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Quality in the automotive industry means development and manufacturing of vehicles whose specifications meet customer requirements. Among many other quality issues, door closing effort is a vehicle characteristic that strongly affects the customer first opinion about vehicle design. The door closing effort is affected by uncertainties in materials and manufacturing processes. The present paper presents a reliability-based method to evaluate the uncertainties associated with door closing effort due to manufacturing processes. A formulation is proposed to calculate that energy based on three components: energy used to compress air into the vehicle, energy used to compress the sealing and energy used to lock the door. In order to quantify the probability that the door closing effort is greater than a target value, reliability analysis concepts are used based on the uncertainties associated to latch position.

The door is the first system to interact with the customer, allowing the entrance into the vehicle, so it has been given great importance to its performance in all requirements. The automotive door related phenomena studies increased in the past years, once the customer and the market itself have changed their quality standards. The door closing effort is considered a quality issue by the customer, cases it is too high it contributes to quality decrease, based on ergonomics study, each OEM specifies to each vehicle an acceptable value for the closing effort. There is software that uses the finite element method and specific calculation plans for the door closing effort at project phase, but it is necessary lots of data usually not available for the engineer at concept phases. This study's objective is to measure each component contribution in door closing effort with the use of a simplified plan in order to help the product engineer in the door concept phases.

This article will show the relationship between visual quality and engineering technical criteria's, based on the perceptual quality about vehicles style. The meaning of this relation is demonstrated by engineering standards and style parameters. They are referenced to the people reaction to the “new” based on comparison and sensitivity. As the Dimensional Engineering coordinates the engineering standards related to the style parameters, the scope of this article is to show a case that example style characteristics and vehicles project. This relationship is a result of components surfaces and cut lines, classified in gaps, offsets, concave surfaces, convex surfaces, alignment and proportions.

The objective of this article is to show procedure of dimensional problems resolution by correlation of products measurement results the use of a mathematical model for variance analysis demonstrated in a case. The base of this work is in the dimensional problem evaluation in the subdivision of components, potentials of improvement, shunting line X variation, mathematical definition, adjustments of product and the process. The optimization of products and processes is determined by the sequence of activities for problems solution, aligned to the product and process concept development with the possibility to get all the necessary information for continuous improvement. The product and process activities and optimization standards are determined by the chance to solve problems and being actively directed toward the continuous improvement.

All dimensional variation of assembly in structures is based on the geometry stack up between for profiles and localization of pins or holes in fixtures. The capability for a smaller dimensional variation is proportional to the number of stack up and the components geometry of the assemblies. When a product objective is defined, the structure of parts of intermediate sub assemblies compose the basis for the study, therefore the construction and stack up of tolerances of each part or process can be better based on combinations that are defined by the tool of robust engineering. As much bigger is the geometric dependence in the stack up, greater will be the variation probability. One understands for geometric dependence is the detailed dimensional consequences for the geometry of contact between components.

This paper presents a two-parameter Weibull distribution shape and scale parameters calculation method, using sample average and standard deviation. The proposed procedure requires fewer resources for field execution than least squares and maximum likelihood methods, since these methods usually require the use of computers and specific software. Weibull probability paper is easier to apply in the field, but it becomes time-consuming for larger samples.

This paper establishes a methodology for evaluation of the useful life of radial tires used in fleet vehicles, using removed product failure classification and removal time obtained after scrap tire analysis. In the evaluation of the reliability of products, non-parametric and parametric analyses using Weibull distributions are carried out in order to identify and characterize which failures cause higher financial loss in fleets. Comparing the losses due to early failures it's possible to prioritize countermeasures for scrap reduction that present more efficient results.

The purpose of this paper is to analyze the durability behavior of helical gears in manual automotive gearboxes. It shows the evolution of a certain mating gear applied in a specific durability vehicle test where the gears were modified in some design parameters, such as material type, shot-peening, increase of gear width and lead corrections (micro-geometry). This paper intends to evaluate some design parameters and gear life factors that define the mating gear durability and compare the theoretical results against to the practical ones. These gear life factors (application factor, contact factor, material type, etc) are enclosed in known standards (i.e. DIN 3990). The study shows the necessity of testing automotive transmissions in the beginning of design development. This is the best way to identify some failure modes that were not foreseen by the first calculations and hypothesis.

The hazardous bulk chemical liquid cargo transportation is usually made through highways, using special automotive devices, named semitrailer tank, a kind of mobile tank specially developed to perform this task, manufactured with many types of steel, selected according to the chemical characteristics of the product to be transported. Equipment sizing is made based on specific standards which include specified formulas, loading, and safety factors representing the design criteria of this type of device. Despite of the detailed design criteria for semitrailer tank, it has been observed failure of some pieces of equipment during operation, in a shorter effective life than that one considered in the design phase itself. Considering a detailed study of the stress distribution in this type of equipment, this paper shows a verification of the possibility of yielding failure in the semitrailer tank structure.