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The performance of inflatable toepan padding for mitigating lower limb injuries was investigated. A rigid multi-body model was used to describe the scenario of an occupant in an automobile frontal crash with toepan intrusion. The emphasis was placed on the lower limb responses during impact. The interaction between the lower limbs and the inflatable toepan padding was described by the contact between the feet and the load distribution plate of the padding. Computational simulations were performed to analyze the effects of the controlled motion of this plate on the lower limb impact responses.

Investigations were made on computational analyses of ejection seat cushions, which include the characterization of the impact properties of ejection seat cushions, computational modeling of an ejection seat cushion system using a rigid multi-body dynamics program, parametric optimization of the cushion impact properties, and global sensitivity analysis of the safety performance of a cushion to its impact properties. The results indicate that computational analyses can be used to effectively evaluate and improve the cushion performance in the prevention and reduction of spinal injuries.

This paper presents efforts made on the computational modeling and simulation of out-of-position occupant-airbag interaction. The airbag was modeled using the finite element method with LSDYNA. Static airbag deployment tests were performed to support and validate computational modeling efforts. A 50-segment rigid body model was developed for the 5th percentile Hybrid-III female dummy using the Articulated Total Body (ATB) model program. This occupant model allows for the detailed simulation of occupant responses in several body regions. The system that describes out-of-position occupant-airbag interaction in frontal crashes, including airbag, occupant, and major vehicle structures, was modeled through the integration of the rigid body occupant model with the finite element airbag model using the function provided by LSDYNA. The biodynamics of the occupant-airbag interaction were simulated for unbelted occupant sled impacts and two out-of-position static deployment impacts.

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.

Computer simulations of occupant dynamics are ideal for conducting parametric studies evaluating injury countermeasures. A rollover accident was selected from the National Accident Sampling System (NASS) for simulation to validate the Articulated Total Body (ATB) model's capability to predict occupant dynamics during rollover accidents and to gain insight into injury mechanisms. Simulations of both the driver and passenger occupants which may be used in future countermeasure studies are performed. In the selected accident, a pickup truck rolled multiple times, the belted driver had minor injuries and the unrestrained passenger was ejected with fatal injuries. The body properties for both occupants were obtained using the Generator of Body Data (GEBOD) program based on their weights, heights, and sexes. The interior configuration of the vehicle compartment was modeled based on measurements taken from another vehicle of the same model.