Associating 2D Image Planes with the Model

The Model sub-tab allows you to position the image plane in a model space based on some reference motion.
  1. From the 2D Image Plane tab, click the Model sub-tab.
  2. Select one of the available options from the Associate image with model drop-down menu.
    OptionDescription
    None The image plane will not be associated with anything and will remain in the current space in which it is aligned.
    Model Label Associates the image plane to the model tracking system. Select the model file from the drop-down menu to apply the tracking from the model to the image plane also. The tracking behavior of any associated model based tracking systems will be applied to the image plane.

    This is useful for studying the deformation motion with the tracking system applied (provided that there is no out of plane rotation in the video).

    Important: This option is only applicable if a tracking system has been applied to a model.
    Video tracking Allows you to select a point on a video image plane and fix it in space (with regard to the model). The image plane will move to keep the same position of the point in global space.

    Video tracking is useful in situations when the physical test set up differs from the simulation set up. For example, a sled mounting the structure and occupant may be moving in one direction in a physical test, however the simulation is set up to have the structure moving in the opposite direction. In these scenarios, a reference point on the video is maintained in position with respect to the model by applying Video tracking.

    If the Video tracking option is selected, the following options also become available:
    Track Point Enables the input collector and allows you to pick a point in the image plane viewing area.
    Calculate

    Calculates the position of the selected point for each frame of the video/animation. The image plane will translate with each frame of animation to maintain the model space location of the point. If the calculation is unsuccessful, a dialog will appear stating that either the calculation for that point was not accurate, or that it failed after a certain frame.

    In order to successfully track a point, it must be visible in the graphics area. If the point disappears from the video, the calculation will either return no data after that frame (causing the tracking to stop), or false data (causing the image plane to translate incorrectly).

    The current frame when a track point is selected becomes the starting frame for tracking. No tracking will occur prior to that frame, nor will the tracking circle be drawn before that frame.

    After calculating, you may choose to work with the tracking point as selected or you may pick another point. The time to track a marker and calculate the position across many frames can be significant in high quality videos. A fast tracking mode is enabled by default (Preferences > Options > Performance > Image Planes) to speed up the computation. You can however disable this option for more accurate tracking, at the expense of time, if the fast tracking mode is not producing desirable results.

    Show tracking circle Draws a circle on the image plane which is centered on the calculated position of the selected point.
    Color Allows you to choose the color of the tracking circle.
    Window track size Window track size denotes a bounding region to search for the marker that is tracked.