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This paper presents a unique derivation of airborne trajectory analysis equations from the classical physics equations of uniformly accelerated motion. These trajectory analysis equations are applied to an example problem with realistic real world values. A current widely utilized equation of human trajectory analysis ignores an important cosine function in the calculation of horizontal launch velocity. It is shown that ignoring this cosine function can yield significant error in calculations. A graph is derived from published data on freefall sky diving. This graph can be referenced to adjust calculated velocities for the effects of air drag. It is shown that prior published data which has been widely utilized within the accident reconstruction profession, is inaccurate. A simple method for the application of the derived equation and data to real world problems is outlined.

For sometime, accident reconstruction animation has been limited to graphic workstations running expensive animation software. Only large companies could afford the ability to generate these animations. With the advent of 486 based personal computers and a few specialized, but relatively inexpensive programs, financial considerations are no longer a constraint. Accident reconstructionists can now create their own animations for courtroom presentations. This paper discusses how accident reconstruction animation is produced using a personal computer and Autodesk's 3D Studio. An overview of the 3D Studio software package is given, and the application of 3D Studio for accident reconstruction animation is described. Examples are given of the generation of three dimensional geometries, including accident sites and the vehicles involved. The process of animating the reconstruction and the assurance of time accuracy is described.

The Combined Airborne Tumbling Analysis Procedure Using Laws of motion to determine Throw speed (CATAPULT) for a pedestrian is compared to the published results of vehicle/pedestrian impact testing. Testing by the authors demonstrating the mechanics and dynamics of an object tumbling to rest following a known trajectory is presented. It is shown, that although during ground tumbling individual impulses of a pedestrian with the ground are what slow the pedestrian, with restitution occurring between these impulses, the use of an average drag factor of 0.5 over the total distance tumbled produces accurate results for initial speed.

Staged motorcycle-to-car and motorcycle-to-barrier collisions were conducted with seventeen early 1990's models Kawasaki 1000 motorcycles. The impact speeds into the barrier and cars were varied between 10 and 49 MPH. The purpose was to observe the change in motorcycle wheelbase, and characterize motorcycle-to-car and motorcycle-to-barrier crush profiles. These crash tests will expand the existing motorcycle crash test database. The vehicles were instrumented with tri-axial accelerometers to facilitate the analysis of forces, speed change, and stiffness. Some of the crash tests were recorded by high-speed video cameras. This paper characterizes the data collection system, summarizes the data collected, and lists the parameters that characterize the collision. Crush data and vehicle rest positions were recorded by typical reconstruction methods.