Using Animations to Convey Motion:

  The Hopping Mode


In the 12/3 hopping mode, the twelve cells in the outer ring remain stationary, while the inner three cells hop - appearing to play musical chairs among four slots. The motion seems periodic to the eye, but the cells actually move irregularly in space and time.

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Movie (.43M)

Cells Tracked

The individual cells in the flame front are tracked by segmenting individual frames of videotape and matching corresponding cells in successive frames. We can determine position, size and shape of the individual cells.
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Movie (.03M)

Time-Lapse of Centers

In this view the cell center positions are represented by color-coded dots. The dots are accumulated over each frame of videotape to form a time-lapse representation of the motion. The time-lapse of the cell centers shows the spatial irregularity of the hops. When viewed closely the cell centers appear to move along the sides of a rectangle for short periods of time. The orientation of the rectangle changes as the hopping progresses.
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Movie (.86M)

Animation

This animation of the hopping motion emphasizes the rectangles along which the hopping cells appear to move. The positions during which two cells are stationary are represented by color-coded disks connected by a line. The lines fade gradually as the animation proceeds to improve visual persistence.