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Computer simulation was used as a complement to crash and injury field data analysis and physical sled and barrier tests to investigate and predict the spinal injuries of a rear impact in an IndyCar. The model was expected to relate the spinal loads to the observed injuries, thereby predicting the probability and location of spinal fractures. The final goal is to help reduce the fracture risk by optimizing the seat and restraint system design and the driver's position using computer modeling and sled testing. MADYMO Full FE Human Body Model (HBM) was selected for use because of its full spinal structural details and its compatibility with the vehicle and restraint system models. However, the IndyCar application imposed unique challenges to the HBM. First, the driver position in a race car is very different from that in a typical passenger car.

A steering wheel is an indispensable component in an automobile. Although the steering wheel was invented about one hundred years ago and its structure has since become more and more complex with numerous innovations, documented analysis on steering wheel performance is very limited. Today, a steering wheel is not only a wheel that controls where your car goes; it also plays an important role in a vehicle occupant protection system. Therefore, many requirements have to be met before a steering wheel goes into production. With the development of computational mechanics and increasing computer capability, it has become much easier to evaluate the steering wheel performance in a totally different way. Instead of running prototype tests, steering wheel designs can be modeled virtually in various scenarios using finite element analysis, thus facilitating the development cycle.

The Curtain Airbag (CAB) is used currently to provide head and neck protection for the front-seat and rear-seat vehicle occupants during side-impact collisions and vehicle rollovers. The coated fabric materials are used in CABs for occupant protection in side impact and rollover events. In this paper the design and development study of CABs is described by using simulation and physical tests. The mechanical properties for the airbag material are determined by uniaxial test in the fill and warp directions. Shear strength is also evaluated by using the uniaxial test, but the specimen is cut along 45° angle. These test values are used in the finite element (FE) simulations. In this paper, a methodology of the design study is discussed. A Free Motion Headform (FMH) impacting a pole with a pillow shaped airbag is used in the design study. The influences of CAB design parameters such as pressure, chamber width, impact speed and hit location are evaluated.

Since its invention in early 1990s, the side curtain airbag has become an important part of the occupant restraint system for side impact and rollover protection. Computer Aided Engineering (CAE) is often used to help side curtain airbag design. Because of the unique characteristics of side curtain airbag systems, the simulation of side curtain airbag systems faces different challenges in comparison to the simulation of driver and passenger airbag systems. The typical side curtain airbag CAE analysis includes, but is not limited to, cushion volume evaluation, cushion coverage review, cushion shrinkage and tension force review, deployment timing review and seam shape and location review. The commonly used uniform pressure airbag models serve the purpose in most cases.

Computer modeling and simulation have become one of the primary methods for development and design of automobile occupant protection systems (OPS). To ensure the accuracy and reliability of a math-based OPS design, the correlation quality assessment of mathematical models is essential for program success. In a typical industrial approach, correlation quality is assessed by comparing chart characteristics and scored based on an engineer's modeling experience and judgment. However, due to the complexity of the OPS models and their responses, a systematic approach is needed for accuracy and consistency. In this paper, a correlation grading methodology for the OPS models is presented. The grading system evaluates a wide spectrum of a computer model's performances, including kinematics, dynamic responses, and dummy injury measurements. Statistical analysis is utilized to compare the time histories of the tested and simulated dynamic responses.

The complexity of automotive systems continues to rise. Consumers demand more and more features on their vehicles, including those that provide comfort, convenience, and safety. At the same time, the reliability of automobiles continues to improve. Today's automobile manufacturers are looking for suppliers that can provide increased feature content, and at the same time provide highly reliable, flawlessly executed systems. This paper will describe a systems engineering process that is employed at one automotive industry supplier. Borrowing a page from the aerospace industry, we'll describe a rigorous process and methodology for developing and documenting requirements, creating solutions to meet those requirements, and validating those solutions against the requirements. Several case studies will be described that demonstrate the benefits derived through the use of the process, its tools and its methodologies.

Sophisticated computer simulation of human response during various violent force exposure situations requires not only the validated programs, but also high quality databases, especially the data sets that characterize human body structures. Although anthropometric surveys and stereophotometric studies have been performed to create geometric and inertial property databases for the human body, there have been limited efforts on establishing the joint kinematics and resistive torque data sets. This paper presents the development, implementation, and validation of the human articulating joint model parameters for crash dynamics simulations. Measured human joint data on the voluntary range of motion and passive resistive torques were used to mathematically model the shoulder, elbow, hip, knee, and ankle joints.

The objective of this study was to mathematically model several proposed vehicle glazing materials using derived force-deflection characteristics, validate the models' dynamic behavior, and use the resulting glazing models in simulations of occupant dynamics during vehicle rollover. Simulations were performed with the three-dimensional, multibody dynamics program, the Articulated Total Body (ATB) model. The contact characteristics of side windows of tempered glass; polymethyl methacrylimide, also referred to as PMMI; and polycarbonate; as well as windshields from Ford Tempos and Jeeps, were developed from headform impact tests. These characteristics were first validated by performing simulations of the headform impact tests, and were then included in rollover simulations. Previously validated simulations of belted driver and unbelted passenger dynamics during an actual rollover accident were used as the baseline simulations.