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Side Door Closing Sound Quality is one of the first impressions a potential customer has about a vehicle. It can enhance an impression of robust and high quality vehicle. This paper is a study of Side Door Closing Sound of a specific vehicle model. The main objective is to understand how Door Closing Sound Quality varies over several vehicles samples and how to improve the design and/or production process in order to achieve better Sound Quality. Two vehicles (same model) with distinct performance have been chosen among several samples. Both have been evaluated and the physical differences are weighted to realize what really matter for Door Closing Sound Quality.

Among all types of vehicle crashes, rollover is the most complex and yet least understood. During the last decades, a constant increase in the studies involving rollover crashes and injuries associated with it can be observed. Although the rollover is not the most frequent type of accident, it is of the greatest significance with respect to injury and trauma caused to the vehicle occupants. The existing standards and procedures to test rollover crashworthiness are still not suitable to computer simulation because of the huge computational effort required, and the need of faithful/overly complex representation of the aspects involved in real crashes. The objective of the present work is the development of computational models particularly adapted to simulate different standards and procedures used to evaluate the vehicles' roof strength. The models are compared with other approaches, and their advantages/disadvantages are discussed.

Even though the rollover is not the most frequent type of accident, it is of the greatest significance with respect to injury and trauma caused to the vehicle occupants. The need to reduce death incidence and serious injuries has increased the importance of computational simulations and prototype testing. This study presents finite element model to simulate rollover events and to predict possible injuries caused in the head, neck, thorax and cervical spine. Numerical models of a sport utility vehicle (SUV) are simulated including anthropomorphic dummy to represent the driver. The injury risks and traumas are verified to the driver considering belted and unbelted dummies. The computational methodology developed proved to be efficient for the evaluation of the vehicle's roof structure in rollover events.

Test Protocols for pedestrian head protection in a car pedestrian accident have been discussed for several Technical Communities in order to identify ideal boundary test conditions to evaluate injury limits. With the purpose to harmonize with final Global Technical Regulation 9 for Pedestrian Protection published by ECE in January 2009, European New Car Assessment Program (ENCAP) has changed their Child and Adult headform weight and geometry boundary test conditions. However 5 Kph remains as difference between both protocols. This work presents a comparative head impact test analysis for both headform at ENCAP and GTR#9 boundary test conditions when performed at critical bonnet regions.

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.

The purpose of the theme developed in this work is to increase the volume of information related to vehicle evaluation and how human perception can be translated into numbers, thus facilitating the process of definitions, refinement and analysis of its performance. Based on the discipline of psychophysics, where it is possible to study the relationship between stimulus and sensation and the use of post processing tool known as PSD (Power Spectral Density), post process the acceleration data of inputs perceived by the occupants of the vehicle, when driving in routes considered ergodic. By this, in a summarized way, get to human subjective perception of comfort. This material shows in a conceptual way a sequence of studies that were conducted to make it possible, to generate a performance classification of the subjective vehicle attribute of Smoothness, by processing values of acceleration measured the driver's seat.

In the current automotive industry, in an increasingly challenging environment due to strong competition, to develop a product that performs its functions objectively, with quality and mainly with the lowest possible cost, these are the keys to conquer competitive advantage. This paper is intended to explore cost reduction of an automotive system by using the techniques of the methodology EV / AV (Engineering Value / Analysis Value). The analysis are framed as exploratory, in the form of study, with ratings of the components and their functions, followed by the generation of ideas with the completion of an indication of a great potential for a product development with optimized cost.

This work conducted an optimization in sheet metal blank's sizes for cold pressing automotive parts, comparing dimensional characteristics of automotive hood outer panels deep drawn with commonly used blank sizes for this process. As a result, it was possible to suggest modifications to smaller blank sizes, accordingly to the improvement accomplished in this work. The experimental study was conducted from observations in part's superficial aspects after its deep drawing process, which was realized in a commonly used tooling for automotive industry, with a blank's width reduction for the suggested case. The results showed a cost reduction opportunity based in this optimization.

