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There is little prior research into chain-collisions, despite their relatively large contribution to injury and harm in motor-vehicle collisions. This study conducted a series of rear-impact, front-impact, and chain-collision impacts using a bumper car ride at an active amusement park as a proxy for automobiles. The purpose was to begin to identify the threshold time range when separate, discrete collisions transition into a hybrid or combined chain-collision mode and provide bases for future analyses. The test series consisted of rear impacts into an occupied target vehicle from a driven bullet vehicle; frontal impacts into a perimeter barrier (wall); chain-collisions consisting of a driven bullet vehicle striking an occupied primary target vehicle, which then collided with a non-occupied secondary target vehicle; and chain-collisions consisting of a driven bullet vehicle striking an occupied primary target vehicle which then collided with a wall.

This study conducted a series of rear-impact, side-impact, barrier, and free-operation collisions using a bumper car ride at an active amusement park. Two conditions were studied: staged and free operation. Each staged test included a bullet (impacting) vehicle operated by a rider and a target (impacted) static vehicle or structure. Impact configurations of frontal collisions of the bullet vehicle into the rear and side of a target vehicle were consistent with the existing literature. The free operation condition involved collisions which were not pre-determined, and operators may not have been prepared for collision timing, magnitude, and direction. Results demonstrated high repeatability for vehicle parameters, such as impact velocity, change in velocity, and peak acceleration.

SAE J211 provides no definitive specification as to the appropriate procedures for filtering angular rate sensor data prior to differentiation into angular acceleration data, especially for impact data. Accordingly, a 3-2-2-2 array (nine-accelerometer-package or NAP) of linear accelerometers and a triaxial angular rate sensor were mounted into a Hybrid III 50th-percentile-male ATD headform and compared in a variety of impact events and multibody simulations. Appropriate low-pass digital filter cutoff frequencies for differentiating the angular rate sensor data into angular accelerations were sought via residual analysis in accordance with current SAE J211 guidelines.

Few studies have investigated pediatric head injury mechanics with subjects below the age of 8 years. This paper presents non-injurious head accelerations during various activities for young children (2 to 7 years old). Eight males and five females aged 2-7 years old were equipped with a head sensor package and head kinematics were measured while performing a series of playground-type activities. The maximum peak resultant accelerations were 29.5 G and 2745 rad/s2. The range of peak accelerations was 2.7 G to 29.5 G. The range of peak angular velocities was 4.2 rad/s to 22.4 rad/s. The range of peak angular accelerations was 174 rad/s2 to 2745 rad/s2. Mean peak resultant values across all participants and activities were 13.8 G (range 2.4 G to 13.8 G), 12.8 rad/s (range 4.0 rad/s to 12.8 rad/s), and 1375 rad/s2 (range 105 rad/s2 to 1375 rad/s2) for linear acceleration, angular velocity, and angular acceleration, respectively.

Low-speed collisions between tractor-semitrailers and passenger vehicles may result in large areas of visible damage to the passenger vehicle, but often produce limited damage to the tractor-semitrailer. Despite this, such accidents may lead to assertions of serious injury to the tractor driver and/or sleeper compartment occupant. Research regarding the impact environment and resulting injury potential of the occupants during these types of impacts is limited. This research investigated driver and sleeper compartment occupant responses to relatively low-speed and low-acceleration impact events. Five crash tests involving impact between a tractor-semitrailer and a passenger car were conducted. The test vehicles were a van semitrailer pulled by a tractor and three identical mid-sized sedans. The occupants of the tractor included a human driver and an un-instrumented Hybrid III 50th-percentile-male anthropomorphic test device (ATD).

Neck injury assessment reference values (IARVs) and tolerance values for children have been specified using animal data compared to the loading of anthropomorphic test devices (ATDs). However, there is a paucity of data regarding the neck loads generated during non-injurious situations for children. Six males and six females aged 8-11 years old were equipped with a validated head sensor package and upper neck loads and moments were calculated from measured head kinematics while performing a series of playground-type activities. The maximum forces were 686 N in compression, 177 N in tension, and 471 N in shear, the maximum moments were 18.2 N-m in flexion, 6.0 N-m in extension, 6.4 N-m in lateral bending, and 12.1 N-m in axial twist. Female subjects exhibited similar loads and moments to their male counterparts, but larger Nij values. The peak loads measured in this study are larger than or comparable to those undertaken with adult subjects participating in similar activities.

A 3-2-2-2 array of linear accelerometers and a combination of a triaxial linear accelerometer and a triaxial angular rate sensor were mounted into a Hybrid III 50th percentile male ATD head-form and compared in a variety of short- and long-duration events. An appropriate low-pass filter cutoff frequency for differentiating the angular rate sensor data into angular accelerations was found by using a residual analysis to find individual cutoff frequencies for the three center of mass (COM) linear accelerometer channels and the three angular rate sensor channels and taking the arithmetic mean of the six cutoffs. The angular rate sensors provide more accurate rotational rates than integrated angular accelerations calculated from arrays of linear accelerometers and are less cumbersome, especially for events lasting longer than 200 ms.

While adult head injuries have been studied over the past six decades, few studies have investigated pediatric head injury mechanics. This paper presents non-injurious head accelerations during various activities in a pediatric population. Six males and six females aged 8–11 years old were equipped with a validated head sensor package and head kinematics were measured while performing a series of playground-type activities. Maximum resultant values across all participants and activities were 25.7 g (range 3.0 g to 25.7 g), 16.0 rad/s (range 10.4 rad/s to 16.0 rad/s), and 1705 rad/s2 (range 520 rad/s2 to 1705 rad/s2) for linear acceleration, angular velocity, and angular acceleration, respectively. Mean maximum resultant values across all participants and activities were 9.7 g (range 2.1 g to 9.7 g) and 734 rad/s2 (range 188 rad/s2 to 734 rad/s2) for linear and angular acceleration, respectively.