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The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Currently in automotive industrial, the emphasis on developing a better heat exchanger for vehicle thermal management is not only to address its functional performance but also its durability levels. One of the requirements for the latter is to test the heat exchanger in a simulated stone impact bench test with specified impact energy criteria. Due to various complex influence factors of this test, there is no existing simplified and physical-based relationship for heat exchanger design engineers to apply. With above considerations in mind and based on impact mechanical principles, impact heads configurations and heat exchangers geometrical details, this paper is proposing and developing a simplified impact mechanical models, where physical reasoned influence design factors can be presented and analyzed.

Soot fouling on exhaust gas recirculation coolers (EGRc) decreases thermal efficiency, implying the unfulfillment of NOx standards, and increases the pressure drop producing the malfunctioning of this device. The characterization of soot is of great interest since soot physico-chemical properties may have a direct influence on the degree of malfunctioning of EGRc. Thus, the combined analysis and interpretation of all the soot physico-chemical features are essential to correctly interpret its behavior when soot is deposited on the EGRc walls. In this context, the aim of this study is the characterization of five different types of diesel soot which were collected from several high pressure EGRc, working at different conditions (engine bench and vehicle). Each soot sample was characterized by means of elemental analysis, specific surface area (BET method), FESEM, FTIR, TGA, GC-MS and UV-visible spectroscopy.

This paper proposes and evaluates improvements to a crash simulation of a fuel delivery module in a fuel tank. The simulations were performed in ANSYS/LS-DYNA. Deviations between the original simulation and test data were studied and reasons for the deviations hypothesized. These reasons stemmed from some of the simplifying assumptions of the model. Improvements consisted of incorporating plasticity and strain rate effects into the material models. Performance criteria were also directly incorporated into the material models such that non-performing portions of the model could be deactivated during the simulation. Finally, solid-fluid interactions were added into the simulation to include the momentum transfer from fuel to the fuel delivery module. It was previously thought that effects of a crash would be most severe on the module when the fuel tank was empty and the module was full with fuel.

The EASIS project clarified typology of dependent failures (Common Cause Failures, Common Mode Failures and Cascading Failures). Typology of dependent failures is a key concept used within safety standards such as IEC61508, or the on-going ISO26262. A presentation of this typology supported with concrete examples will be used to introduce a discussion on dependent failure analysis and bring in the distinction between the concepts of independence and absence of interference. Independence of EE architectural elements is required particularly between two architectural elements implementing a function and its associated safety mechanism. Absence of interference which is less demanding than independence is required to allow architectural elements of different criticality to cohabit (among others, safety-related elements and non-safety-related elements). Typical EE automotive examples will support this discussion

Networking of active and passive safety is the fundamental basis for comprehensive vehicle safety. Situation-relevant information relating to driver reactions, vehicle behavior and traffic environment are fed into a crash probability calculator, which continually assesses the current crash risk and intervenes when necessary with appropriate measures to avoid a crash and reduce potential injuries. This provides effective protection not only for vehicle occupants but also for other, vulnerable road users. As this functionality up till now only relates to the vehicle itself, the next logical step is enhancement leading to the ultimate goal in safety performance, telematics. The integration of this embedded, in-vehicle wireless communication system allows Car-to-Car (C2C) and Car-to-Infrastructure (C2I) functionality for, e.g. hazard warning. This is an integral element of the cascaded ContiGuard® protection measures.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

The transportation industry, and in particular the automotive industry is undergoing the effects of two major events: in 2008 the soaring price of oil and in 2009 the global economic crisis. In addition to these events, new regulations are being signed into law in many countries around the world to reduce, or at least control, CO2 emissions. In parallel, to respond to these challenges, automotive manufacturers and suppliers are developing the internal combustion engine along 3 major trends: Downsizing with integration of turbocharger or supercharger Hybridization : from micro hybrid to full hybrid Low-cost engine for the just required performance These new powertrain systems call for a growing number of combustion modes and separate controls, dependent of the operating point, to satisfy all functional and legislative requirements. Likewise, they require new components which are more and more complex and controllable with greater accuracy.

Electronic thermal management reduces pump and fan power consumption through gains in controllability and efficiency, and also provides for additional control of heat rejection management and variable control of coolant, oil, and engine temperatures. This paper represents the design, bench testing, and wind-tunnel vehicle testing of an advanced system comprised of an electric pump, electronic water flow proportioning valve, 42V alternator, 36V starter, and an electronic control system which commands the performance of the valve, pump, and fan clutch in relation to the cooling demand on a 1999 Volvo VN tractor equipped with a Cummins N14 engine. System design and test data are compared from both the stock cooling system and the advanced thermal management system (ATMS).

Considered in this study by the use of finite element model is a unit of assembled stator and one-way clutch (OWC) housed in a test setup, where the inner chamber is maintained at a given elevated temperature while its exterior housing surfaces are exposed to the room temperature. The two key components of dissimilar metals are assembled through the conventional interference fitting at their interface surfaces to form a friction joint at the room temperature. Due to the difference in the thermal expansion coefficients of two dissimilar materials, the outer component of aluminum from this joint tends to expand more than the inner component of steel when the temperature rises, thus leading to a possible relaxation in joining connection at their interface.

