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This is the complete manuscript and replacement for SAE paper 2014-01-0482, which has been retracted due to incomplete content. This paper reports on 76 quasi-static tests conducted to investigate the behavior of road vehicle bumper systems. The tests are a quasi-static replication of real world low speed collisions. The tests represented front to rear impacts between various vehicles. Force and deflection were captured in order to quantify the stiffness characteristics of the bumper-to-bumper system. A specialized test apparatus was constructed to position and load bumper systems into each other. The purpose was to replicate or exceed damage that occurred in actual collisions. The fixture is capable of positioning the bumpers in various orientations and generates forces up to 50 kips. Various bumper-to-bumper alignments were tested including full overlap, lateral offset, and override/underride configurations.

There are exposures of the body to accelerations in the lumbar and thoracic regions on a regular basis with everyday activities and exercises. The purpose of this study was to evaluate the response of the thoracic and lumbar regions in human volunteers subjected to vigorous activities. A total of 181 tests include twenty volunteers subjected to four test scenarios: “plopping” down in a seat, a vertical jump, a vertical drop while in a supine position, and a vertical drop while seated upright in a swing. Each of the latter three activities included three severity levels with drop heights ranging from 25 mm to 900 mm. Volunteers selected represent the anthropometry of the general population including males and females at a wide range of weights (54 to 99 kg), heights (150 to 191 cm), and ages (26 to 58 years old). Instrumentation for each volunteer included tri-axial accelerometers attached to custom-fit mounts that were secured around the lumbar and upper thoracic regions.

It has been proposed that low speed collisions in which the damage is isolated to the bumper systems can be reconstructed using data from customized quasistatic testing of the bumper systems of the involved vehicles. In this study, 10 quasistatic bumper tests were conducted on 7 vehicle pairs involved in front-to-rear collisions. The data from the quasistatic bumper tests were used to predict peak bumper force, vehicle accelerations, velocity changes, dynamic combined crush, restitution, and crash pulse time for a given impact velocity. These predictions were compared to the results measured by vehicle accelerometers in 12 dynamic crash tests at impact velocities of 2 - 10 mph. The average differences between the predictions using the quasistatic bumper data and the dynamic crash test accelerometer data were within 5% for bumper force, peak acceleration, and velocity change, indicating that the quasistatic bumper testing method had no systematic bias compared to dynamic crash testing.