Chapter 4
What You Need to Know about Moves
4-2
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Figure 4-1.
Trapezoidal Move Profile
S-Curve
The acceleration and deceleration portions of an s-curve motion profile are
smooth, resulting in less abrupt transitions, as shown in Figure 4-2. This
limits the jerk in the motion control system, but increases cycle time. The
value by which the profile is smoothed is called the maximum jerk or
s-curve value.
Figure 4-2.
S-Curve Move Profile
Basic Moves
There are four basic move types:
•
Reference Move
—Initializes the axes to a known physical reference
such as a home switch or encoder index
•
Straight-Line Move
—Moves from point A to point B in a straight
line. The move can be based on position or velocity
•
Arc Move
—Moves from point A to point B in an arc or helix
Velocity
Time
Velocity
Time
