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This paper investigates the role that load-limiters play with respect to the performance of occupant protection systems, with focus on performance in frontal crashes. Modern occupant protection systems consist of not just the seat belt, but also airbags, interior vehicle surfaces and vehicle structure. Modern seat belts very often incorporate load-limiters as well as pretensioners. Published research has established that load-limiters and pretensioners increase the effectiveness of occupant protection systems. Some have argued that load-limiters with higher deployment thresholds are always better than load-limiters with lower deployment thresholds. Through testing, modeling and analysis, we have investigated this hypothesis, and in this paper we present test and modeling data as well as a discussion to this data and engineering mechanics to explain why this hypothesis is incorrect.

Load-sensitive hydraulic control systems have demonstrated new potential high efficiency levels. Mobile equipment designs which widely utilize open and closed center circuits are being adapted to total centralized load-responsive stand-by systems to curtail fuel consumption and operating costs. This paper outlines previous art in steering systems and highlights the design concepts required to adapt the steering function to load sensitive variable flow-pressure circuitry. Since the steering function power demands are normally low for corrective maneuvers, it is ideally suited to the environment of a central load-sensitive system. The general concept of a load-sensing steering valve and its relative design role to the other system components will be developed, emphasizing standard meter-in load-sensing technology. The possible new “feathered” and “absolute” type systems are introduced.

Electronic Control Units (ECUs) are typically programmed using external programming devices - frequently called Diagnostic Testers. We propose a system and software architecture that requires no Diagnostic Tester for ECU (re)programming. ECU (re)programming is instead managed by an on-board software component, the Flashware-Reprogramming-Controller. It can reside in any ECU that has sufficient memory and processing power as well as good connectivity to internal networks and external sources from which to receive the software to be installed. Appropriate choices could be modern telematic devices. A second co-located on-board software component - the Installation-Configuration-Controller - is used to supervise the installation of new software releases and to validate their integrity after installation. The proposed architecture can be used for software download into ECUs in development, end-of-line production and after sales.

In this paper, the microstructure-based finite element modeling method is used in investigating the loading path dependence of formability of transformation induced plasticity (TRIP) steels. For this purpose, the effects of different loading path on the forming limit diagrams (FLD) of TRIP steels are qualitatively examined using the representative volume element (RVE) of a commercial TRIP800 steel. First, the modeling method was introduced, where a combined isotropic/kinematic hardening rule is adopted for the constituent phases in order to correctly describe the cyclic deformation behaviors of TRIP steels during the forming process with combined loading paths which may include the unloading between the two consecutive loadings. Material parameters for the constituent phases remained the same as those in the authors' previous study [ 1 ] except for some adjustments for the martensite phase due to the introduction of the new combined hardening rule.

Accurate knowledge of diesel particulate filter (DPF) particulate matter (PM) loading is critical for robust and efficient operation of the combined engine-exhaust aftertreatment system. Furthermore, upcoming on-board diagnostics regulations require on-board technologies to evaluate the status of the DPF. This work describes the application of radio frequency (RF) - based sensing techniques to accurately measure DPF particulate matter levels. A 1.9L GM turbo diesel engine and a DPF with an RF-sensor were studied. Direct comparisons between the RF measurement and conventional pressure-based methods were made. Further analysis of the particulate matter loading rates was obtained with a mass-based total PM emission measurement instrument (TEOM) and DPF gravimetric measurements.

This paper focuses on dynamic analysis and frame optimization of a FSAE racing car frame. Firstly, a Multi-Body Dynamic (MBD) model of the racing car is established using ADAMS/Car. The forces and torques of the mechanical joints between the frame and suspensions are calculated in various extreme working conditions. Secondly, the strength, stiffness and free vibration modes of the frame are analyzed using Finite Element Analysis (FEA). The extracted forces and torques in the first step are used as boundary conditions in FEA. The FEA results suggest that the size of the frame may be not reasonable. Thirdly, the size of the frame is optimized to achieve minimized weight. Meanwhile the strength and stiffness of the frame are constrained. The optimization results reveal that the optimization methodology is powerful in lightweight design of the frame.

