Mitsubishi Electric MELSEC iQ-F Series FX5 User Manual page 132

The 2-axis circular interpolation control with the center point specified (INC circular
right, INC circular left)
■Operation chart
In the incremental system and 2-axis circular interpolation control with center point specified, positioning is implemented from
the current stop position (start point address) to the position of the movement amount set in [Da.6] Positioning address/
movement amount in an arc path whose center is the center point address (arc address) set in [Da.7] Arc address.
Forward direction
Start address
(Current stop position)
Reverse
direction
Reverse
direction
If 0 is set for the movement amount, the positioning of a true circle whose radius is from the start point address to the center
point address of the arc can be performed.
Forward direction
Reverse
direction
Reverse direction
In the circular interpolation control with the center point specified, an angular velocity is calculated with an assumption that the
positioning target moves at the command speed on the arc using the radius calculated from the start point address and center
point address. The radius is compensated in proportion to the angular velocity moved from the start point.
Thus, if a difference (error) is found between a radius (start point radius) calculated from the start point address and center
point address and a radius (end point radius) calculated from the end point address and center point address, the composite
speed differs from the command speed and as described below.
Error between start point radius
and end point radius
Start point radius > End point radius
Start point radius < End point radius
9 MAJOR POSITIONING CONTROL
130
9.2 Positioning Data Settings
Radius
Arc center point
(Arc address)
Movement amount to end point
Arc center point
(Arc address)
Composite speed
Compared with the speed without an error, the speed becomes slower as the end point address is reached.
Compared with the speed without an error, the speed becomes faster as the end point address is reached.
Movement according to arc interpolation
Movement amount
to end point
Forward direction
Movement amount = 0
Forward direction