Animated Crash Scenes Can Often Give More Complete View, Understanding Of Events Preceding Collision

Patrol officers driving separate cars in Eugene, Oregon one day answer a call about an armed robbery/kidnap suspect, and, after locating him, embark on a wild pursuit through the city’s streets at high speeds. One of the patrol car’s drivers tries to stop the vehicle chase by performing a so-called “Tactical Vehicle Intervention (TVI),” essentially blocking the suspect’s car with his own. The TVI works—temporarily—as the suspect regains control of his vehicle. The suspect then tries to speed away, directly into the path of the primary pursuing patrol car. The two cars collide head-on, and , although no one is injured, the suspect flees on foot. When the suspect pivots toward an approaching officer, the officer shoots him. Amazingly, the suspect continues to flee. By now, a detective unit has arrived on the scene and catches the suspect as he crests a small embankment.

With such a huge and complicated scene to map and diagram, a single scaled diagram, even with the best of details, may not be sufficient to fully show all of the frenzied activity involved between the officers and their suspect. In this instance, therefore, an animated depiction of the scene probably would give a more complete representation of the sequence of events.

Build Animations in PowerPoint

Although not used widely among reconstructionists today, the practice of animating selected collision scenes is gaining momentum. Basically, animation allows for the presentation of a scene or situation in near real-time motion. Traditionally, crash animations, or “movies,” were created by professional firms who specialize in using expensive and difficult animation software. These specialized animations also come with a very high price tag ($30,000 to $60,000 is not uncommon). Obviously, this type of expense is just not in the budget for most investigations. A more economical way to create an animation is to use a software program already available on most computers today, such as Microsoft PowerPoint. With a little experimentation, an investigator can save a series of 2D or 3D slides from his diagram program and combine them in PowerPoint to create an impressive animation.

Example

PowerPoint Slide 1	PowerPoint Slide2	PowerPoint Slide 3	PowerPoint Slide 4
Result of 4 PowerPoint slides converted to an animated GIF in Adobe Image Ready (.5 sec frames)

A PowerPoint animation can show a sequence of screen shots of a vehicle moving to impact, and then to the post-impact moment. It is this sequence of events, including tire mark evidence, that can lead a judge and jury or other parties to understand how the vehicles interacted and moved to their final rest position.

“Many people will do a diagram of a scene as it looked when they got there.” Says Duane Meyers, an accident reconstructionist and trainer with the Wisconsin State Patrol and Great Lakes Crash Analysis, LLC. “That’s what they put into their reports, or print out. That’s fine. It’s forensic evidence to show where the evidence was,” Meyers explains. “But it doesn’t necessarily tell a person how this whole event happened.”

When there is a high uncertainty about the events within an accident, or the scene is so complex that just one reference point—the point where the cars have come to rest after impact—proves too limited for a complete understanding of the scene, Meyers and other reconstructionists like him feel animation can help. To accomplish animation, the reconstructionists first must develop a series of illustrations in his narrative report that outline the sequence of events. The sequence needs to show how the vehicles moved toward impact, where they came from, how they interacted over the crash site, and, eventually, came to final rest. Once this sequence is developed, the reconstructionist can use Microsoft PowerPoint to illustrate, frame by frame, all of the events.

“It’s up to the individual as to how close, in time increments, he wants each frame to be. Obviously, the closer the time element, the smoother the animation will look,” said Meyers, who uses, and teaches, The Crash Zone diagramming program available from The CAD Zone, Inc., Beaverton, Oregon. The Crash Zone, like some other drawing programs, allows users to export images of the collision diagram to a format that can be incorporated into a PowerPoint animation.

To view a streaming video of a PowerPoint presentation, click here

Build Animations in a Video Editor

In addition to Microsoft PowerPoint, illustrators have the option of taking images created in The CAD Zone software and copying them to a video editing program such as Pinnacle Studio, Adobe Premiere, and Avid Xpress DV. They can create the movie in real time or at any speed of their choosing. Standard video in the United States is typically developed at a rate of 30 frames/second. This results in a smooth looking movie without any jerking movements. However, this high frame rate is not absolutely necessary. A video created with 15 frames/second can look quite acceptable.

The key to successful admission of illustrations in trial will oftentimes depend on the accuracy of the illustration relative to time and distance parameters. This applies to whatever form in which the presentation is given.

Animation Gives ‘Sequential’ View

Detective Sergeant Randall Tanghe, of the Hilltown Township P.D. in Pennsylvania, and also a professional reconstructionist, agrees with Meyers that animating vehicle crashes can often clarify scene details. “By bringing an animated crash scene into the courtroom,” contends Tanghe, “the reconstructionist must be able to quantify forensically every still image within the animation. In a courtroom presentation, the recontructionist is demonstrating to the judge and jury a sequential approach of both vehicles based upon what they actually did versus what they could or should have done had both vehicles’ drivers been doing the speed limit,” Tanghe said.
Helpful for Near-Miss Accidents

Why are animated presentations of crash scenes so helpful, even critical, especially in court? As one example, near-miss accidents, which are quite prevalent in cases a reconstructionist encourters, can be best explained through an animated sequence of events from the crash scene. “If the defendant had been doing the speed limit as opposed to, say, a calculated speed of 15 mph over the limit,” Tanghe explains, “we would be able to better show by animation that a driver would have had additional time, and distance, to clear the area of impact. Therefore, no impact would have occurred,” said Tanghe. The animation, he continues, will visually demonstrate the near-miss accident. “It will show the viewing audience the sequence of events as they unfold, and exactly what would have transpired had the speeding vehicle been traveling at the speed limit, as opposed to what actually occurred as a direct result of the excessive speed,” Tanghe said.

In addition to using animation for crash scene diagrams in his professional work, Tanghe also teaches reconstruction courses at the Institute of Police Technology and Management (IPTM) at the University of Florida, Jacksonville, Florida. He uses The Crash Zone, and PowerPoint animations of crash scene diagrams both in his reconstruction work and training classes.

Meyers points out that crash scene animations presented in court can be real-time… to a degree. “I give my presentations in a sequence, whereby the positions are time/distance accurate, but the sequence itself may not be. But you can show the timing of each sequence up to the moment that the crash occurred,” Meyers said. “As the vehicles move in, you can change a displayed time value along with the positions so that the sequence’s frames are time-distance accurate.”

Another benefit of animated sequences of a crash scene is that the animation helps the audience actually see the entire crash event from start to finish versus what normally is just a static diagram often supplemented with too much technical detail from the presenter.

“If all you had was a static drawing created from the results of the crash,” Meyers said, “it would be difficult to describe the entire collision process. But when you can show it through animation, you can show, for instance, how much time was left before drivers could respond. You may be able to show how a collision was unavoidable,” Meyers added. “Or, you can show how each movement of a vehicle is supported by the physical evidence on the ground surface. You can lead the jurors through a logical sequence so they can better understand how you (the reconstructionist) believe this happened.”

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