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How to Understand the Graphs
see also: Motion Design: Example 1: Indexing Motion

Motion is an abstract concept, rather than something concrete.  It is difficult to order a motion off eBay for example. 
Motion is the sometimes defined as the rate of change of position with respect to time. (see FAQ: What is a Motion?)
Once position is defined, the other graphs can be automatically generated by calculus.

For a motion design software package to be useful, the motion must be made visible by representing it somehow. The easiest and most natural way is to plot a motion in a graph, and that is what MotionDesigner does, too.

There are four graphs available in MotionDesigner :  
  • Position, 
  • Velocity, 
  • Acceleration and 
  • Jerk. 
    You can use the , , , and icons in the View Toolbar, respectively, to toggle the graphs on and off.  
    When showing, the position graph is always drawn at the top, then velocity, then acceleration, then jerk in order.  Toggling a graph off and on will not change this precedence.

    FIRST IMPORTANT POINT
    You will notice that only the bottom graph displays the X-Units.
    This is because all the graphs (Position, Velocity, Acceleration, and Jerk) are always drawn exactly above each other and so an X-Value is common to all the graphs.  
    At any single point along the X-Axis the motion has a single value (except at a motion discontinuities) of Position, Velocity, Acceleration and Jerk). 
    If you use the Sweep Display you can display and read these values precisely for any X-Axis value.

    SECOND IMPORTANT POINT
    It is important to realise that, for a particular motion design, the SAME MOTION IS BEING DISPLAYED ON ALL THE GRAPHS.  THE DIFFERENCE IS ONLY THE MOTION DERIVATIVE being drawn.
    Therefore, any one graph "contains" all the motion data necessary to fully define the motion.  However, humans find it difficult to integrate and differentiate accurately, and so, all the useful motion derivatives are provided for you.


    Of course, the main purpose of MotionDesigner is to design a motion rather than plot a recorded motion, although you can upload a list of data to plot if you wish.(see Position List or Acceleration List Segment Types).

    THIRD IMPORTANT POINT
    Following on from the "Second Point", a blend-point at a certain X-axis value on the position graph is the same blend-point at the same X-Axis value on the other graphs. 


    Graph Units
    The Y Units for each graph are displayed vertically to the left of each graph.  
    The common X unit  for all the graphs is displayed at the bottom of the graph.
    The Y Values of the horizontal graph grid lines are shown to the left of the graphs.
    The common X Values of all the vertical graph grid-lines are shown at the bottom of the bottom graph.

    Blend-Points - The small circles along the graphs!
    You can see small round circles on the plotted motion graphs.  These are the Blend-Points. They connect the Segments together 
    You will notice that the blend-points are at the same X-Axis value in all the graphs.

    The Red line of the Graph
    The Red line of the graph is the Selected Segment