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Today's calibration process for ECU functions is often based on a wide variety of proprietary tools and individual expert knowledge of calibration engineers. Automatic calibration with an industrialized tool chain provides high potential to reduce testbed time, calibration time and project costs. Based on an efficient measurement procedure in combination with an offline calibration methodology the capability is validated, e.g. for calibrating the ECU function “Air Charge Determination” for SI engines. In this article the implementation, in a series production project of a major OEM, is shown. The whole workflow - which can also be applied to other calibration tasks - will be described in detail. Presented here will be how General Motors Corporation (GM) is able to speed up the calibration of the ECU functions, whilst maintaining at least the same quality of calibration as before, by the use of this tool chain.

At the moment the documentation of failure inhibition matrices and the fault path management for different controller types and different vehicle projects are mainly maintained manually in individual Excel tables. This is not only time consuming but also gives a high potential for fault liability. In addition there is also no guarantee that the calibration of these failure inhibition matrices and its fault path really works. Conflicting aims between costs, time and fault liability require a new approach for the calibration, documentation and testing of failure inhibition matrices and the complete Diagnostic System Management (DSM) calibration. The standardization and harmonization of the Diagnostic System Management calibration for different calibration projects and derivates is the first step to reduce time and costs. Creating a master calibration for the conjoint fault paths and labels provides a significant reduction of efforts.

For noise quality and brand sound design of passenger cars a unique software tool is currently used by our clients world-wide to evaluate and optimise the interior noise quality and brand sound aspects of passenger cars on an objective basis. The software tools AVL-VOICE and AVL-COMFORT are designed for the objective analysis of interior noise quality, for benchmarking, for the definition of noise quality targets and most important for effective vehicle sound engineering. With this tool, the target orientated implementation of the required interior noise quality or brand sound by predictable hardware modifications into passenger cars - for tailor made joy of driving - becomes feasible. The use of this tools is drastically reducing vehicle evaluation time and sound engineering effort when compared with traditional jury subjective evaluation methods and standard acoustic NVH optimisation procedures.

Future demands regarding emissions, fuel consumption and driveability lead to complex engine and power train control systems. The calibration of the increasing number of free parameters in the ECU's contradicts the demand for reduced time in the power train development cycle. This paper will focus on the automatic, unmanned closed loop optimization of driveability quality on a high dynamic engine test bed. The collaboration of three advanced methods will be presented: Objective real time driveability assessment, to predict the expected feelings of the buyers of the car Automatic computer assisted variation of ECU parameters on the basis of statistical methods like design of experiments (DoE). Thus data are measured in an automated process allowing an optimization based on models (e.g. neural networks).

Wall flow particulate filters have been used as a standard exhaust aftertreatment device for many years. The interaction of particulate matter (PM) regeneration and catalytically supported reactions strongly depends on the given operating conditions. Temperature, species concentration and mass flow cause a change from advective to diffusive-controlled flow conditions and influence the rate controlling dominance of individual reactions. A transient 1D+1D model is presented considering advective and diffusive transport phenomena. The reaction scheme focuses on passive PM conversion and catalytic oxidation of NO. The model is validated with analytical references. The impact of back-diffusion is explored simulating pure advective and combined advective diffusive species transport. Rate approaches from literature are applied to investigate PM conversion at various operating conditions.

A calibration and validation workflow will be presented in this paper, which utilizes common static global models for fuel consumption, NOx and soot. Due to the applicability for warm-up tests, e. g. New European Driving Cycle (NEDC), the models need to predict the temperature influence and will be fitted with measuring data from a conditioned engine test bed. The applied model structure - consisting of a number of global data-based sub-models - is configured especially for the requirements of multi-injection strategies of common rail systems. Additionally common global models for several constant coolant water temperature levels are generated and the workflow tool supports the combination and segmentation of global nominal map with temperature correction maps for seamless and direct ECU setting.

Dynamometer (dyno) durability testing plays a significant role in reliability and durability assessment of commercial engines. Frequently, durability test procedures are based on warranty history and corresponding component failure modes. Evolution of engine designs, operating conditions, electronic control features, and diagnostic limits have created challenges to historical-based testing approaches. A physics-based methodology, known as Load Matrix, is described to counteract these challenges. The technique, developed by AVL, is based on damage factor models for subsystem and component failure modes (e.g. fatigue, wear, degradation, deposits) and knowledge of customer duty cycles. By correlating dyno test to field conditions in quantifiable terms, such as customer equivalent miles, more effective and efficient durability test suites and test procedures can be utilized. To this end, application of Load Matrix to a heavy-duty diesel engine is presented.

Increasing requirements for the result quality of exhaust emission analyzers and state of the art analyzer technology require a new point of view regarding measuring range definitions and linearization procedures. To make best use of the power of this analyzer technology, linearization procedures need reconsideration. In certification laboratories, legislation defines the procedures to linearize an exhaust emission analyzer more or less stringently. On the other hand, on testbeds for development purposes there are many possibilities for making use of today's improved analyzers. However, procedures are often used in development labs that are very similar to those mentioned in the legislation. For some measurement purposes it is necessary to leave these procedures regarding measuring ranges and their specifications behind. The exhaust gas analyzing system has to provide consistent result quality during the whole test procedure.

Over the past few years, the fuel mass measurement gained in importance to record the consumed fuel mass and the specific fuel consumption [g/kWh] with high accuracy. Measuring instruments, such as positive displacement meters, methods based on the burette or the Wheatstone bridge mass flow meter measure either the volumetric flow and a temperature-dependant fuel density correction is necessary or they have old technology and therefore poor accuracy and repeatability. A new-generation Coriolis sensor featuring an ideal measurement range for engine test beds but still with flow depending pressure drop has been integrated in a fuel meter to ensure that no influence is given to the engine behaviour for example after engine load change. The new Coriolis meter offers better accuracy and repeatability, gas bubble venting and easy test bed integration. For returnless fuel injection systems the fuel system supplies the fuel pressure.

Over the past 30 years, simulation of the N&V (Noise and Vibration) behaviour of automotive drivelines became an integral part of the powertrain development process. With current and future HEVs (Hybrid-Electrical Vehicles), additional phenomena and effects have entered the scene and need to be taken into account during layout/design as well as optimization phase. Beside effects directly associated with the e-components (namely electric whistle and whine), torque changes caused by activation/deactivation of the e-machine give rise to vibration issues (e.g. driveline shuffle or clonk) as well. This is in particular true for transient operation conditions like boosting and recuperation. Moreover, aspects of starting the Internal Combustion Engine (ICE) using the built-in e-machine in conjunction with the dynamic behaviour of torsional decoupling devices become increasingly important. In order to cope with above-mentioned effects a multi-physics simulation approach is required.

Increasing demands for safety, security, and certifiability of embedded automotive systems require additional development effort to generate the required evidences that the developed system can be trusted for the application and environment it is intended for. Safety standards such as ISO 26262 for road vehicles have been established to provide guidance during the development of safety-critical systems. The challenge in this context is to provide evidence of consistency, correctness, and completeness of system specifications over different work-products. One of these required work-products is the hardware-software interface (HSI) definition. This work-product is especially important since it defines the interfaces between different technologies. Model-based development (MBD) is a promising approach to support the description of the system under development in a more structured way, thus improving resulting consistency.