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This paper reports the analytical procedure developed for a simulation of knee impact during a barrier crash using a hybrid III dummy lower torso. A finite element model of the instrument panel was generated. The dummy was seated in mid-seat position and was imparted an initial velocity so that the knee velocity at impact corresponded to the secondary impact velocity during a barrier crash. The procedure provided a reasonably accurate simulation of the dummy kinematics. This simulation can be used for understanding the knee bolster energy management system. The methodology developed has been used to simulate impact on knee for an occupant belted or unbelted in a frontal crash. The influence of the vehicle interior on both the dummy kinematics and the impact locations was incorporated into the model. No assumptions have been made for the knee impact locations, eliminating the need to assume knee velocity vectors.

Although there was a safety awareness from the earliest days of the automobile, systematic approaches to designing for safety became more widespread after 1950 when large numbers of vehicles came into use in both the United States and Europe, and governments in both continents undertook a widespread highway development. Industry response to safety objectives and also to government regulation has produced a large number of safety enhancing engineering developments, including radial tires, disc brakes, anti-lock brakes, improved vehicle lighting systems, better highway sign support poles, padded instrument panels, better windshield retention systems, collapsible hood structures, accident sensitive fuel pump shut-off valves, and other items. A significant development was the design of the energy absorbing front structures.

A microcomputer-based, multichannel data acquisition system has been developed to acquire high frequency transient information typified by, but not limited to, automotive vehicle crash test applications. The system, which has been designed to be mounted on the test vehicle during a vehicle crash, will accommodate up to 240 channels. Each channel is comprised of a stand-alone microcomputer, memory for data storage, signal conditioning for piezoresistive transducers, automatic calibration and zero offsets, and programmable gain amplifier. The microcomputer is based upon a Motorola 6801/68701 microcomputer. The paper describes the design, development, and data processing characteristics of the prototype system.

This paper focuses on the role and significance of linear momentum and kinetic energy in controlling air bags aboard vehicles. Among the results of the study are analytic and geometric models that characterize crash behavior and control algorithms that quantify crash severity and identify crash configurations. These results constitute an effective basis for crash-data design and air-bag control.

This paper describes the development of a new component test methodology concept for simulating NHTSA side impact, to evaluate the performance of door subsystems, trim panels and possible safety countermeasures (foam padding, side airbags, etc.). The concept was developed using MADYMO software and the model was validated with a DOT-SID dummy. Moreover, this method is not restricted to NHTSA side impact, but can be also be used for simulating the European procedure, with some modifications. This method uses a combination of HYGE and VIA decelerator to achieve the desired door velocity profile from onset of crash event until door-dummy separation, and also takes into account the various other factors such as the door/B pillar-dummy contact velocity, door compliance, shape of intruding side structure, seat-to-door interaction and initial door-dummy distance.

An estimate of the rate of attrition of passenger cars, needed to establish the service life expectancy of passenger cars, is of major interest whenever long range production plans are made, marketing strategies are developed, the total needs of vehicles on the roads are estimated, etc. Estimation of vehicle attrition is very complex, however, due to the lack of accurate data and the interaction of the parameters affecting attrition. In 1980 and 1985, similar studies of attrition [1,2] utilized vehicle registration data available as of July, 1979 and as of July, 1984. The object of this paper is to update the results of these papers, using the 1991 July registration data, available in May 1992. Within the scope of this paper the attrition rates of various passenger cars are compared and the effect of geographical location on the attrition rates and the change in attrition rates during the past twenty years are discussed.

Various algorithms such as a direct computation approach, maximization requirement criteria method established by Chou and Nyquist, and a partitioning technique, for computing HIC are reviewed in this paper. An evaluation has been conducted considering both the accuracy and efficiency of these algorithms using theoretical pulses and experimental resultant head accelerations of a dummy obtained from the literature, Hyge sled and frontal barrier impact tests. Using results obtained from direct computations as “exact” values for comparison, all the algorithms evaluated provide HIC estimates in close agreement with the “exact” values. The CPU times, which are used as a measure for the assessment of computational efficiency, vary from algorithm to algorithm. Methods using a partitioning logic developed by Mentzer and a faster algorithm developed by Holstein and Alem are found to be very efficient, and are recommended for use in the computation of HIC.

