Delta Tau GEO BRICK LV User Manual
Turbo PMAC User Manual
282
Writing and Executing Motion Programs
Circular Blended Moves
Note:
In order for Turbo PMAC to do circular moves, coordinate-system parameter Isx13
must be greater than zero. See below for details.
must be greater than zero. See below for details.
Turbo PMAC allows circular interpolation on the X, Y, and Z-axes in a coordinate system. As with linear
blended moves, TA and TS control the acceleration to and from a stop, and between moves. Circular
blended moves can be either feedrate-specified (F) or time-specified (TM), just as with linear moves. It is
possible to change back and forth between linear and circular moves without stopping.
blended moves, TA and TS control the acceleration to and from a stop, and between moves. Circular
blended moves can be either feedrate-specified (F) or time-specified (TM), just as with linear moves. It is
possible to change back and forth between linear and circular moves without stopping.
Specifying the Interpolation Plane
The first thing that should be done in preparing for a circular move is to specify the orientation of the
plane that will contain the circle. This is done by specifying the normal vector to that plane with the
NORMAL command. The arguments of this command are the component magnitudes of the vector: I (X-
axis direction), J (Y-axis direction), and K (Z-axis direction). A typical command might be NORMAL
I0.866 J0.5 K0.0. The length of the normal vector specified here is not important; only the ratio
between the component magnitudes (which determines the direction) is.
plane that will contain the circle. This is done by specifying the normal vector to that plane with the
NORMAL command. The arguments of this command are the component magnitudes of the vector: I (X-
axis direction), J (Y-axis direction), and K (Z-axis direction). A typical command might be NORMAL
I0.866 J0.5 K0.0. The length of the normal vector specified here is not important; only the ratio
between the component magnitudes (which determines the direction) is.
Standard Planes
To specify the circles in the XY plane, command NORMAL K-1 (equivalent to G17 in machine-tool
code). Similarly, for circles in the ZX plane, command NORMAL J-1 (G18 equivalent); for circles in the
YZ plane, command NORMAL I-1 (G19 equivalent).
code). Similarly, for circles in the ZX plane, command NORMAL J-1 (G18 equivalent); for circles in the
YZ plane, command NORMAL I-1 (G19 equivalent).
Clockwise Direction Sense
The directional sense of the normal vector is right handed. The standard clockwise sense is obtained by
using normal vectors that point in the negative direction along their axes.
using normal vectors that point in the negative direction along their axes.
Circle Modes
To put the program in circular mode, use the program command CIRCLE1 for clockwise arcs (G02
equivalent) or CIRCLE2 for counterclockwise arcs (G03 equivalent). Any other move mode command –
LINEAR, RAPID, PVT, or SPLINEn – will take the program out of circular move mode. LINEAR will
restore you to linear blended moves. Once in circular mode, a circular move is specified with a move
command specifying the move endpoint and either the vector to the arc center or the distance (radius) to
the center. The endpoint may be specified either as a position or as a distance from the starting point,
depending on whether the axes are in absolute (ABS) or incremental (INC) mode (individually
specifiable).
equivalent) or CIRCLE2 for counterclockwise arcs (G03 equivalent). Any other move mode command –
LINEAR, RAPID, PVT, or SPLINEn – will take the program out of circular move mode. LINEAR will
restore you to linear blended moves. Once in circular mode, a circular move is specified with a move
command specifying the move endpoint and either the vector to the arc center or the distance (radius) to
the center. The endpoint may be specified either as a position or as a distance from the starting point,
depending on whether the axes are in absolute (ABS) or incremental (INC) mode (individually
specifiable).