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Test methods for vehicle safety development are either based on the movement of a vehicle into a stationary barrier or the movement of a barrier into a stationary vehicle. When deemed necessary, a two-moving-vehicle impact is approximated by modifying the impact motion between the moving and stationary objects. For example, the Federal Motor Vehicle Safety Standard (FMVSS) 214 side-impact crash test procedure [1] approximates the lateral impact of a moving vehicle into the side of another moving vehicle by using a moving barrier with wheels crabbed so that the velocity vector of the barrier is not collinear with its longitudinal axis. Such approximations are valid when the post-impact motions of the two vehicles are not to be evaluated. Similarly, the published data indicates that historic analyses of motorcycle accidents and the advancements in motorcycle safety designs have been based, in large part, on single-moving-vehicle crash tests.

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).

There has been little published research into simulating two-moving motorcycle-to-car collisions for the purpose of accident reconstruction. In this paper a series of two-moving crash tests were conducted to study collisions of this type. These tests used a range of speeds for the cars and the motorcycles involved, with perpendicular and oblique intersection collision impact configurations. The tests were then simulated with two popular crash simulation packages which were not designed to simulate motorcycles. The purpose of this study was to evaluate existing techniques and develop new techniques for simulating motorcycles in these software packages and then to examine the ability of each package to simulate a two-moving motorcycle-to-car crash. The results demonstrate that it is indeed possible to simulate a motorcycle in these packages and that both packages can simulate two-moving motorcycle-to-car crashes reasonably well.

Low-speed sideswipe collisions between tractor-semitrailers and passenger vehicles can result in large movements and extensive areas of visible damage to the passenger vehicle. However, depending on the specifics of the collision, the resulting crash pulse may be extended, and the vehicle accelerations correspondingly low. Research regarding the impact environment and resulting injury potential of the occupants during these types of impacts is limited. Five full-scale crash tests utilizing a tractor-semitrailer and a passenger car were conducted to explore vehicle responses during these types of collisions for both the passenger car and the tractor-trailer. The test vehicles included a loaded van semitrailer pulled by a tractor and three identical mid-sized sedans. Instrumentation on the sedans included accelerometers and rotational rate sensors, and the vehicle and occupant kinematics were recorded using onboard and off-board real-time and high-speed video cameras.

Low-speed sideswipe collisions between tractor-semitrailers and passenger vehicles may result in large areas of visible damage to the passenger vehicle. However, due to the extended contact that occurs during these impacts, it is typical in these incidents for the crash pulse duration to be long and the vehicle accelerations to be correspondingly low. Research regarding the impact environment and resulting injury potential of the occupants during these types of impacts is limited. Five full-scale crash tests utilizing a tractor-semitrailer and a passenger car were conducted to explore the occupant responses during these types of collisions. The test vehicles included a van semitrailer pulled by a tractor and three identical mid-sized sedans. The occupants of the sedans included an instrumented Hybrid III 5th -percentile-male anthropomorphic test device (ATD) in the driver's seat and an un-instrumented Hybrid III 5th -percentile-female ATD in the left rear seat.

Far-side occupants are not addressed in current government regulations around the world even though they account for up to 40% of occupant HARM in side impact crashes. Consequently, there are very few crash tests with far-side dummies available to researchers. Sled tests are frequently used to replicate the dynamic conditions of a full-scale crash test in a controlled setting. However, in far-side crashes the complexity of the occupant kinematics is increased by the longer duration of the motion and by the increased rotation of the vehicle. The successful duplication of occupant motion in these crashes confirms that a sled test is an effective, cost-efficient means of testing and developing far-side occupant restraints or injury countermeasures.

Most rollover literature is statistical in nature, focuses on reconstructed field data and experiences, or utilizes a very broad pool of dissimilar test data. When test data is presented, nearly all of it involves hard surface rollover tests performed at speeds near 30 mph, with a mix of passenger cars, sport utility vehicles and minivans. Five full-scale dolly rollover tests on dirt of production sport utility vehicles (SUV) and multi-purpose vehicles (MPV) were performed with similar input parameters. The similarities included Federal Motor Vehicle Safety Standard (FMVSS) 208 rollover dolly initiated events, level dirt rollover surfaces, and initiation speeds over 40 mph. All tests were recorded with multiple high-speed and real-time cameras. Additionally, some of the tests included detailed documentation of the rollover surface and the resulting evidence and debris patterns, as well as onboard angular rate sensing instrumentation.

Research focusing on automotive rollovers has garnered a great deal of attention in recent years. Substantial effort has been directed toward the evaluation of rollover resistance. Issues related to crashworthiness, such as roof strength and restraint performance, have also received a great deal of attention. Much less research effort has been directed toward a more detailed study of the rollover dynamics from point-of-trip to point-of-rest. The reconstruction of rollover crashes often requires a thorough examination of the events taking place between point-of-trip and point-of-rest. Increasing demands are placed on reconstructionists to provide greater levels of detail regarding the roll sequence. Examples include, but are not limited to, roll rates at the quarter-roll level, CG trajectory (horizontal and vertical), roll angle at impact, and ground contact velocity. Often the detail that can be provided in a rollover reconstruction is limited by a lack of physical evidence.

Pitch-over events are common in motorcycle accidents, and can be caused by impact to the front wheel and occasionally by hard brake application. In either case, the rider of the motorcycle can be propelled over the handlebars as the motorcycle pitches rear-end up. In accidents caused by pitch-over braking, the accident investigator may be faced with limited evidence and then must rely on analyzing the throw distance of the rider in attempting to reconstruct the pre-accident speed of the motorcycle. This analysis can be complicated by the presence of a second rider (the passenger) on the motorcycle. Pitch over caused by front wheel impact can be similarly complex. Although motorcycle deformation as a result of front wheel impact has been studied [1], circumstances surrounding the nature of the deformation, or the impact itself, may require that the trajectory of the rider be analyzed in order to determine the pre-impact motorcycle speed.

Full-scale vehicle crash testing is often used as an engineering tool to reproduce the dynamic conditions of real-world accidents. The complex and destructive nature of conducting these crash tests makes them very expensive. Often times engineering analysis requires multiple tests wherein occupant motion or vehicle component performance comparisons are made when subject to specific dynamic conditions. For these situations, sled testing becomes the preferred evaluation method. Sled testing allows engineers to reproduce the dynamic conditions of a full-scale crash test in a controlled environment at a fraction of the cost. A particular advantage of sled testing is that only a single vehicle is consumed. Typically the occupant compartment of the vehicle, referred to as a vehicle buck, is mounted to the test sled. The sled and buck can then be subjected to accelerations representative of a particular crash environment.

Testing techniques for creating rollovers have been a subject of much study and discussion, although previous work has concentrated on creating a repeatable laboratory test for evaluating and comparing vehicle designs. The two testing methodologies presented here address creating rollover tests that closely mimic a specific accident scenario, and are useful in accident reconstruction and evaluation of vehicle performance in specific situations. In order to be able to recreate accidents on off-road terrain, a test fixture called the Roller Coaster Dolly (RCD) was developed. With the RCD a vehicle can be released at speed onto flat or sloping terrain with any desired initial roll, pitch and yaw angle. This can be used to create rollover collisions from the trip stage on, including scenarios such as furrow trip on an inclined road edge.