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This paper presents a methodology and tool that stochastically generates drive cycles based on measured data, with the purpose of testing and benchmarking light duty vehicles in a simulation environment or on a test-bench. The WLTP database, containing real world driving measurements, was used as input data. Consequently cycles that contain typical accelerations per velocity and road types are generated, such that these cycles are representative to real driving behavior. The stochastic drive cycle generator is developed in Matlab and is based on Markov processes. Two separate stochastic generators are used: one for generating the road type and one for generating the vehicle acceleration. First, a random road type profile is generated from the four different road types that are considered in the WLTP database: urban, rural, motorway and high-motorway, each of them with sub-road types based on different velocity bins.

The European Union road transport CO2 emissions regulation foresees mandatory targets for passenger vehicles. However, several studies have shown that there is a divergence between official and real-world values that could range up to 40% compared to the NEDC reference value. The introduction of the Worldwide Harmonized Test Protocol (WLTP) limited this divergence, but it is uncertain whether it can adequately address the problem, particularly considering future evolutions of vehicle technology. In order to address this issue, the recent EU CO2-standards regulation introduces the monitoring of on-road fuel consumption and subsequently CO2 emissions by utilizing On-Board Fuel Consumption Meters (OBFCM). In the near future, all vehicles should provide instantaneous and lifetime-cumulative fuel consumption signals at the diagnostics port. Currently, the fuel consumption signal is not always available.

Up to now, reduction of fuel consumption of vehicles equipped with CVT transmission has not been exploited to its full potential due to the reduced driveability when driving the optimum efficiency engine operating points. An ISG system with torque boost capabilities can be used to restore this driveability. This paper discusses the goals, the CAE simulation tool, the methodology used in the preparative study for evaluation and dimensioning of a CVT-ISG concept, as well as the simulation results. The conclusions, generated from numerous simulations, provide vital information for the component selection, and for the development of the powertrain management system.

The importance of automotive comfort is increasing, both socially and economically. Especially professional drivers often have comfort-related physical complaints, such as lower back pain. In addition, car manufacturers can use comfort to distinguish their cars from their competitors. However, the development and design of a new, more comfortable car seat is very time consuming and costly. The use of computer models of human and seat could facilitate this process. MADYMO human and seat models offer the possibility to predict comfort. This paper describes the application of the MADYMO multi-body 50th percentile human model for determination of human-seat interaction in vertical vibrations. The validation of the human model is based on volunteer tests with both a rigid seat and a standard car seat. The human model shows a good correlation with the volunteers.

The introduction of a new comfortable car seat or interior is a time consuming and costly process for car and seat manufacturers. The application of numerical models of human and seat could facilitate this process. Vertical vibrations and seat pressure distributions are two objective parameters that have been related to the subjective feeling of (dis)comfort that can be predicted by numerical tools. In this paper, human models suitable for prediction of human behaviour in vertical vibrations and seat pressure distributions are applied in a seat sensitivity study. The objective of this paper is to evaluate the applicability of the human models as design tools for car and seat developers in an early stage of the design process. The sensitivity of the output of the models for variations in seat characteristics for seat developers in the design process of a new comfortable car seat has been studied.

Injuries to the knee-thigh-hip (KTH) complex in frontal motor vehicle crashes are of substantial concern because of their frequency and potential to result in long-term disability. Current frontal impact Anthropometric Test Dummies (ATDs) have been shown to respond differently than human cadavers under frontal knee impact loading and consequently current ATDs (and FE models thereof) may lack the biofidelity needed to predict the incidence of knee, thigh, and hip injuries in frontal crashes. These concerns demand an efficient and biofidelic tool to evaluate the occurrence of injuries as a result of KTH loading in frontal crashes. The MADYMO human finite element (FE) model was therefore adapted to simulate bone deformation, articulating joints and soft tissue behavior in the KTH complex.

Interaction of the human arm and deploying airbag has been studied in the laboratory using post mortem human subjects (PMHS). These studies have shown how arm position on the steering wheel and proximity to the airbag prior to deployment can influence the risk of forearm bone fractures. Most of these studies used older driver airbag modules that have been supplanted by advanced airbag technology. In addition, new numerical human body models have been developed to complement, and possibly replace, the human testing needed to evaluate new airbag technology. The objective of this study is to use a finite element-based numerical (MADYMO) model, representing the human arm, to evaluate the effects of advanced driver airbag parameters on the injury potential to the bones of the forearm. The paper shows how the model is correlated to Average Distal Forearm Speed (ADFS) and arm kinematics from two PMHS tests.

Two of the main design objectives for car interiors are comfort and safety. These aspects are both determined by the seating position of the occupant. Seat manufacturers use the SAE Three-Dimensional H-Point Machine™ to measure seating positions to design, audit, and benchmark seats. The seating positions measured with the H-Point Machine form the basis of a seat design, including comfort and safety aspects. Currently, the seat design process is largely based on prototype testing, which makes this process time-consuming and expensive. Consequently, there is a large demand for efficient design tools that enable an optimal combination of seating comfort and safety aspects. Numerical modeling provides an efficient means to optimally combine various seat design characteristics prior to prototype testing, thereby reducing design costs and time-to-market.

