Point Trajectories
Use a Point Trajectories plot to visualize trajectories of geometric points in 2D () and 3D (). For example, you can use it in a time-dependent multibody dynamics model to plot the trajectory of a geometric point, cut point, or a user-defined trajectory along with the actual moving bodies. Add a Color Expression, Deformation, or Filter (see Filter for Point Trajectories) subnode as needed. Right-click a 2D Plot Group or 3D Plot Group to add this plot from the More Plots submenu.
Go to Common Results Node Settings for links to information about these sections: Data, Title, Coloring and Style, and Inherit Style. See below for the sections specific to this plot: Trajectory Data and Selection.
The Point Trajectories plot creates trajectories not for the actually selected time, parameter, or frequency value but for all values lower or equal to the selected value.
There is an additional setting under Coloring and Style for this plot. The Type of Point Style available includes Comet tail. Comet tail plots provide a convenient way to indicate the direction of travel of points at a given point in time. The tail of the comet typically points in the opposite direction to the point’s velocity — so visually, it is the same as the tail of a comet approaching the sun. See Defining the Coloring and Style for the Comet tail settings.
Trajectory Data
Select a source for the Plot data: Global or Points (the default).
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If Global is selected, enter the coordinates, as global expressions or numbers, for a point in the x-expression, y-expression, and z-expression fields.
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If Points is selected, enter expressions that are valid at the location of the points in the x-expression, y-expression, and z-expression fields. The expressions can include the time and the space coordinates, for example. You select the points that you want to plot trajectories for in the Selection section below and by clicking directly in the Graphics window.
To assist in picking an expression, click the Replace Expression button () above the text fields to choose from a number of available scalar variables.
Selection
This section is only available when you select Points from the Plot data list. It contains tools for selecting points in the model geometry by clicking directly in the Graphics window, for example (see About Selecting Geometric Entities for details).