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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.

During the development phase of any Powertrain component/subsystem for a conventional ICE or an XEV (Hybrid/Battery Electric Vehicle), system Energy efficiency and Performance improvement simulations are a very important step to prove the worthiness of the product before we can advance to building Prototypes, Vehicle level Integration, Testing, analysis and benefit’s evaluation phases. This work describes how two simulation tools have been leveraged effectively for Energy efficiency and Performance simulations for an Electric vehicle. Schaeffler has an internal Physical Modelling Tool (PMT) for building vehicle level models. This tool has readymade physical blocks for various Mechanical and Electrical components. These blocks can be parameterized as per required specifications. The powertrain subsystems like the Battery, BLDC Motor, Vehicle Dynamics and the Multi-speed transmission consisting of various mechanical elements have been modelled and parametrized using this tool.

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.

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.

Contact rubber seals have been extensively employed in bearing systems in order to avoid internal dusty contamination and grease leakage. As an inherent consequence, heat and friction losses arises from the sliding contact of these seals. Indeed, the increasing speed of mechanisms, warranted by the desire for increase power, leads to higher operating temperatures and reduced fluid viscosities, associated with higher pressures, what cause an increasing tendency for fluids to leak. Such characteristics require the design of high performance sealing systems to avoid grease leakage and bearing contamination, but at low rates of friction and heat generation. [1] By means of Finite Element Analysis and Experimental Procedures such as DoE, this study aims to isolate and evaluate the influence of the seal design and its several parameters on the friction variables such as resistance torque.

The water and dust contamination has being studied as an important factor for the components life. For the evaluation of water and dust, it is important that a good method of analysis has been defined. This paper will present a method used to evaluate the grease contamination with dust and water and the actions made to improve the analysis of grease. In order to evaluate the water content in the grease, it was used the Karl Fischer titration. This method determines trace amount of water in a sample. A restriction of this analysis is the grease sample amount, which could not be fully titrated. So just part of the grease (contaminated with water) is analyzed and due to the heterogeneity of the grease and water mixture, this small sample of grease does not necessarily have the same amount of water than the whole grease.

The basic function of the clutch, transmitting torque when running, interrupting the flow of power between the engine and gearbox in the changing gears and stopping and protecting the engine and transmission against overload and dampen vibration transmission. The plateau clutch with spring membrane is the system used today. The modern clutches are small and save space in the engine compartment reducing the total weight of transmission, minimizing the resistance to rotation of the motor, providing less mechanical losses. The construction and assembly of the membrane spring clutch assembly is very important, since misalignment of reeds could result in chatter or vibration in clutch pedal, along with the hard drive of the pedal, which can also generate a deformation of the components and thus premature wear of the clutch.

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.

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.

The accuracy of the simulation of NVH behavior is strongly dependent on parameters such as stiffness and damping of the structure as they have a direct influence on the results. This paper is focused on a straightforward method of achieving and implementing acceptably accurate damping values in joints in the early development phase. With emphasis on ease of use and independent software, a Kelvin-Voigt model is used to generate damping behavior. Based on a modal test, damping parameters are achieved and the base model is calibrated. Using this as a starting point, damping parameters and topographical values are optimized with the focus being on minimizing the simulated radiated acoustic power. The method is represented on a simplified disc structure and results are discussed.

Compressed natural gas (CNG) is an attractive, alternative fuel for spark-ignited (SI), internal combustion (IC) engines due to its high octane rating, and low energy-specific CO2 emissions compared with gasoline. Directly-injected (DI) CNG in SI engines has the potential to dramatically decrease vehicles’ carbon emissions; however, optimization of DI CNG fueling systems requires a thorough understanding of the behavior of CNG jets in an engine environment. This paper therefore presents an experimental and modeling study of DI gaseous jets, using methane as a surrogate for CNG. Experiments are conducted in a non-reacting, constant volume chamber (CVC) using prototype injector hardware at conditions relevant to modern DI engines. The schlieren imaging technique is employed to investigate how the extent of methane jets is impacted by changing thermodynamic conditions in the fuel rail and chamber.

