavior of flexible components, in this case, coolant hoses.

In order to illustrate the constant development of the automatic transmission controls area, this paper describes how the garage shift calibration works in vehicles with transverse front wheel drive powertrains. A garage shift (GS) is the turbine speed transient commanded by the shift lever movement from Park to Drive or Reverse, from Neutral to Drive or Reverse, from Drive to Reverse, from Reverse to Drive, or from Drive or Reverse to Neutral [1]. A usual metric to verify the garage shift comfort is the data acquisition of the fore-aft acceleration on the seat track, but also the shift time should be considered, as well as the clutch energy and the repeatability of the shift feeling for different temperatures and engine idle speed levels. This paper demonstrates the transmission calibration strategies to determine a sensitive and a non-sensitive garage shift and its interactions with the engine calibration.

Acoustics, in a broad sense, is an essential product attribute in the automotive industry, therefore, it is relevant to study and compare theoretical and numerical predictions to experimental acoustic measurements, key elements of many acoustic development processes. The numerical methods used in the industry for acoustic predictions are widely used for exhaust system optimization. However, the numerical and theoretical predictions very often differ from experimental results, due to modeling simplifications, temperature variations (which have high influence on speed of sound), manufacturing variations in prototype parts among others. This article aims to demonstrate the relevant steps for acoustics development applied in automotive exhaust systems and present a comparative study between experimental tests and computer simulations results for each process. The exhaust system chosen for this development was intended for a popular car 4-cylinder 1.0-liter engine.

It is known acoustic comfort is a key feature to meet customer expectations for many products. In the current automotive industry, vehicle interior quietness is seen as one of the most important product attributes regarding perceived quality. A quiet interior can be achieved through an appropriate balance of noise sources levels and acoustic materials. However, the choice of the most efficient acoustic content may be challenging under severe cost and mass restraints commonly found in emerging market vehicles. Therefore, it is fundamental to develop efficient materials which will provide high acoustic performance with lower weight and cost. In this paper the fine tuning of the headliner structure is presented as an efficient way to increase acoustic performance. Structures currently employed for this vehicle subsystem are described. Airflow resistance and sound absorption measurements are used to guide development and make precise manufacturing process changes.

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.

Vehicular manual transmissions systems often use a vent or breather to allow pressure control inside the main structure. This pressure variation comes along with differences caused by working temperature range. However along with air flow these vents may occasionally allow oil passage noticed by vehicle owner as a transmission leakage event. The more sophisticated the more expensive is the venting device which may contain membranes, labyrinths, baffles and other solutions to avoid leakage. The purpose of this paper is to present a simplified solution to avoid transmission fluid leakage by combining a regular sealing device (fiber concept gasket) and a baffle to avoid oil splash to reach the venting device. The proposed concept took into consideration a quick implementation aspect, low financial impact and less complexity to the overall current system modifying an existing component by adding secondary function instead of creating additional components.

Product Design is a process of creating new product by an organization or business entity for its customer. Being part of a stage in a product life cycle, it is very important that the highest level of effort is being put in the stage. The Design for Six Sigma (DFSS) methodology consists of a collection of tools, needs-gathering, engineering, statistical methods, and best practices that find use in product development. DFSS has the objective of determining the needs of customers and the business, and driving those needs into the product solution so created. In this paper the DFSS methodology is employed to develop the optimal solution to enhance sound transmission loss in a vehicle front of dash pass-through. An integrated approach using acoustic holography and beamforming Noise Source Identification (NSI) techniques is presented as a manner to improve sound insulation during vehicle development.

The control of noise and vibrations using conventional damping materials is typically associated to mass penalties in a vehicle. A lightweight alternative employs piezoceramic materials connected in series to a resistor and an inductor (R-L circuit) to perform as mechanical vibration absorber, called piezoelectric resonator. In this paper, piezoelectric resonators are designed to attenuate vibration in a vehicle panel. The choice of design parameters, such as correct placement for the piezoelectric patches and the optimal electrical circuit values, is assisted by Finite Element simulation (FE) and theoretical analysis. Measurements of Sound Transmission Loss (STL) and modal analyses are conducted to demonstrate the efficiency of the proposed technique when compared to a conventional damping material.

The purpose of this study is to establish the criteria of election of an electrical architecture tailor-made for the emerging markets, to be applied during the whole vehicle's lifecycle. A literature review about related subjects as the meaning of "electrical architecture," its techniques, criteria and methodologies of development, and the definitions of emerging and developed markets is also presented. Based on the bibliographical research, documentary analysis and unstructured interviews with active members of the automotive industry, the criteria for election of electrical architectures for emerging markets was established, as well as their describers and swing-weights, required by the use of the additive aggregation method - a multi-criteria decision taking method. The criteria were applied in two case studies of automotive industry: the developments of a low-cost hatch vehicle and a mid-size luxury sedan vehicle, both designed for emerging markets.

Noise generated during tire/road interaction has significant impact on the acoustic comfort of a vehicle. One of the most common approaches to attenuate road noise levels consists on the addition of mass treatments to the vehicle panels. However, the acoustic performance of sealing elements is also relevant and has an important contribution to the noise transmission into the vehicle interior. In this paper the correct balance between the mass added to treat vehicle panels and sealing content is investigated. The procedure to quantify the critical road noise transmission paths consists of recording interior noise levels as applied treatment is removed from potential weak areas, such as wheelhouses, floor, doors and body pillars. It is observed that the noise propagation through body pillars has a direct influence on road noise levels.

Nowadays, electromagnetic compatibility (EMC) has taken an important role in automotive development. This is because the effects that EMC can cause in a vehicle or on the environment. All systems contained in a vehicle emit EMC, and can be influenced by it also. During the vehicle design phase some variables have to be considered and improved to make the vehicle to be electromagnetic compatible. We can list the vehicle systems as electromagnetic generators or victims, as below: Generators: Ignition GPS transmission system Mobile phone transmission system Electrical motors Radars Power modules Victims: Sensors Cables Control modules (BCM, ECM, etc.) An example of a complete system subject to the EM effects is the X-by-wire (or drive-by-wire) system, where mechanical systems are substituted by modules, cables, sensors, actuators. This system has to be designed considering electromagnetic compatibility.

The present work gives an overview of the current situation of failures that may occur in automotive components, showing their distribution in the vehicle and the causes that make them occur, trying to emphasize the different materials which are used in the manufacturing of these components. This work is a technical approach strictly supported by an engineering concept which aims to discuss the different factors which contribute to cause premature failures of automotive components, prior to their utilization in the field or when they are exposed to the most variable conditions of use. One of the most important objectives of this study is to call the attention of design engineers, research engineers and manufacturing people to the importance of the components integrity which shall be taken into primary consideration in the design phase as well as in the specification of the material and process of manufacturing.