Disclaimer: Visualizations presented below used scene and
vehicle surveys, witness statements, vehicle operating characteristics, and
pictures from the scene. The depictions are not intended to represent actual
lighting or weather conditions at the time of the accident
Videos are available in .wmv format
and were presented at the Board meeting on 2/5/02 in Washington, D.C.
Vehicle Dynamics: The truck's approach to the grade crossing was examined. The collision between the truck and the train were simulated. The railroad flashers and gates were simulated to have worked as designed. The speed of the truck on the approach increased from a stop at the truck scales to 15 mph and then the truck slowed to about 7 mph at impact while the train impact speed was 79 mph. Several views of the vehicle dynamics are shown and all are at real-time.
ChaseVew.wmv (2.3 mb)
The second view shows the impact and motion to final rest from a fixed camera position opposite the point of impact so the position of the truck when the signals activate can be easily observed.
FarsideVew.wmv (1.3 mb)
The third view shows the overhead view and the closeness of the truck to the gates. The overhead view also shows that the truck came to rest in the simulation close to the final rest position as surveyed and that the tiremark left on during the simulation overrides the surveyed marks on the timbers.
OverheadVew.wmv (.5 mb)
The fourth view shows the truck from an overhead oblique as it approaches the crossing to show the relative position of the truck in the lanes. This view includes the tiremark as documented by the highway group on the timber crossing. In addition 1-foot square marks are placed on the roadway to highlight the truck's left tires at impact to show how the truck off-tracks with its rear wheels going to the right or inside the front wheels.
ArndGatesMarks.wmv (1.0 mb)
The potential truckdriver's front and side views were investigated and those views are presented.
TrkDrvFrtVew.wmv (1.7 mb)
TrkSdeVew.wmv (.9 mb)
A comparison of an actual test conducted by the Illinois State Police at a calculated speed of 9.0 to 8.2 mph as the truck went around cones that were placed where the gates would be when down and the simulation are presented. This view uses a split-screen format to show the similarities in the actual truck's movements to a simulated truck as viewed from the front. In the simulation the truck is going about 7 mph.
ISPSpltScrn.wmv (.7 mb)
This is a simulation and a movie combined with a sound wave to show the operation of the flashers, gates and bells at the crossing. After the collision a video camera was installed at the crossing to record the activation of the gates. Since the video recorder took a few seconds after activation to start recording, the initial activation of the signals is not captured on film. This unrecorded portion with signal activations is simulated and spliced into an actual nighttime activation at the crossing after the accident. A sound wave was added to represent the bells, which start when the signals begin to flash and ends when the gates are horizontal. A clock was added to countdown the time until the train arrives at the crossing. This video highlights the length of time the signal recorder indicated the system was activated just before the accident.
GatesCountBell.wmv (1.3 mb)
The simulations were produced on an HVETM system using EDSMAC4TM EDVDSTM and EDGENTM programs. All of the programs are trademarks of the Engineering Dynamics Corporation. The software, ReadDataFile, developed by Collision Engineering Associates was also implemented for the simulations.