Frequency domain methods of analysis are now being used for the evaluation of fatigue for large vehicle systems and these methods offer advantages over equivalent time domain approaches in a number of ways, including analysis efficiency and the usefulness of derived results. One big potential advantage is to be able to do localized sub-component analysis using “cascaded” loads. Such sub-components can be analysed with refined parameters such as more sophisticated damping or a different frequency range. Local parts can also be re-analysed at a different phase in the design program. This paper will demonstrate the approach and show examples of the method.

A previous SAE paper (ref. 1) did a comparative study of automotive system fatigue models processed in the time and frequency domain. A subsequent paper (ref. 2) looked at relative random analysis under base shake loading conditions. This paper proposes to merge these two analysis procedures to implement a new “Loads Cascading” procedure. The objective of this paper will be to show how loads (accelerations, displacements, forces) can be cascaded (transferred) from input load position such as road load data (RLD) body loads to some internal location, for example a battery pack location. Also note that the response from one “module” could form the input to another, therefore, once the loadings are in the frequency domain, the possibility exists to “cascade” the loads through a system. For example, from the chassis, to the subframe to attached components.

Vehicle durability mission loads are an essential and decisive for a reliable life prediction for the component through any durability evaluation. One option to calculate mission loads are multibody models to represent vehicle’s suspension degrees of freedom (dofs) and its dynamic behavior. Generally, trucks have greater wheelbase and then lower natural frequencies than passengers’ vehicles. Therefore are more suitable to dynamic body excitation and the ordinary consideration of a rigid body shell is not relevant. The proposal of this work is to compare the chassis loads considering rigid and flexible frame mounted over the primary suspension. A pseudo-damage was calculated with chassis loads time history for severity assessment. The chose vehicle for the study is an Iveco 4×2 medium range, 6850mm of wheel base, with gross weight of 17ton and leaf springs primary suspension on both: front and rear axles.

This Paper presents the “Frequency Sweep Virtual Analysis” as a tool to help to define the best powertrain mount concept in order to identify the resonance mode frequency on Powertrain System. Applying this method, we can identify proposals to reduce loads in the Powertrain system due the resonance mode and consequently minimize possibility of exceeding material strength. The “Frequency Sweep Virtual Analysis” drives the powertrain mounts design to avoid running many Road Load Data Acquisitions (RLDA) in a trial-and-error process (Cost reduction and timing savings).

The time domain is currently the most widely chosen option in fatigue testing to fully represent random events occurring in multiple simultaneous input channels. In vehicles for example, time domain tests can represent the same conditions of the road, by applying the same loads at the hard points of the vehicle along a time history. The main drawback of this methodology is the extensive testing duration and hardware cost. Time domain based fatigue tests are composed of a complex hardware, which requires servo motors to work, in order to induce the specific amount of load at a specific time window. These tests are time consuming, since they require the same length duration of the event they are reproducing, times the required repetitions. The frequency domain method for fatigue testing, on the other hand, requires simpler hardware, since there are no need for servomotors and the test length is reduced, since there is no need to run the full event times the required repetitions.

Product design engineers have the responsibility for developing a product yielding satisfactory life for some given duty, at a reasonable cost. In the absence of an immediate failure, a product is many times subjected to loading which exceeds the design parameters, resulting in unanticipated short life and possibly poor product acceptance. Often, the ultimate user of a product, with little knowledge of the extensive effects of overloading, justifies this practice with false economics. It is the purpose of this paper to illustrate the relationship of loading to product life. With this basic understanding, it is hoped that products will be used more effectively and not abused.

The chemiluminescence emission intensity can be measured with high temporal resolution, leading to understanding the chemical reaction. Time-series chemiluminescence measurements of OH*, CH* and C2* were carried out to understand flame propagation speed, its thickness and A/F ratio of combustion status. The optical piston head (quartz) allows us to visualize combustion chamber. It is found that the chemiluminescence intensity ratio of CH*/OH* and C2*/OH* can estimate local A/F. The A/F measured by O2 sensor was used for evaluation and the results indicate this method can be applicable to estimate A/F.

