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A 32-week pregnant 5th percentile female occupant model was developed. The uterus with fetus, amniotic fluid, placenta, fat, and ligaments, etc. was modeled by finite element methods, and it was integrated into MADYMO facet 5th percentile female occupant model. The model was validated via abdominal response corridors under belt loading and bar loading. It was used to study the strain of the uterine wall where the placental is contacted during car crash accidents, for the placental abruption is one of the major risks to the fetus. The simulation results show that the traditional 3-pt belt may not provide good protection for the fetus due to large strain can be found during car crash. So, two kinds of new belts were presented. They use different kinds of sheets to enwrap the protuberant abdomen of the pregnant female occupant in order to decrease the movement of the uterus relatively to the body. Thus, the strain of the uterine wall can be decreased significantly.

Statistic analysis on commercial vehicle crash accidents in China were done by using the annual traffic accident reports from Ministry of Public Security. The Chinese crash safety rules on commercial vehicle were introduced. The main reasons which cause severe injury to the passenger in the cab in frontal crash accidents were studied. HYPERMESH software was used to do the finite element modelling of the frontal structure and cab of a production truck. The swing hammer impact simulation was conducted by using LS-DYNA software and the results were compared with the test results to validate the model. A new supporting structure for the cab to improve the safety of the passenger in cab was proposed. Meanwhile, an extendable and retractable longitudinal beam energy absorbing structure was also studied by using the finite element model. The simulation results show that these structures can obviously improve the frontal crash safety of the commercial vehicle.

The S-beam of sports utility vehicles (SUV's) plays a key role in their frontal crashworthiness performance. To study the deformation patterns of the S-beam, a finite element model of a production SUV was developed and validated. Both experimental and simulation results show that large downward and inward deformation occurred at the S-beam in frontal crash. In order to control the deformation of the S-beam, two structural improvement methods were proposed. Computational simulation and tests were conducted to study their effectiveness. Results show that both of these improved methods can control the deformation of the S-beam effectively. The second design was then adapted to manufacture two SUV's for frontal and 40% offset frontal crashes. Experiments showed that the new S-beam design resulted in improvement in structural performance in full frontal crash as well as 40% offset crash modes.

The traditional deterministic optimal design is mostly based on meeting regulatory requirements specified in impact standards, without taking the randomness of the impact velocity and angle at the real world situation into consideration. This often leads to the optimization results that converge to the boundary constraints, thus cannot meet the reliability requirements of the product design. Structure members of B-pillar (e.g. inner panel, outer panel, and the reinforcing plate) play a major role in the side impact safety performance. This paper dealt with optimization of B-pillar by considering its dimensions and materials as the design variables, and the impact velocity and angle from real-world traffic accident conditions as the random variable inputs. Using a combination of design of experiment, response surface models, reliability theory and the reliability of design optimization method, a B-pillar was constructed based on the product quality engineering.

Child Restraint Systems (CRS), when used properly, can effectively avoid or reduce injury for children in motor vehicle crashes. To deal with the problems of the high rate of misuse of the CRS and submarining in frontal crashes when child occupants using traditional vehicle seat belts, a novel integrated child safety seat (ICSS) with a four-point seat belt and a ring-shaped lap belt was developed in this study. It is easy to operate and has lower rate of misuse. To study the protection performance of the newly developed ICSS in frontal crashes, a sled test and a series of simulations were conducted. The frontal impact sled test was conducted according to the European regulation ECE R44, which includes a Q6 anthropomorphic test device (ATD) and the impact velocity is 50 km/h. The simulation model included the ICSS model and the Q6 ATD model was developed in the MADYMO software, and the simulation model was validated by the sled test.

The research question investigated in this study is what are the key attributes of foot and ankle injury in the between-rail frontal crash? For the foot and ankle, what was the type of interior surface contacted and the type of resulting trauma? The method was to study with in-depth case reviews of NASS-CDS cases where a driver suffered an AIS=2 foot or ankle injury in between-rail crashes. Cases were limited to belted occupants in vehicles equipped with air bags. The reviews concentrated on coded and non-coded data, identifying especially those factors contributing to the injuries of the driver's foot/ankle. This study examines real-world crash data between the years 1997-2009 with a focus on frontal crashes involving 1997 and later model year vehicles. The raw data count for between-rail crashes was 732, corresponding to 227,305 weighted, tow-away crashes.

Previously, a 10-year-old (YO) pediatric thorax finite element model (FEM) was developed and verified against child chest stiffness data measured from clinical cardiopulmonary resuscitation (CPR). However, the CPR experiments were performed at relatively low speeds, with a maximum loading rate of 250 mm/s. Studies showed that the biomechanical responses of human thorax exhibited rate sensitive characteristics. As such, the studies of dynamic responses of the pediatric thorax FEM are needed. Experimental pediatric cadaver data in frontal pendulum impacts and diagonal belt dynamic loading tests were used for dynamic validation. Thoracic force-deflection curves between test and simulation were compared. Strains predicted by the FEM and the injuries observed in the cadaver tests were also compared for injury assessment and analysis. This study helped to further improve the 10 YO pediatric thorax FEM.

In order to provide an improved countermeasure for occupant protection, a new type of active reversible preload seatbelt (ARPS) is presented in this paper. The ARPS is capable of protecting occupants by reducing injuries during frontal collisions. ARPS retracts seatbelt webbing by activating an electric motor attached to the seatbelt retractor. FCW (Forward Collision Warning) and LDW (Lane Departure Warning) provide signals as a trigger to activate the electric motor to retract the seatbelt webbing, thus making the occupant restraint system work more effectively in a crash. It also helps reduce occupant’s forward movement during impact process via braking. Four important factors such as preload force, preload velocity and the length and timing of webbing retraction play influential roles in performance of the ARPS. This paper focuses on studying preload performance of ARPS under various test conditions to investigate effects of the aforementioned factors.