With the adoption of the Worldwide harmonized Light Vehicles Test Procedure (WLTP) and the Real Driving Emissions (RDE) regulations for testing and monitoring the vehicle pollutant emissions, as well as CO2 and fuel consumption, the gap between real world and type approval performances is expected to decrease to a large extent. With respect to CO2, however, WLTP is not expected to fully eliminate the reported 40% discrepancy between real world and type approval values. This is mainly attributed to the fact that laboratory tests take place under average controlled conditions that do not fully replicate the environmental and traffic conditions experienced over daily driving across Europe. In addition, any uncertainties of a pre-defined test protocol and the vehicle operation can be optimized to lower the CO2 emissions of the type approval test. Such issues can be minimized in principle with the adoption of a real-world test for fuel consumption.

The paper describes the development of a modelling approach to simulate the effect of the new Worldwide harmonized Light duty Test Procedure (WLTP) on the certified CO2 emissions of light duty vehicles. The European fleet has been divided into a number of segments based on specific vehicle characteristics and technologies. Representative vehicles for each segment were selected. A test protocol has been developed in order to generate the necessary data for the validation of the vehicle simulation models. In order to minimize the sources of uncertainty and the effects of flexibilities, a reference “template model” was developed to be used in the study. Subsequently, vehicle models were developed using AVL Cruise simulation software based on the above mentioned template model. The various components and sub-modules of the models, as well as their input parameters, have been defined with the support of the respective OEMs.

Pedestrians and cyclists are the most unprotected road users and their injury risk in case of accidents is significantly higher than for other road users. The understanding of the influence and sensitivity between important variables describing a pedestrian crash is key for the development of more efficient and reliable safety systems. This paper reflects the related work carried out within the AsPeCSS project. The results summarized out of virtual and physical tests provide valuable information for further development. 1168 virtual and 120 physical tests were carried out with adult and child pedestrian headform as well as upper and lower legform impactors representatives of 4 different vehicle front geometries in a wide range of impact speeds, angles and locations. This test matrix was based on previous work carried out within the AsPeCSS project.

The present work investigates a number of recalibration possibilities of a common rail turbocharged diesel engine, aiming at the improvement of its emissions performance and fuel consumption (FC), with Hydrotreated Vegetable Oil (HVO). Initially, steady-state experimental data with nominal engine settings revealed HVO benefits as a drop-in fuel. Under these conditions, pure HVO results in lower engine-out PM emissions, lower CO2 emissions, and lower mass-based FC, while the respective NOx emissions present a mixed trend. In mid loads and speeds NOx emissions of HVO are lower while at higher loads and speeds are slightly higher compared to conventional diesel. At a second step, a combustion model was developed, in order to investigate the possible re-adjustments of IT (Injection Timing) and EGR (Exhaust Gas Recirculation) settings in order to exploit HVO’s properties for further reduction of emissions and FC.

The Vehicle Energy Consumption calculation Tool (VECTO) is used for the official calculation and reporting of CO2 emissions of HDVs in Europe. It uses certified input data in the form of energy or torque loss maps of driveline components and engine fuel consumption maps. Such data are proprietary and are not disclosed. Any further analysis of the fleet performance and CO2 emissions evolution using VECTO would require generic inputs or reconstructing realistic component input data. The current study attempts to address this issue by developing a process that would create VECTO input files based as much as possible on publicly available data. The core of the process is a series of models that calculate the vehicle component efficiency maps and produce the necessary VECTO input data. The process was applied to generate vehicle input files for rigid trucks and tractor-trailers of HDV Classes 4, 5, 9 and 10.

Six European laboratories have evaluated the biomechanical response of the new advanced frontal impact dummy THOR-alpha with respect to the European impact response requirements. The results indicated that for many of the body regions (e.g., shoulder, spine, thorax, femur/knee) the THOR-alpha response was close to the human response. In addition, the durability, repeatability and sensitivity for some dummy regions have been evaluated. Based on the tests performed, it was found that the THOR-alpha is not durable enough. The lack in robustness of the THOR-alpha caused a problem in completing the full test program and in evaluating the repeatability of the dummy. The results have demonstrated that the assessment of frontal impact protection can be greatly improved with a more advanced frontal impact dummy. Regarding biofidelity and injury assessment capabilities, the THOR-alpha is a good candidate however it needs to be brought up to standard in other areas.

Injury assessment reference values (IARV) predicting neck injuries are currently not available for side facing seated aircraft passengers in crash conditions. The aircraft impact scenario results in inertial loading of the head and neck, a condition known to be inherently different from common automotive side impact conditions as crash pulse and seating configurations are different. The objective of this study is to develop these IARV for the European Side Impact Dummy-2 (ES-2) previously selected by the US-FAA as the most suitable ATD for evaluating side facing aircraft seats. The development of the IARV is an extended analysis of previously published PMHS neck loads by identifying the most likely injury scenarios, comparing head-neck kinematics and neck loads of the ES2 versus PMHS, and development of injury risk curves for the ES2. The ES2 showed a similar kinematic response as the PMHS, particularly during the loading phase.