Accuracy of clutch torque model which converts target torque to target stroke is essential to control the dry clutch system. Continuous Adaptation algorithm requires micro slip control during in-gear driving. Clutch judder during micro slip control can cause detrimental effect on the output of controller as slip speed is calculated by deviation of engine speed and clutch speed. Conventional approach to avoid clutch judder is using low pass filter to the input of controller which is slip speed. But this affect to the overall response time of slip controller. In this paper, signal processing algorithm is design and tested for the clutch speed(Input shaft speed). With low pass filter in clutch speed, clutch judder signal is decreased but overall time delay creates static error during acceleration. Several phase advance algorithm is designed to overcome the static error during acceleration without disadvantage of decreasing clutch judder signal.

Global automotive fuel economy and emissions pressures mean that 48 V hybridisation will become a significant presence in the passenger car market. The complexity of powertrain solutions is increasing in order to further improve fuel economy for hybrid vehicles and maintain robust emissions performance. However, this results in complex interactions between technologies which are difficult to identify through traditional development approaches, resulting in sub-optimal solutions for either vehicle attributes or cost. The results presented in this paper are from a simulation programme focussed on the optimisation of various advanced powertrain technologies on 48 V hybrid vehicle platforms. The technologies assessed include an electrically heated catalyst, an insulated turbocharger, an electric water pump and a thermal management module.

Indian Two-wheeler market is the biggest in the world. In two-wheeler segment, scooters have seen a growth of about 27% year-on-year in 2015 and the trend continues in 2016. This healthy growth is due to their ease of handling and operation. This can be majorly attributed to the use of a Continuously Variable Transmission (CVT). While the CVT does offer considerable comfort to rider due to an absence of manual gear-shifting and clutch operation, it also suffers from the drawback of dragging the engine during deceleration phases, which adversely affects fuel efficiency of scooters with carburetor engine, which are quite common in India. Average Fuel efficiency of scooters is ~ 25% less compared to motor bikes with same engine configuration. Also, vibrations due to the engine drag are noticeable.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Improving vehicle performance in terms of both torque and power is a strong customer need in both conventional and electric vehicles. In this work, different two speed automatic transmission (AT) concepts are developed to improve the energy efficiency and performance of battery electric two wheelers. Developed transmission systems are simple, compact and cost effective and results in relatively high energy efficiency of an electric motor. The unique shift control strategy ensures motor to operate at higher efficiency zones to minimize the overall energy consumption. Virtual simulations of electric vehicle were carried out for different driving conditions and optimal transmission ratios were determined. Mechanical behaviors such as gear shift characteristics, linear and angular velocities, inertial forces of each components are analyzed by using Multi body dynamics simulation. Forces predicted here are further used for durability studies of these components.

Manual transmissions play a dominant role in India with a market share of more than 90%. Any technology that improves their fuel consumption and their comfort for end users is highly welcome if it is affordable regarding “value for money”. Schaeffler offers a technology to meet these challenges with the concept of Electronic Clutch Management (ECM). By implementing an intelligent mechatronic clutch actuator with specific, integrated sensors directly inside the actuator, this development prepares the ground for a new era that says farewell to the clutch pedal and achieves the target of using a 2-pedal system.

Since several decades, passenger cars and light duty vehicles (LDV) with spark-ignited engines reach full pollutant conversion during warm up conditions; the major challenge has been represented by the cold start and warming up strategies. The focus on technology developments of exhaust after treatment systems have been done in the thermal management in order to reach the warm up conditions as soon as possible. A new challenge is now represented by the Real Driving Emission (RDE) Regulation as this bring more various, and not any longer cycle defined, cold start conditions. On the other hand, once the full conversion has been reached, it would be beneficial for many Exhaust After Treatment System (EATS) components, e.g. for overall durability if the exhaust gas temperature could be lowered. To take significant further emission steps, approaching e.g. zero emission concepts, we investigate the use of Electrical Heating Catalyst (EHC) also including pre-heating.

Riveting is a process used to fasten printed circuit board to housing that offers several advantages compared to screws. This involves a cylindrical pin that protrudes from the housing being compressed with a concave tool to produce a rivet head that fills the PCB hole and holds it in place over service life of the component. The process as performed currently in-house uses parameters that have not been optimized. Testing has revealed that the process is subjecting the PCB to surface strains higher than 1000μɛ which is the limit as recommended by standards. Exceeding this limit reduces the reliability of electrical components and increases risk of field failures. This risk can be mitigated by improving the riveting process parameters to prevent high strain from reaching components. Having a finite element model for high deformation problems is an essential prerequisite to explore riveting process improvement.