The control of sound fields radiated by vibrating structures in a passenger compartment, (especially structures connected to different organs like the engine powertrain, the fan motor unit, seats, the steering column, electrical motors more and more, etc.) is among the functions of the automotive manufacturers. The absence of physical prototypes in the development phase systems led OEMs1 to use tests results obtained on benches following technical specifications from manufacturers. The transition "bench to vehicle" for vibro- acoustic behaviour sets many challenges that this standard intends to clear up. This standard specifies the experimental method to transpose the dynamic forces generated by the global movements of an active component between the vehicle and a test bench. The efforts are first measured on test benches and then transposed from test bench towards the vehicle. The standard is now a French standard (XP R 19-701) and is submitted to ISO process [1].

With more emphasis on developing a better fuel-economic vehicle, applications of charged air cooler (CAC) in turbo charged gas and diesel engine plays an increasing critical role in both aspects of reduction of engine intake manifold temperature level and increase of intake air density. However, there is a limitation on how far charged air can be cooled when it starts to condensate within the charged air cooler (CAC). In this paper, staring from basic thermodynamics principles, a thermal flow model is developed and explains the physical reasons for the condensation generation inside charged air cooler (CAC) tubes.

In the research project between the Institute of Automotive Engineering (FZD) of the Technische Universität Darmstadt (TUD) and Continental Teves AG & Co. oHG a new modeling concept has been developed. With the aim to enhance the current development process, the brake caliper is modeled based on coupled rigid bodies integrated into a nonlinear system model. Using an explicit interface definition, the number of degrees of freedom is minimized and the calculation of caliper performance is possible over a wide range of parameters. Compared to models based on the Finite Element Method (FEM), fully parameterized geometry from CAD is not necessary, thus the caliper can be optimized for a variation of its geometrical and physical parameters. With this modeling approach, typical performance criteria such as caliper fluid displacement, hysteresis, uneven pad wear and residual torque can be calculated in a virtual bench test.

In the near future the automotive industry shall introduce a wide range of new, high technological functions and applications. These are being driven by the industries demand for a reduction in fuel consumption, pollutant emissions and an overall improvement to vehicle safety. These new demands go together with the spread of electronics and the implementation of more and more electrically driven systems, with medium and high power capabilities. These electrically driven systems either replace previous hydro-mechanical systems, for Power Steering for instance, or allow for the introduction of new functionalities like engine “Start & Stop”. They can even lead to completely new power train architecture like hybrid vehicles for example. With all these systems the demand for more equipment with power electronics, tailored to the automotive industry, rises tremendously.

The US American government introduced a law to mandatorily equip passenger vehicles with rear view cameras. Furthermore, US NCAP presented a test for passenger vehicles to brake on pedestrians while back up. These two circumstances lead to main motivation of the development of the Comfort Backup Assist (CBUA). Nevertheless, more and more passenger cars in general are being equipped with rear view cameras. Rear view system (RVS) allows to deliver a rear-view camera system including a braking functionality which is intended to make the driving mission safer and reduce the number of accidents in parking driving situations. RVS also focus on vehicle safety by reducing accidents while taking reversing/parking scenarios and to provides slow de-acceleration of the vehicle gradually to avoid jerk and increase the ride comfort.

The implementation of the new electronic equipment makes the electrical and electronic architecture more and more complex. Thus technologies such as Power Line Communication constitute alternative solutions to reduce the number of wires and optimize the harness. Taking into account the know how and applications for household use, the power line communication feasibility in automotive domain had to be performed. This paper deals with the essential parameters to be identified in order to provide the appropriate power line modulation. Harness EMC behavior and EMI disturbances inside vehicle are developed in this paper.

The paper presents the Valeo approach to integrate the problem of recycling from the design stage. The first part deals with the reasons for which we have to design a recyclable unit, and in the second part, the technical solutions will be exposed.

To reduce the weight of the front windshield system, a fiber reinforced plastic design for the wiper arm and blade is being investigated. The use of suitable thermoplastics reinforced with short fiberglass allows the elaboration of good stiffness parts by injection moulding. Tests were carried out to show that stiffness depends on the fiberglass concentration and orientation. Likewise the temperature leads a decreasing of mechanical properties. Processing conditions of plastics have significant influence and aim to increase their performances, effectively a distribution in the orientation of fiberglass can be observed in the thermoplastic matrix. Various experimental means are used to characterise the plastic materials.

Driver assistance features have been introduced to the market focusing on basic, independent functional scenarios. The trend is showing that these kinds of products are facing more and more complex scenarios and we are transitioning from single independent functions to a strongly networked system. Some of the drivers for future autonomous vehicles are 360° monitoring by active safety technology and V2X (vehicle to vehicle or vehicle to infrastructure) communication. In the past vehicles were strictly operated by the driver. Advanced driver assistance products added so called feedback features like lane departure warning, forward collision warning, and blind spot monitoring. First steps towards semi-autonomous driving started with the development of active support functions like adaptive cruise control or lane keeping support. Collision mitigation with various authority levels is the next milestone towards automation followed by other, even more advanced, features.

A two pedal drive device has been developped, using a standard dry clutch, an electric motor as an actuator and a microprocessor control. With the help of a compensator spring, a low power, low inertia motor with a fast response can be used. The control characteristic is basically a centrifugal law, with several modifications. Several sensors input information into the microprocessor and compensate for manufacturing tolerances and lining wear. The Electronic Clutch Control has been fitted to different cars and has given optimal results. It can be used in conjunction with manual transmissions, CVTs or other types of transmissions.