Search Results

Lateral impacts have been shown to produce a large portion of both serious and fatal injuries within the total automotive crash problem. These injuries are produced as a result of the rapid changes in velocity that an automobile occupant's body experiences during a crash. In an effort to understand the mechanisms of these injuries, an experimental program using human surrogates (cadavers) was initiated. Initial impact velocity and compliance of the lateral impacting surface were the primary test features that were controlled, while age of the test specimen was varied to assess its influence on the injury outcome. Instrumentation consisted of 24 accelerometer channels on the subjects along with contact forces measured on the wall both at the thoracic and pelvic level. The individual responses and resulting injuries sustained by 11 new subjects tested at the University of Heidelberg are presented in detail.

A major focus of the National Highway Traffic Safety Administration's (NHTSA) vehicle compatibility and aggressivity research program is the development of a laboratory test procedure to evaluate compatibility. This paper is written to explain the associated goals, issues, and design considerations and to review the preliminary results from this ongoing research program. One of NHTSA's activities supporting the development of a test procedure involves investigating the use of an mobile deformable barrier (MDB) into vehicle test to evaluate both the self-protection (crashworthiness) and the partner-protection (compatibility) of the subject vehicle. For this development, the MDB is intended to represent the median or expected crash partner. This representiveness includes such vehicle characteristics as weight, size, and frontal stiffness. This paper presents distributions of vehicle measurements based on 1996 fleet registration data.

The National Highway Traffic Safety Administration (NHTSA) is conducting a research program to investigate the use of the 40 percent offset deformable barrier (ODB) crash test procedure to reduce death and injury, in particular debilitating lower extremity injuries in frontal offset collisions. This paper presents the results of 22 ODB crash tests conducted with 50th percentile male and 5th percentile female Hybrid III (HIII) dummies fitted with advanced lower legs, Thor-Lx/HIIIr and Thor-FLx/HIIIr, to assess the potential for debilitating and costly lower limb injuries. This paper also begins to investigate the implications that the ODB test procedure may have for fleet compatibility by evaluating the results from vehicle-to-vehicle crash tests.

The primary description of crash severity in most accident databases is vehicle delta-V. Delta-V has been traditionally estimated through accident reconstruction techniques using computer codes, e.g. Crash3 and WinSmash. Unfortunately, delta-V is notoriously difficult to estimate in many types of collisions including sideswipes, collisions with narrow objects, angled side impacts, and rollovers. Indeed, approximately 40% of all delta-V estimates for inspected vehicles in the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) 2001 are reported as unknown. The Event Data Recorders (EDRs), now being installed as standard equipment by several automakers, have the potential to provide an independent measurement of crash severity which avoids many of the difficulties of accident reconstruction techniques. This paper evaluates the feasibility of replacing delta-V estimates from accident reconstruction with the delta-V recorded by EDRs.

Rotational motion of the head as a mechanism for brain injury was proposed back in the 1940s. Since then a multitude of research studies by various institutions were conducted to confirm/reject this hypothesis. Most of the studies were conducted on animals and concluded that rotational kinematics experienced by the animal's head may cause axonal deformations large enough to induce their functional deficit. Other studies utilized physical and mathematical models of human and animal heads to derive brain injury criteria based on deformation/pressure histories computed from their models.

Little is known about the response of the shoulder complex due to lateral and oblique loading. Increasing this knowledge of shoulder response due to these types of loading could aid in improving the biofidelity of the shoulder mechanisms of anthropomorphic test devices (ATDs). The first objective of this study was to define force versus deflection corridors for the shoulder corresponding to both lateral and oblique loading. A second focus of the shoulder research was to study the differences in potential injury between oblique and lateral loading. These objectives were carried out by combining previously published lateral impact data from 24 tests along with 14 additional recently completed lateral and oblique tests. The newly completed tests utilized a pneumatic ram to impact the shoulder of approximately fiftieth percentile sized cadavers at the level of the glenohumeral joint with a constant speed of approximately 4.4 m/sec.

Rear seat adult occupant protection is receiving increased attention from the automotive safety community. Recent anthropomorphic test device (ATD) studies have suggested that it may be possible to improve kinematics and reduce injuries to rear seat occupants in frontal collisions by incorporating shoulder-belt force-limiting and pretensioning (FL+PT) technologies into rear seat 3-point belt restraints. This study seeks to further investigate the feasibility and potential kinematic benefits of a FL+PT rear seat, 3-point belt restraint system in a series of 48 kmh frontal impact sled tests (20 g, 80 ms sled acceleration pulse) performed with post mortem human surrogates (PMHS). Three PMHS were tested with a 3-point belt restraint with a progressive (two-stage) force limiting and pretensioning retractor in a sled buck representing the rear seat occupant environment of a 2004 mid-sized sedan.

This paper describes the National Highway Traffic Safety Administration's (NHTSA) efforts to determine how different outrigger designs can affect J-Turn and Road Edge Recovery test maneuver outcome. Data were collected during tests performed with three different outrigger designs (made from aluminum, carbon fiber, and titanium) having different physical properties (geometry and weight). Four sport utility vehicles were tested: a 2001 Chevrolet Blazer, 2001 Toyota 4Runner, 2001 Ford Escape, and a 1999 Mercedes ML320. The 4Runner and ML320 were each equipped with electronic stability control, however the systems were disabled for the tests performed in this study. A detailed description of the testing performed and the results obtained are discussed. From the results, a comparison of how the three outrigger designs affected the test results is provided.

Forty-two side impact cadaver sled tests were conducted at 24 and 32 km/h impact speeds into rigid and padded walls. The post-mortem human subjects were instrumented with accelerometers on the ribs and spine and chest bands around the thorax and abdomen to characterize their mechanical response during the impact. Load cells at the wall measured the impact force at the level of the thorax, abdomen, pelvis, and lower extremities. The resulting injuries were determined through detailed autopsy and radiography. Rib fractures with or without associated hemo/pneumo thorax or flail chest were the most common injury with severity ranging from AIS=0 to 5. Full and half thorax deflections were computed from the chest band data. The cadaver test data was analyzed using ANOVA and logistic regression. The age of the subject at the time of death had influence on injury outcome while gender and mass of the subject had little or no influence on injury outcome.