Purdue creates animation of 9/11 attack


>>This video illustrates
the efforts of a team of visualization and civil
engineering researchers towards producing a high
fidelity visualization of the September 11, 2001 attack
on the World Trade Center. The visualization has to be
eloquent to the non-expert user. The simulation was placed
into context by modeling and importing the buildings
of the WTC plaza shown here in color into a Google earth
model of Lower Manhattan. A fine element analysis
simulation of the impact between the Boeing 767
and the top 20 floors of the North Tower was
computed using a state of the art simulation code. Then the simulation results
were imported into a state of the art animation system where the visualization
was produced. The simulation tracked the
impact over three-quarters of a second real time. This sequence is 13 times
slower than real time. All the animated geometry seen
here was created automatically from the simulation of the data. [ Pause ]>>This sequence visualizes
the aircraft trajectory between the facade and the
structural core of the building. [ Pause ]>>Notice the oscillation of
the ceiling during the impact. This reverse angle shot
visualizes the important damage sustained by some
of the core columns. Using a camera with a distant
hitter plane [assumed spelling] this sequence simultaneously
visualizes the two floors that sustained most
direct impact damage. [ Pause ]>>Notice the right
engine titanium shaft which traverses the
building virtually intact. [ Pause ]>>Plane debris re-emerges on the opposite face
of the building. The jet fuel in the central and two-wing tanks was simulated
using smoother particle hydrodynamics or SPH. The nearby fuel particles
were lumped together in the animation system
and the fuel was rendered with reflections and refractions
using a retrace material. Notice how the wing tank
fuel disperses first as the wings are considerably
damaged by the facade. The core columns are essential to the structural
integrity of the building. This sequence visualizes the
damage to the core columns and to their connecting
horizontal beams by rendering all other entities
with transparent materials. Here are the core
columns exclusively. These sequences also turn out
to provide a good visualization of the overall deformation
of the aircraft as it enters the building. The simulation did not consider
the effects of the explosion and of the instrument fire. Here, the fuel particles were
used in the animation system to automatically produce a
plausible fire visualization. Apps can be seen in this
side by side visualization, the simulation fuel particles
control the fire computed by the animation system. Elements that out or go
excessive stress are eliminated from the computation by
the FEA simulation code. These eroding elements
correspond to entities that disintegrate such as a slab
of concrete turning into dust. Although they do not
have much relevance from the simulation standpoint,
eroded elements are important for the visualization. Eroded elements are used
in the animation system to automatically create
and control visual effects such as dust and
glass [inaudible]. The visualization produce
leverages of strength of the state of the art
visualization system which models the interactions
in detail based on physics based over principles and of the state
of the art animation system which produces a high
quality visualization of the simulation results. This was made possible by
developing a scalable translator that automatically converts
the simulation [inaudible] data into an animation scene. The translator is
general and reusable in the context of
other simulations.