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The passive safety performance of a child seat is modulated by the design features of the child seat and the vehicle interior. For example, in the rear-facing configuration, the child seat impacting front structures increases the head injury risk during a frontal crash. Therefore, this study evaluates the effectiveness of the load leg countermeasure in improving the child seat's overall kinematics and its capability to prevent the secondary impact on the vehicle interior structure in a severe frontal crash scenario. An in-depth, real-world crash investigation involving a properly installed rear-facing child seat impacting the center console was selected for the study where the infant sustained a severe brain injury. In addition, this crash is employed to choose the crash parameters for evaluating the effectiveness of the load leg countermeasure in a similar scenario.

Seatback and head restraints are the primary restraining devices in rear-impact collisions. The seatback failures expose front seat occupants to dive deep into the rear compartment survival space. Furthermore, it allows the occupants to get in a position with lower spinal tolerance to the impact direction. This paper employs sled tests to demonstrate the dangers of seatback failures in severe rear impact by allowing the occupants to orient their spine in its lowest tolerance zone to the impact direction. Furthermore, the sled test shows the potential of head pocketing phenomena and torso augmentation producing compressive cervical spine loading enough to cause first-order neck buckling. Finally, the results of collapsing seatback dynamics are compared to the strong seatback performance by conducting a similar test with a strong ABTS seatback.

Child crash injury protection in severe rear impact chiefly depends on how well the rear survival space bounded by the vehicle structure is maintained. Previous research and studies have shown the ill effects of front seatback collapse intruding into the rear child survival space from front with minor or no intrusions from the rear. This paper shows the child injury pattern and fatal injury mechanism for a rear impact crash with a severe compartment intrusion from the rear without any front seat occupant. Furthermore, it compares the injury outcome with a similar crash and severe intrusion in the presence of the front occupant employing a full-scale vehicle-to-vehicle crash test. A detailed real-world crash investigation is conducted to identify the injury mechanism and is compared with the outcome of similar severity rear impact vehicle-to-vehicle crash tests producing different injury patterns.

Child safety in the back seat during a rear-impact chiefly depends on how well the survival space is maintained at their location. Collapsing front seatback pose a foreseeable hazard as it intrudes into the survival space of the child on the backseat. Furthermore, the condition gets worse in the presence of a structural intrusion from the rear that tends to push the occupant further closer to the backward collapsing seatbacks. This paper reports two real-world rear impact collisions resulting severe to fatal injuries to the child occupant seating behind the driver. Each collision shows the dangers of seatback collapse into the survival space of the child. Furthermore, the paper demonstrates safety through design concept by employing seats with strong seatback design resisting collapse into the survival space of the child.

Prevention of passenger ejection from motor coach seats in the case of rollover and frontal crashes is critical for minimizing fatalities and injuries. This paper proposes a novel concept of affordably retrofitting 3-point seatbelts to protect passengers during these significant crash scenarios. Currently, the available options involve replacement of either the entire fleet, which takes time to avoid extremely high costs, or all seats with new seats that have seatbelts which is still expensive. Alternatively, this paper presents the development of an innovative product that can be installed in seat belt-ready bus structures at a fraction of the cost. The efficacy of the design is studied using finite element analysis (FEA) to meet Federal Motor Vehicle Safety Standards (FMVSS) 210 standards for conditions involved in frontal and side impacts.

The seatbelt is the primary restraint device that increases the level of occupant protection in a frontal crash. The belt performance is enhanced by the supplemental restraint provided by the airbag; seat and knee bolster working in combination with this primary restraining device. Small occupants are vulnerable to upper neck injuries when seated very close to the steering wheel. A lot of research and data availability for this situation ultimately led to the development of countermeasures capable of reducing upper neck loading. However, no data or research is available on the lower neck dynamic response of a small occupant primarily a 5th percentile female seated away from the steering wheel. MADYMO (Mathematical Dynamic Modeling), a biodynamic code is employed to validate a standard NHTSA (National Highway Traffic Safety Administration) frontal impact rigid barrier test with a 5th percentile ATD (Anthropomorphic Test Device) in the driver position.

Occupant motion in a vehicle rollover accident is a function of many factors. Some important ones are vehicle kinematics, position of the occupant in the vehicle, occupant size, ground topology and restraint usage. The far side belted occupants are more vulnerable than the near side occupants in a rollover accident as they have more energy as a result of their trailing and higher side of the vehicle. This outcome is attributable to the inadequate safety performance of the conventional single loop; B-pillar mounted D-ring restraints. Roof crush tends to displace the vehicle's B-pillar, resulting in D-Ring displacement which causes slack in the lap portion of the restraint. This slack enables centrifugal loads to move the far side occupant further away from the vehicle's instantaneous point of rotation. In this scenario, the presence of any ejection portal can result in an occupant becoming partially or fully ejected.

The necessity of avoiding the destructive and non-repeatable FSST (Full Scale Sled Test) makes it desirable to devise a cheaper and more repeatable method which can supplant this test procedure. This need developed the HCTD (HIC Component Testing Device) which is capable of providing conservative HIC results with higher repeatability. The computational model of the HCTD is validated against one of the tests conducted at CAMI with polyethylene foam. This validated model is used to conduct a series of tests with input parameters similar to the sled test to develop the correlation between the sled test and HCTD. This study hence concludes that a validated computational model of HCTD can be successfully utilized to address the HIC compliance issues for a foam padded surface.

The occupant retention performance of laminated and tempered side glazing during rollover collisions is analyzed. A brief history of automotive glazing is given, including a discussion of current technology. A summary of glazing failure mechanisms is provided, along with the results of impact and quasi-static pushout testing of undamaged commercial and prototype door windows. The investigation shows that supported laminated side glazing gives performance comparable to windshield glazing and can effect both primary and secondary containment of occupants. Results of documented unplanned rollover collisions and staged rollover tests are presented in support of the conclusions drawn.