This Paper presents the “Frequency Sweep Virtual Analysis” as a tool to help to define the best powertrain mount concept in order to identify the resonance mode frequency on Powertrain System. Applying this method, we can identify proposals to reduce loads in the Powertrain system due the resonance mode and consequently minimize possibility of exceeding material strength. The “Frequency Sweep Virtual Analysis” drives the powertrain mounts design to avoid running many Road Load Data Acquisitions (RLDA) in a trial-and-error process (Cost reduction and timing savings).

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.

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.

Brazil, that presents one of the highest accidents indexes of the world, does not have any specific regulation related to the use of an external light during the day time which provides a better visibility of the vehicle in movement and according to studies gives more reaction time for the other road users. Many countries in Europe and North America shows good results since they adopted the lights on during the day with collision reduction of vehicle to vehicle, vehicle to pedestrian and vehicle to cyclists. The aim of this study is to show the benefits of the Daytime Running Lights (DRL) and its relation to the reduction of the traffic accidents, as well as a brief analysis on the use of a dedicated system, which can be more efficient since it can be designed to provide a light distribution allowing a better visibility as possible.

On Current Automotive Application, including Brazil, there are significant initiatives to reduce fuel consumption and emissions, like INOVAR Auto and others worldwide. There are several initiatives for Hybrid vehicles, electrical vehicles and other fuel cell energy vehicles, besides the additional energy supply in order to reduce the fuel energy consumption and consequently the emissions. The vehicle features represents a huge part of energy consumption, because the generator needs to feed all of those features. To reduce this energy required from generator and consequently from vehicle accessory drive and engine itself, we are aiming to reuse one of the bigger energy wasted on vehicle combustion engine, the thermal one. For that end, the Thermal Energy Generator is applied on major heat sources and convert the thermal energy through electrical energy due to “See-beck effect cells”.

This paper explores the method of modeling and validation the computational tools able to accurately replicate the dynamic behavior of a Formula SAE vehicle. Based on limitations in conducting physical tests, it is possible to mathematically predict the forces and momentum generated on the steering column of the vehicle, minimizing effort and improving driver comfort even before the component physically manufactured. The results in permanent state due technical instrumentations were used in the physical vehicles and compared with other proposals (skid Pad test). As the software simulating the same path, it was possible to adopt values of speed and wheel steering, allowing compare the dynamics of the vehicle, through the signals from other sensors installed in the data acquisition system, validating the behavior of the models presented in permanent state. Other aspects were studied to understand vehicle behavior concerning lateral stability and steering behavior.

Using current technologies, a single “entry level” vehicle has millions of electrical signals sent through dozens of modules, sensors and actuators, and those signals can be sent over the air, creating a telemetry data that can be used for several ends. One electrical device is set up to have diagnosis, in order to make maintenance feasible and support repair, plus giving improvement directions for specialists on new developments and specifications, but in several cases the diagnosis can only determine the mechanism of failure, but not the event that triggered that failure. Current evaluation method involves teardown, testing and knowledge from the involved specialized team, but this implies in recovering of failed parts, which in larger automakers with thousands of dealers/repair shops, reduces the sample for analyses when there is a systemic issue with one component.

Door Closing Effort is one of the first impressions a potential customer has about a vehicle. The energy someone needs to give out to push and lock a side door vehicle is easily felt and can enhance the impression of a robust and high quality design vehicle. In other words, Door Closing Effort is one of the issues manufacturers shall look over in order to achieve perfect levels of Human Vehicle Integration (HVI). The aim of this paper is to present a case study of Side Door Closing Effort of a specific Hummer vehicle. It will be shown how door closing effort varies according to several parameters, and how to improve the design and/or production process in view of achieving better effort levels, considering the Hummer case as a background. Several variables that influence on the overall energy of this process have been evaluated, and the physical differences were weighted to demonstrate what really counts for reaching a comfortable level of Door Closing Effort.