Understand the Graphs

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Understand the Graphs

Motion

Motion is an abstract concept. You cannot buy a motion off eBay, for example.

Motion design software is only useful if the motion is visible. The easiest method is to plot a motion as a graph - that is, MotionDesigner.

A different method is to move machine-elements in a model with the same motions as the motion graphs - that is, MechDesigner.

Motion Graphs in MotionDesigner

You can see up to four graphs in MotionDesigner: Position, Velocity, Acceleration, and Jerk -  the four important motion-derivatives.

Use the View toolbar > P, V, A, & J icons to show or hide a graph of each motion-derivative.

You must show a minimum of one graph.

GST-MotionDesigner-MotionOnlyExample-Understanding

You should understand:

1r X–axis

The X-axis units and Motion-Width of each Motion can be different.

Typically, the X-axis units are degrees and the Motion-Width is 360 degrees - equal to the Master Machine Angle in MechDesigner.

Other units for the X-axis are: radians, cycles*, seconds, milliseconds - see Edit toolbar > Active Motion Settings / Configure Motion

* We use Machine Settings > Cycles/Minute to control the time period of one cycle.


2r Each motion-derivative is the same motion.

We show for you the motion-derivative of the same motion above each other.

If you edit a motion-value in one of the motion-derivatives, you automatically change the shape of the other motion-derivatives.


3r Split the motion into Segments

It is easier to design a motion when you split it into segments. However, too many segments are difficult to manage.

Each segment has a Motion-Law, which is defined by a mathematical function.

You can change the Motion-Law of each segment with the Motion-Law Selector  - a drop-down box below the graph-area..


4r Blend-Points join the segments

Blend-Points join the segments end-to-end.

Blend-Points are also called Nodes.


Names we use in this help for Segments:

Selected-Segment - the segment that you click, it has a different color

Previous-Segment - one segment before (to the left) the Selected-Segment

Next-Segment - one segment after (to the right) of the Selected-Segment

First-segment - the segment at the start of the motion - see also Blend-Point Editor > X-axis value > Motion-Start

Last-Segment - the segment at the end of the motion

Notes:

The end of the Last-Segment is at the start of the First-Segment.

When you click a segment, it becomes the Selected-Segment.