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MELSEC-Q
 
9   MAJOR POSITIONING CONTROL 
 
[2]   2-axis circular interpolation control with sub point designation (INC 
circular sub) 
 
 Operation chart 
In the incremental system, 2-axis circular interpolation control with sub point 
designation, positioning is carried out from the current stop position (start point 
address) to a position at the end of the movement amount set in "
Da.6
 
Positioning address/movement amount" in an arc path that passes through the sub 
point address set in "
Da.7
Arc address".  The movement direction depends on 
the sign (+ or -) of the movement amount. 
The resulting control path is an arc having as its center the intersection point of 
perpendicular bisectors of the straight line between the start point address (current 
stop position) and sub point address (arc address) calculated from the movement 
amount to the sub point, and a straight line between the sub point address (arc 
address) and end point address (positioning address) calculated from the 
movement amount to the end point. 
 
Reverse direction
Reverse direction
Forward direction
Movement by circular interpolation
Forward direction
Movement amount to the end point
Movement
amount to the
sub point
Movement amount
to sub point
Movement amount
to the end point
Arc center
Sub point address
(arc address)
Start point
address