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Optimizing the wiper system performance motivates the design engineer to create a product as robust as possible against the occurrence of wipe defects related to vibratory phenomena between the rubber blade and the windshield. In some configurations, these vibrations generate visual or audible annoyance for the driver. These instabilities phenomena only appear under specific operating and environmental conditions characterized by windshield moisture and cleanness, contact pressure of the rubber blade on the glass, attack angle of the wiper blade on the windshield, component stiffness, windshield curvature etc. In the process of eliminating all potential instabilities, modeling the wiper system structures can contribute to understand its working dynamics. Therefore, a new computation tool is developed and validated by experimentation on a specific test bench.

An experimental investigation is first carried out to analyze the influence of the geometrical configuration of a wiper system on the chattering occurrence. The measurement results show a combined influence of the load applied on the rubber blade and the attack angle on the vibratory level of the blade. A mathematical four-degree of freedom model, based on the Sprag-slip theory, is developed to simulate the behavior of the rubber blade during the wiping motion. A dynamic analysis is then performed to define conditions for stable motion of the system. The comparison of these theoretical unstable configurations and the experimental chattering cases shows good correlation. This theoretical survey points out necessary conditions for unstable motion, in terms of orientation of the rubber blade to the glass surface.

The mechanical pressure distribution under a wiper blade is considered as an essential parameter for the generation of wiping defects. In this paper, experiments are first performed to show the heterogeneity of this parameter on a flat glass due to the structure of the wiper blade. This heterogeneity is then strengthened by the curvature of the windshield as observed in following experiments. Thanks to these results and conclusions, a mathematical model, based on elastic foundations theory, is developed here for the simulation of this parameter. The final theoretical results show good correlation with experiments on either flat glass or real windshield. From now, this model provides a numeric tool to engineering departments, for the simulation of the pressure distribution under a wiper blade in the early phases of the design of new system. The algorithm, which requires a general description of the system, can be applied to any wiper blade on any windshield and requires little CPU time.

The forming of alloys from the liquid state can be realized thanks to various casting technologies where the temperature of the metal is high enough to fill a given die correctly. A variety of casting defects often occur in the final part, such as gas porosity, shrinkage porosity and hot cracking. In the case of the magnesium foundry, all handling of molten metal requires serious safety precautions to avoid explosion and burning. Protective gas mixtures (SF6, SO2, CO2) are used to minimize the ignition risks but have a bad impact on the environment. The semi-solid forming operates using a lower temperature in the solidus-liquidus range and seems to be interesting, in particular, for the quality requests of the die caster and for safety and a clean environment. The purpose of this paper is to present the mechanical results of tensile tests carried out on magnesium standard samples, which are cast by Thixomag® process from the semi-solid state.

This paper presents the potential for rear closure submodules. Side door modules and lightweight rear closures have attracted a lot of attention in recent years. However the characteristics of future liftgates allow the design of specific mechatronic sub-modules (e-modulesTM). Beside structure, rear closures satisfy three main functions: rear vision, rear signaling and rear access. All are undergoing a generation change that will be outlined in the first part of this paper, system by system. Each time the rationale behind modular integration, whether electronic or mechanical, will be reviewed. The second part presents examples of e-modulesTM that illustrate the potential gains in terms of ease of assembly, packaging optimization and network integration.

For wiper systems, rubber-wiping elements are one of the key components ensuring excellent wipe quality and, therefore, satisfying driver visibility, security and comfort. In order to track the rubber element wear precisely and to know when the blades have to be changed, a wear indicator for the rubber element has been developed. The indicator is made of a black plastic material with an adhesive, pressure sensitive, backing located on the main bow. With time and external stresses, the sticker turns a green color at mid life, and yellow at the end of life. Yellow color indicates to the driver, the end of the effective life of the wiper blade.