Mitsubishi Electric MELSEC iQ-R RD75P4, User Manual

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3 MAJOR POSITIONING CONTROL
3.2 Positioning Data Setting
105
3
ABS circular right, ABS circular left
■
Operation chart
In the absolute 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 address (end point address) 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 the end point address (positioning address) is set to be the same as the start point address, the positioning of a true circle
whose radius is from the start point address to the center point 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
Reverse direction
End point address
Start point address
(current stop position)
Arc address
Forward direction Reverse direction
(positioning address)
=
Arc center point
Reverse direction
Forward direction
(arc address)
(current stop position)
Start point address
Reverse direction Forward direction
End point address
(positioning address)