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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 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.