Mitsubishi Electric MELSEC iQ-R RD75P4, User Manual

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3 MAJOR POSITIONING CONTROL
3.2 Positioning Data Setting
107
3
INC circular right, INC circular left
■
Operation chart
In the incremental system and 2-axis circular interpolation control with center point specified, the positioning is performed
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.
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.
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 follows.
Error between start point radius
and end point radius Composite speed
Start point radius > End point radius Compared with the speed without an error, the speed becomes slower as the end point address is reached.
Start point radius < End point radius Compared with the speed without an error, the speed becomes faster as the end point address is reached.
Radius
Movement by circular interpolation
Forward direction
Forward
direction
Start point address
(current stop position)
Arc center point
(arc address)
Movement amount to the end point
Reverse direction
Reverse
direction
Movement amount
to the end point
Arc center point
Reverse direction
Forward direction
(arc address)
Reverse direction Forward direction
Movement amount = 0