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One dimensional linear acoustics network models are commonly used for the acoustic design of intake and exhaust systems. These models are advantageous since they allow the characterization of the scattering matrices for individual elements, independent of the upstream or downstream components. For an intake or exhaust assembly, the individual elements can be combined by a simple multiplication of the individual matrices to assess the propagation characteristics of the whole system under consideration. The determination of the scattering matrix coefficients can be carried out in an analytical, numerical or experimental way. Since the analytical methodologies are limited to uniform or simplified mean flow representation and the experimental two-port determination is expensive and time-consuming, a numerical method using the time domain Linearized Euler Equations is proposed in this paper.

As the demand for enhanced comfort, safety and differentiation with new features continues to grow and as electronics and software enable most of these, the number of electronic units or components within automobiles will continue to increase. This will increase the overall system complexity, specifically with respect to the number of controller actuators such as e-motors. However, hard constraints on cost and on physical boundaries such as maximum power dissipation per unit and pin-count per unit/connector require new solutions to alternative system partitioning. Vehicle manufacturers, as well as system and semiconductor suppliers are striving for increased scalability and modularity to allow for most cost optimal high volume configurations while featuring platform reuse and feature differentiation. This paper presents new semiconductor based approaches with respect to technologies, technology mapping and assembly technologies.

A mechatronic approach to implementing a BLDC motor drive control system is described. The partitioning method used allows the motor power to be scaled from around 100 watts to 1 kilowatt. The chosen approach maps the required electronic functionality to different existing front-end technologies. By drawing on vast experience with back-end technologies, especially chip-on-chip assembly, it is possible to implement a system in a one-package solution. The advantages of each technology are used to achieve a cost-effective, space-saving solution.

This paper describes the prediction process of wheel forces and moments via indirect transfer path analysis, followed by an analysis of the influence of wheel variants and suspension modifications. It proposes a method to calculate transmission of noise to the vehicle interior where wheel forces and especially moments were taken into account. The calculation is based on an indirect transfer path analysis with geometrical modifications of the frequency response functions. To generate high quality broadband results, this paper also points out some of the main clearance cutting criteria. The method has been successfully implemented to show the influence of wheel tire combinations as well as the influence of suspension modifications. Case studies have been performed and will be presented in this paper. Operational noise and vibration measurements have been carried out on Daimler NVH test tracks. The frequency response functions were estimated in an acoustic laboratory.

The increasing shift of drive operation towards efficient engine operation points at very low engine speeds demands a concerted design and tuning of engine, drive-train, assembly attachment and body to avoid annoying low speed boom noise. An additional challenge in this area of conflict is the increasing torque of modern engines at low engine speeds. As an example for a standard passenger car, the modes of operation, which may lead to low speed boom noise, are described. Setting levers along the complete chain of effect are characterised - from cylinder pressure up to the radiating surfaces of the interior. To achieve challenging NVH-targets the application of nonlinear simulation systems is indispensable, in particular in the concept phase of a vehicle. The use of multi-body simulation is presented for a concentrated NVH-optimisation of powertrain and rear axle vibration behaviour to reduce low-speed boom noise. On entire vehicle level hybrid simulation models are useful.

Rising oil prices and increasing strict emission legislation force vehicle manufacturers to reduce fuel consumption of future vehicles. In order to meet this target, the process of converting fuel into useable energy and the use of this energy by the different energy-consuming vehicle's subsystems have to be examined. Vehicles' subsystems consist of energy-supplying, energy-consuming, and in some cases energy-storing components. Due to the high complexity of these systems and their interaction, optimization of their energy efficiency is a challenging task. By introducing individual operational strategies for each subsystem, it is possible to increase the energy efficiency for a specific function. To further improve the vehicle's overall energy efficiency, holistic control strategies are introduced that distribute the energy between the subsystems intelligently.

The number of safety critical automotive applications employing high current brushless motors continues to increase (Steering, Braking, and Transmission etc.). There are many benefits when moving from traditional solutions to electrically actuated solutions. Some of these benefits can include increased fuel economy, simplified vehicle installation and packaging, increased feature set, improved safety and/or convenience, simplified unit assembly and modular testability prior as well as during vehicle manufacturing. The trend to implement brushless motors in these applications (which require electronically controlled commutation) has also brought with it the need for powerful inverters, which primarily consist of Power MOSFETs and MOSFET Driver ICs. This paper reviews the challenges associated with the design of safety critical electronic systems which combine sensing, control and actuation.