
B-63783EN-1/01 7.FEEDRATE CONTROL/ACCELERATION AND DECELERATION CONTROL
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7.1.18.1 Speed control based on changes to acceleration for each axis
Vibration or shocks may occur to the machine in portions where there
is a large change to acceleration, for example, a portion where the
shape specified by the machining program changes from a straight line
to a curved line.
To reduce machining error that may result from vibration or shocks to
the machine when the acceleration changes, speed control based on
changes to acceleration for each axis reduces the tool speed at
acceleration/deceleration before interpolation by obtaining a feed rate
that can keep acceleration changes from exceeding the permissible
acceleration change level set in parameters for each axis.
Example
The following example performs deceleration at a point of tangency
between linear interpolation and circular interpolation because there is
a large changes to acceleration along the Y-axis.
Linear interpolation (N1) → circular interpolation (N2)
Y
X
Vibration due to changes to
acceleration
N1
N2
Tangential
speed
Y-axis
acceleration
Speed
Time
N1
N2
Time
Speed
cceleration
Time
cceleration
Time
Setting a permissible acceleration change level
Parameter No. 1673 is used to set a permissible acceleration change
level for each axis. The permissible acceleration change level is a rate.
If a parameter value is 0, speed control based on changes to
acceleration is not performed for the axis that corresponds to that
parameter value.