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This paper presents the results of biomechanical testing of the SID-IIs beta+-prototype dummy by the Occupant Safety Research Partnership. The purpose of this testing was to evaluate the dummy against its previously established biomechanical response corridors for its critical body regions. The response corridors were scaled from the 50th percentile adult male corridors defined in International Standards Organization Technical Report 9790 to corridors for a 5th percentile adult female, using established International Standards Organization procedures. Tests were performed for the head, neck, shoulder, thorax, abdomen and pelvis regions of the dummy. Testing included drop tests, pendulum impacts and sled tests. The biofidelity of the SID-IIs beta+-prototype was calculated using a weighted biomechanical test response procedure developed by the International Standards Organization.

An objective, biomechanically based assessment is made of the risks of life-threatening brain injury of frontal crash test results. Published 15 ms HIC values for driver and right front passenger dummies of frontal barrier crash tests conducted by Transport Canada and NHTSA are analyzed using the brain injury risk curve of Prasad and Mertz. Ninety-four percent of the occupants involved in the 30 mph, frontal barrier compliance tests had risks of life-threatening brain injury less than 5 percent. Only 3 percent had risks greater than 16 percent which corresponds to 15 ms HIC > 1000. For belt restrained occupants without head contact with the interior, the risks of life-threatening brain injury were less than 2 percent. In contrast, for the more severe NCAP test condition, 27 percent of the drivers and 21 percent of the passengers had life-threatening brain injury risks greater than 16 percent.

The dilemma of using a shoulder belt force limiter with a 3-point belt system is selecting a limit load that will balance the reduced risk of significant thoracic injury due to the shoulder belt loading of the chest against the increased risk of significant head injury due to the greater upper torso motion allowed by the shoulder belt load limiter. However, with the use of air bags, this dilemma is more manageable since it only occurs for non-deploy accidents where the risk of significant head injury is low even for the unbelted occupant. A study was done using a validated occupant dynamics model of the Hybrid III dummy to investigate the effects that a prescribed set of shoulder belt force limits had on head and thoracic responses for 48 and 56 km/h barrier simulations with driver air bag deployment and for threshold crash severity simulations with no air bag deployment.

A professional high diver, instrumented with accelerometers, performed sixteen dives from heights between 27-57 ft. For each dive, he executed a 3/4 turn and landed supine on a 3-ft deep mattress which consisted of pieces of low-density urethane foam encased in a nylon cover. Using FM telemetry, sagittal plane decelerations were recorded for a point either on the sternum or the forehead. Impact velocities and corresponding stopping distances for the thorax and the head were calculated from high-speed movies of the dives. For a 57-ft dive, the impact velocity of the thorax was 41 mph with a corresponding stopping distance of 34.6 in. The peak resultant deceleration of the thorax was 49.2 g with a pulse duration of 100 ms. The maximum rate of change of the deceleration of the thorax was 5900 g/s. No discomfort was experienced as a result of this impact. The maximum forehead deceleration occurred during a 47.0-ft drop and exceeded 56 g with a Gadd Severity Index greater than 465.

Two Highway Safety Research Institute (HSRI) dummies were tested and evaluated. Based on the analysis given, the HSI dummy should not be used for vehicle qualification testing. However, many of its components offer viable alternatives for future dummy development. The dummy was found to have inadequate biomechanical fidelity in the head, neck, and chest, although its characteristics were very promising and, as a whole, biomechanically superior to the Hybrid II. Its repeatability and reproducibility in dynamic component tests were better than the Hybrid II dummy. In particular, the HSRI friction joints were outstanding in repeatability and had a significant advantage in usability in that they do not require resetting between tests. In three-point harness and ACRS systems tests, the values of injury criteria produced by the HSRI dummy were generally lower than those obtained with the Hybrid II, especially the femur loads in the ACRS tests.

Details of a new crash simulator and preliminary results from a series of cadaver knee impact experiments were presented at the Eighth Stapp Conference. During the past year additional data concerning injury to the knee-thigh-hip complex have been obtained, and the studies have been extended to consider impact to the chest. Results to date indicate that for knee impacts against a moderately padded surface it is not possible to predict whether failure of the patella, femur or pelvis will occur first, although in these studies femoral fractures occurred most frequently. A force of 1400 lb. is recommended at this time as a reasonably conservative value for the over-all injury threshold level. Volunteers tolerated impact loads to the knee of 800-1000 lb. For loads applied over the sternum through a 25-30 padded surface, static and dynamic thoracic stiffness characteristics were determined for a limited number of cadavers.

A review and analysis of existing cadaver head impact data has been conducted in this paper. The association of the Head Injury Criterion with experimental cadaver skull fracture and brain damage has been investigated, and risk curves of HIC versus skull fracture and brain damage have been developed. Limitation of the search for the maximum HIC duration to 15ms has been recommended for the proper use of HIC in the automotive crash environment.

Side impact tests were conducted on the EUROSID and SID to assess their biofidelity compared to the response requirements of the international Standards Organization. The body regions evaluated were the head, neck, thorax, shoulder, abdomen, and pelvis. Test conditions and data normalization procedures are outlined in the report. Data plots are given which compare the impact response of each dummy to the ISO requirements. The EUROSID gave humanlike responses for most tests involving padded surface impacts, but its responses were not humanlike for rigid surface impacts. Overall, the EUROSID responses were more humanlike than the responses of the SID.

An evaluation of the four injury risk curves proposed in the NHTSA NCAP for estimating the risk of AIS≻=3 injuries to the head, neck, chest and AIS≻=2 injury to the Knee-Thigh-Hip (KTH) complex has been conducted. The predicted injury risk to the four body regions based on driver dummy responses in over 300 frontal NCAP tests were compared against those to drivers involved in real-world crashes of similar severity as represented in the NASS. The results of the study show that the predicted injury risks to the head and chest were slightly below those in NASS, and the predicted risk for the knee-thigh-hip complex was substantially below that observed in the NASS. The predicted risk for the neck by the Nij curve was greater than the observed risk in NASS by an order of magnitude due to the Nij risk curve predicting a non-zero risk when Nij = 0. An alternative and published Nte risk curve produced a risk estimate consistent with the NASS estimate of neck injury.

Child head trauma in the United States is responsible for 30% of all childhood injury deaths with costs estimated at $10 billion per year. The common tools for studying this problem are the child anthropomorphic test devices (ATDs). The headform sizes and structural properties of child ATDs are based on various anthropometric studies and scaled Hybrid III mass and center of gravity (CG) properties. The goals of this study were to produce pediatric head and skull contours, provide estimates of pediatric head mass, mass moment of inertia and CG locations, and compare the head contours with the current child ATD head designs. To that end, computer tomography (CT) scans from one hundred eighty-five children in twelve age groups were analyzed to develop three-dimensional head and skull contours. The contours were averaged to estimate head and skull contours for children aged 1 month to 10 years. Inertial properties were estimated from a small sample of post-mortem human subjects (PMHSs).

The Human Mechanical Simulation Subcommittee of the Human Biomechanics and Simulation Standards Committee of the Society of Automotive Engineers took on the task of defining test procedures and associated response guidelines to be used to assess the level of biofidelity of side impact dummies that are being developed. This paper describes the results of their efforts. Guidelines are provided for assessing the levels of biofidelity of dummies that represent 6-, 12-, and 18-month-old infants, 3-, 6-, and 10-year-old children, and of dummies that represent a small female, midsize male and large male adults. These guidelines were developed by normalizing the side impact biofidelity guidelines that were established by the International Standards Organization for the head, neck, shoulder, thorax, abdomen and pelvis of the midsize adult male.