The influence of variable air-fuel ratio inside a spark ignition engine is examined by the use of an ionization sensor. The measured ion currents are used for predicting the local air-fuel ratio in the vicinity of the spark plug. In order to support the results, a theoretical analysis has been made. An instationary chemical kinetic model burning a mixture of iso-octane and n-heptane is used for the calculations. The results are used to reconstruct the crank angle resolved ion current that has been measured in an engine. This technique has been developed in order to offer a supplementary low-cost facility of controlling the air-fuel ratio within the combustion chamber of an engine.

This paper describes a numerical study of the effect of hollow crankshafts on crankshaft local strength and durability as well as slider bearing contact behavior. Crankshaft dynamic simulation for durability is still a challenging task, although numerical methods are already worldwide established and integrated part of nearly every standard engine development process. Such standard methods are based on flexible multi-body dynamic simulation, combined with Finite Element analysis and multi-axial fatigue evaluation. They use different levels of simplification and consider the most influencing phenomena relevant for durability. Lightweight design and downsizing require more and more detailed methods due to higher deformation of the crankshaft. This is especially true for hollow shafts, as present in motorsport design or aerospace applications, but also for standard engine having high potential for significant weight savings.

The paper presents the view of a major manufacturer of Automotive electricals and electronics. It shows this industry as part of the Australian environment, how it fits into the global automotive scene and points out where our challenges lie. The capabilities of the industry in the R&D field as well as the application Engineering areas are explained. On the manufacturing side, an overview of the state of the art of producing electronic control modules is provided. The approaches and equipment selected in Australia, as governed by manufacturing volumes and economics, are described. An important aspect is the link between the highly sophisticated manufacturing processes and equipment on one hand and quality assurance and reliability on the other. The paper closes with an outlook towards future electronic systems expected to be used in Australia.

Automobile fires account for the majority of vehicle fires and vehicle fire deaths. Fires involving larger trucks resulted in a disproportionate share of vehicle fire losses. Although bus fires are less common, they have a much higher rate of fire based on distance driven. Bus fires have the potential to endanger a larger number of passengers. Any efforts to evaluate the merits of proposed fire safety improvements require an understanding of how many fires and deaths are presently occurring and how many might be prevented with the proposed improvements. Data from the U.S. Fire Administration's National Fire Incident Reporting System (NFIRS) and the National Fire Protection Association's (NFPA's) fire department survey were used to estimate the frequency and associated losses of such fires attended by local U.S. fire departments, and the major factors in these fires and losses.

We present an experimental investigation of the local flame front characteristics as function of the distance between the flame front and the piston. The objective of this paper is to provide some experimental data about the flame characteristics at the approach of the piston. The transparent engine speed is fixed at 2000 rpm and air-methane mixture was used with an equivalence ratio equal to 0.9. PLIF acetone imaging was acquired to estimate first the curvature, the curvature radius and the normal direction orientation of the local contours as function of the flame-piston distance. A discontinuity in these parameters appears when the distance is less than 1 mm. Secondly we apply local roughness analysis system to estimate the local fractal dimension of the flame front. We conclude that fractal dimension changes rapidly at 2.5 mm from the piston. A logarithm law was found to define the fractal dimension as function of flame-piston distance.

A local Gaussian process regression approach is presented, which allows to model nonlinearities of internal combustion engines more accurate than global Gaussian process regression. By building smaller models, the prediction of local system behavior improves significantly. In order to predict a value, the algorithm chooses the nearest training points. The number of chosen training points depends on the intensity of estimated nonlinearity. After determining the training points, a model is built, the prediction performed and the model discarded. The approach is demonstrated with a benchmark system and air charge test bed measurements. The measurements are taken from a turbocharged SI gasoline engine with both variable inlet valve lift and variable inlet and exhaust valve opening angle. The results show how local Gaussian process regression outmatches global Gaussian process regression concerning model quality and nonlinearities in particular.