In vehicle crash tests, an unbelted occupant's kinetic energy is absorbed by the restraints such as an air bag and/or knee bolster and by the vehicle structure during occupant ride-down with the deforming structure. Both the restraint energy absorbed by the restraints and the ride-down energy absorbed by the structure through restraint coupling were studied in time and displacement domains using crash test data and a simple vehicle-occupant model. Using the vehicle and occupant accelerometers and/or load cell data from the 31 mph barrier crash tests, the restraint and ride-down energy components were computed for the lower extremity, such as the femur, for the light truck and passenger car respectively.

A theoretical math model was created to assess the net effect of aging populations versus evolving system designs from the standpoint of thoracic injury potential. The model was used to project the next twenty-five years of thoracic injuries in Canada. The choice of Canada was topical because rulemaking for CMVSS 208 has been proposed recently. The study was limited to properly-belted, front-outboard, adult occupants in 11-1 o'clock frontal crashes. Moreover, only AIS3+thoracic injury potential was considered. The research consisted of four steps. First, sub-models were developed and integrated. The sub-models were made for numerous real-world effects including population growth, crash involvement, fleet penetration of various systems (via system introduction, vehicle production, and vehicle attrition), and attendant injury risk estimation. Second, existing NASS data were used to estimate the number of AIS3+ chest-injured drivers in Canada in 2001.

This paper contains a technical description of the Ford Motor Co.'s ACT system which has been designed to meet transportation needs in a wide variety of urban applications. The discussion covers the systems design features and operation of the driverless rubber-tired vehicles, the guideway, and the system's ability to meet expanding needs by a modular approach to the command and control design. Descriptions of Ford's new Cherry Hill Test Track and the first installations at the Fairlane Town Center in Dearborn, Mich., and the Bradley International Airport, Hartford, Conn., are also presented.

Powertrain mounts are one of the important design characteristics of a vehicle. Powertrain is mostly mounted to the front subframe and once installed in a vehicle, powertrain mounting has an important role in determining the vehicle vibration characteristics. A good mounting system isolates engine input vibration from the vehicle body and minimizes the effect of road inputs to the customer. This paper discusses results of several dynamic models as they relate to noise, vibration and harshness (NVH) and compares the accuracy of these models. Various powertrain models are studied and their accuracy in comparison with full a vehicle model is discussed.

This paper outlines an approach to highway transportation research which considers the interrelationship of the major subsystems. It describes the framework, the variables, surveillance techniques, and new vehicle instrumentation. A model is described which serves as the basis for field testing and subsequent mathematical analyses. Surveillance systems including instrumented vehicles, ground, aerial, and space platforms are required as components of a real-time system. A research project, designed to evaluate driver stress, is discussed and sample computer data are shown.

The viscous criterion (V*C) has been proposed by biomechanics researchers as a generic biomechanical index for potential soft tissue injury. It is defined by the product of the velocity of deformation and the instantaneous compression of torso and abdomen. This criterion requires calculation and differentiation of measured torso/abdomen compression data. Various computational algorithms for calculating viscous criterion are reviewed and evaluated in this paper. These include methods developed by Wayne State University (WSU), NHTSA (DOT) and Ford. An evaluation has been conducted considering the accuracy of these algorithms with both theoretical and experimental data from dummy rib compressions obtained during a crash test. Based on these results, it is found that: V*C results depend on the scheme used in the computation process, the sampling rate and filtering of original raw data. The NHTSA method yields the lowest V*C value.

