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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.

Proper performance of a vehicle's suspension system is required to ensure safe, comfortable operation of a vehicle. A suspension-testing device that can determine the condition of the suspension system, specifically the dampers, has been designed. The tests described by this paper seek to evaluate the performance of the device by testing vehicles and comparing to other methods of measuring suspension system performance that are currently in use. The suspension-testing device has the ability to discover degraded performance of the suspension system through a 2-minute test with the vehicle in operating condition.

As aluminum automotive component suppliers continue to gain market share, they are doing so in areas that have been traditional holdouts for iron and steel components. Structural and safety critical components require a fluoroscopic (x–ray) inspection to verify part quality. This inspection process has traditionally been a labor and capital–intensive process utilizing an operator inspecting an x–ray image on a monitor. Multiple manned inspection units are often required due to the high volume, high throughput nature of the industry and the relative slow speed of a human inspector. With the advent of digital imaging techniques and image recognition algorithms, it is now feasible to remove the human from the inspection process. This enables companies to reduce manpower and improve the consistency of quality reaching the consumer. This paper analyzes the existing state of automatic digital radiography available to the automotive supplier industry.

This paper describes the capabilities and use of in-vehicle data acquisition and analysis tools that are being developed to help calibration engineers develop and refine vehicle calibrations for good driveability performance. The paper describes the functionality of the tools and gives examples of their use.

This paper is the third part of a series of vehicle tests designed and conducted in order to further the understanding of vehicle handling and responses associated with a tire disablement event. The first two parts were published in SAE 970954 Drag and Steering Effects of Under Inflated and Deflated Tires [1], and SAE 1999-01-0447 Drag and Steering Effects from Tire Tread Belt Separation and Loss [2]. All of the test results included herein are presented in a manner to facilitate direct comparison to the previous test programs. Under inflated or deflated tires are known to cause increased forward drag and lateral steering effects on vehicles. These effects are commonly suggested to be the cause of driver loss of control and subsequent vehicular accidents. The increased drag and induced steering effects of under inflated and deflated tires are frequently an issue in an accident reconstruction.

This paper applies a known benchmark set for the performance of vehicular collision algorithms to two impact and trajectory reconstruction algorithms, for the case of partial braking. One algorithm assumes no vehicle movement during the collision (instantaneous impact) and no structural recovery (plastic crush; no restitution); the other revokes these conventional simplifications. The paper presents statistical comparison of each algorithm with the benchmark set, hence with one another. A reference family of reasonably well simulated 2-car impacts in four classes, previously offered by Woolley and Kinney for the 100% braked case only, is here extended to the case of partial (40%) braking. As with the original (1994) set, authors of accident reconstruction programs are invited to demonstrate the performance of their programs in terms of deviation from this available, if arbitrary, benchmark set of reference cases.

A new method has been developed for measuring the thermal conductivity of polymeric materials. The method is based on heat capacity measurements made using modulated differential scanning calorimetry (MDSC). This technique is capable of quantitatively separating reversible (heat capacity related) thermal events from nonreversible thermal events. The advantages of the method are that it is fast and leads to accurate thermal conductivity measurements. The new method was used to measure thermal conductivity of 43 polymeric parts. The results show that crystalline polymers have higher thermal conductivity than amorphous polymers. For any one polymer, thermal conductivity increases with an increase in filler concentration.

Traditional vehicle simulations use two methods of modeling driver inputs, such as steering and braking. These methods are broadly categorized as “Open Loop” and “Closed Loop”. Open loop methods are most common and use tables of driver inputs vs time. Closed loop methods employ a mathematical model of the driving task and some method of defining an attempted path for the vehicle to follow. Closed loop methods have a significant advantage over open loop methods in that they do not require a trial-and-error approach normally required by open loop methods to achieve the desired vehicle path. As a result, closed loop methods may result in significant time savings and associated user productivity. Historically, however, closed loop methods have had two drawbacks: First, they require user inputs that are non-intuitive and difficult to determine. Second, closed loop methods often have stability problems.

Due to the wide and ever increasing application of thermoplastic parts in the automotive industry, the measurement and interpretation of their properties must be thoroughly understood before anyone can hope to correctly utilize the results in material selection, product design, and performance analysis while all these can be greatly influenced by the end-use conditions. Tensile properties of thermoplastics, such as stress and strain at yield, ultimate tensile strength, and Young's modulus, are among the most widely measured and cited mechanical properties for material evaluation, quality control, structure design, modeling, and failure analysis. This paper deals with several major challenges that an engineer may face when attempting to obtain accurate tensile property data for thermoplastics. One such challenge is the trend of automotive industry today to convert from ASTM to ISO procedures for thermoplastics evaluation and product certification.

Markings or observable anomalies on seat belt webbing and hardware can be classified into two categories: (1) marks caused by collision forces, or “loading marks”; and (2) marks that are created by non-accident situations, or “noncollision marks”. In a previous work, a survey of the driver's seat belt of 307 vehicles that had never experienced a collision was conducted, and several examples of marks created by normal, everyday usage, or “normal usage marks” were presented. It was found that some normal usage marks were visually similar to loading marks. This paper presents several examples comparing loading marks to visually similar normal usage marks and discusses the important similarities and differences.