The SAE Large Male and Small Female Dummy Task Group has recommended a change to the Hybrid III dummy hip joint. This change was made because of a non-biofidelic interference in the current design that can influence chest accelerations. The modifications include a new femur casting shaft design and the addition of an elastomeric stop to the top of the casting. Static testing and Hyge sled tests were done to evaluate the modifications. Based on the results, the new design satisfied the requirements set by the SAE task group and reduced the influence of hip joint characteristics on chest accelerations.

The design requirements for the frame as a load carrying member are discussed in relationship to a highway truck and its basic vehicle package. The theoretical and experimental procedures are given in detail to demonstrate the techniques for frame design. The features of a method to laboratory test a frame with correlation to service miles is discussed.

A need exists for a reliable and economical analytical aid for designing vehicle structures for controlled crash energy management. Several of the crash simulation methods, currently available to the designer in the evaluation and development of vehicle structures for crash, are reviewed with respect to their capabilities and shortcomings as design aids. An analytical technique is presented, structured along the lines of a design aid and based on a finite element beam model concept. The functions of the various elements of the code are discussed in the context of typical crash events one needs to consider in the design of a structure composed of beam- and column-type elements. The heart of the proposed system code VRUSH is a component code SECOLLAPSE which monitors and predicts crush responses of thin wall structural components and which controls the input into the system code. Also presented are models generated by SECOIXAPSE for typical loading cases.

After establishing the performance requirements and initial design assumptions, CAE concept models are used to set targets for major structural components to achieve desirable crash performance. When the designs of these major components become available they are analyzed in detail using nonlinear crash finite element models to evaluate their performance. All these components are assembled together later in a full car model to predict the overall vehicle crash performance. If the analysis shows that the targets are met, the design drawings are released for prototype fabrication. When CAE tools are effectively used, it will reduce product development cycle time and the number of prototypes. Crash analysis methodology has been validated and applied for steel automotive product development. Recently, aluminum is replacing steel for lighter and more fuel efficient automobiles. In general aluminum has quite different performance from steel, in particular with lower ductility.

The object of this paper is to develop a random vibration laboratory test specification for automotive subsystems using the Power Spectral Density (PSD) method. This development is based on the 150k mile field data collected from vehicle proving grounds. The simulated vibration bench test will be used to simulate the energy of the 150k mile field data. The developed specification will include 3 axis random vibration profiles of appropriate duration. The Power Spectral Density method converts the time-domain field data into the frequency-domain data. The Enveloped Energy method groups the similar road PSD profiles to produce a generic PSD profile. The Inverse Law allocates an adjusted duration to the desired PSD energy level. The Road Test Specification provides the duration time for the developed bench test. The n-Soft tool [1] is utilized for data reduction analysis. The Bench Test Specification of the Fuel subsystem is a pilot for this development.

Nowadays is a common sense the importance of the CAE usage in the modern automotive industry. The ability to predict the design behavior of a project represents a competitive advantage. However, some CAE models have become so complex and detailed that, in some cases, one just can not build up the model without a considerable amount of information. In that case simplified models play an important role in the design phase, especially in pre-program stages. This work intends to build an archetypal vehicle dynamics model able to predict the rollover resistance of a vehicle design. Through the study of a more complex model, carried out in Adams environment, it was possible to identify the key degrees of freedom to be considered in the simplified model along with important elements of the suspension which are also important design factors.

While testing vehicles for crash, particularly the offset frontal crash mode, new devices and techniques are needed to enhance the ability to measure rotations of certain vehicle components and dummy parts (or joints). The reason for this new demand is that the capabilities of existing techniques or devices in measuring rotations of small masses in confined areas are limited. Examples of the desired measurements are the rotations of dummy's feet and tibias as well as the rotations of the vehicle's toe-board during intrusion. These measurements help to understand dummy's ankle loads as a result of different intrusion rates. Furthermore, having these measurements is very beneficial to the validation of the computer models used in simulating the behavior of dummy's lower extremities in high intrusion crashes. Recent research demonstrated the use of an angular rate sensor, based on magnetohydrodynamic principles, on Hybrid-III dummies and cadavers.