Java is a very popular programming language for Internet- based applications. With the increasing use of webbased technology in the automotive industry, Java has the potential to play a significant role in the future of large-scale 3-D computations such as crash analysis and aerodynamic modeling. This paper focuses on Java' s current bottlenecks for such applications and activities to overcome those limitations. Topics discussed include: current status of large-scale automotive computations; numeric performance comparisons of Java, C++, and FORTRAN; Java benchmarks to assess numerical performance; Java' s current floating-point limitations; a roadmap for Java evolution amongst the commercial automotive independent software vendors (ISVs).

Crash testing injury calculations have historically been based on measurements of forces and accelerations on cadavers subjected to crashes. For example, the Head Injury Criteria (HIC) was developed by bolting accelerometers to the skulls of cadavers and comparing the actual damage to the head and brain to the measured acceleration. These calculations are currently being improved by evaluating the injuries sustained by race car drivers involved in crashes during races. Biomechanics researchers have installed accelerometers to measure the race car accelerations during a crash. To further improve the injury assessment capabilities, the researchers would like to measure the actual acceleration of the driver’s head. Unfortunately race drivers, unlike cadavers, object to having accelerometers bolted to their skulls. Mounting accelerometers on the racing helmets gives some data, but the drivers head can move within the helmet during a crash.

To test the reliability of the SmartFire® ionization data as a parameter for detecting misfires, we fitted an inline-4 cylinder engine with in-cylinder pressure sensors and compared their data to that provided by ionization current sensing. The ignition circuitry was tested for its ability to recognize misfires, and for its potential to re-strike the ignition early enough in the cycle to provide smooth engine operation. Unique design features of the SmartFire ignition circuit enable the measurement of ion current as early as 300 microseconds after the initiation of the spark discharge, thereby allowing early detection of improper combustion. We compared the indicated mean effective pressure (IMEP) to the integrated ionization signal. When a misfire was measured by the IMEP, the integrated ion signal indicated the misfire as well. The ignition circuitry successfully identified the cycles with improper combustion.

Compatibility between cars is a major issue worldwide. In Europe several groups are dealing with it: BRITE EURAM, which involves the majority of European manufacturers, and EEVC WG15, involving several European test laboratories and institutes, are the most active in Europe at the moment. In the past also ADAC developed a similar study in Germany. In US NHTSA is conducting studies, mainly related to the particular American market, where pick-ups represent the most important cause of incompatibility. Several approaches and test procedures are proposed to assess compatibility which consider tests against fixed obstacles, like offset deformable barriers and full width barrier (to measure energy absorption and stiffness of the front end and its distribution) and overload tests (to measure resistance capability of the compartment).

A closed loop full-scale automotive climatic wind tunnel is described. The tunnel simulates wind and rain as well as several road conditions. It generates under controlled heat loading, wind speeds of up to 50kmh with different approach boundary conditions, rains from drizzle to cloudburst and road inclines up to 15° in any direction. The design and optimization process of the tunnel functions is outlined and examples of its use in vehicle development are given. The size constraint and the need for a compact design are important features of the tunnel. The tunnel provides an important test bed for close scrutiny of the relationship between rain ingress, vehicle speed, road condition, heat loading and vehicle geometry. The tunnel can also be used to study vehicle thermal management, vehicle thermal comfort, engine cold starting, and wipers efficiency in sever cold weather.

Orbital debris mitigation policy has become outdated, and corporations that have an interest in space commerce have historically underused it. This paper studies the policy aspect of orbital debris mitigation, focusing on debris originating from spent rocket stages and telecommunications satellites. The commercialization of space, in particular the Lower Earth Orbit (LEO) has increasingly drawn the interest of space flight and telecommunications industries. This paper shows how new standards, policies, and regulations could affect industrial practices related to orbital debris mitigation. The formation of new policies will have a significant impact on commercial space industries.

Accelerated testing techniques for cylinder head gaskets have become absolutely necessary because of developments at engine manufacturers including: shorter engine development times, high costs of vehicle and dynamometer testing, new material generations for engine components, and new engine generations and longer engine life This paper will describe two accelerated test methods for Multi-Layer Steel (MLS) cylinder head gaskets and will discuss the most important parameters which influence MLS cylinder head gasket functional performance. We will describe how these parameters have been duplicated in the laboratory using the accelerated tests: the Bending Simulator and the Hydraulic Pulsator. The test method results have been confirmed based on detailed metallurgical analysis of MLS gaskets; comparing field (dynamometer and vehicle) tested gaskets to those gaskets evaluated on accelerated tests.

As the competition between automotive manufacturers is becoming more and more fierce and simultaneously the customer's demands are substantially increasing, BMW Group has chosen to fundamentally reengineer their ‘Time to Market’ - as well as their ‘Time to Customer’ process.

A Multi-Axial Simulation Table (rig) has been installed to perform a durability test of the vehicle exhaust system under simulated excitation. As part of this ongoing project, a computational model of the rig was developed using a dynamic simulation package, ADAMS®. The process of model development is described and the results of a correlation study are presented in this paper. Critical features in the model development included a mainframe, main frame supporting arms, the engine and transmission assembly, and the transmission output shaft assembly. Additionally, to accurately perform the model analysis and correlation study, several in-house codes are developed for numerical analysis.

Given the myriad of testing options available and the reams of testing specifications that exist today, how do you know what testing process should be used for a given component or system? What information is needed and what is the most efficient means of getting the desired results. This paper compares two accelerated testing methods with more traditional validation tools and examines the relationship between the information goals, the process used, the anticipated failure modes, and the equipment needed. A decision making algorithm will be proposed.