Yaskawa LEGEND-MC - Manual (Page 271)

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LEGEND-MC User’s Manual
Independent Axis Positioning
In this mode, motion between the specified axes is independent, and each axis follows its own profile.
The user specifies the desired absolute position (PA) or relative position (PR), slew speed (SP),
acceleration ramp (AC), and deceleration ramp (DC), for each axis. On begin (BG), the LEGEND-MC
profiler generates the corresponding trapezoidal or triangular velocity profile and position trajectory. The
controller determines a new command position along the trajectory every sample period until the
specified profile is complete. Motion is complete when the last position command is sent by the
LEGEND-MC profiler.
NOTE: The actual motor motion may not be complete when the profile has been completed, however, the
next motion command may be specified.
The Begin (BG) command can be issued for all axes either simultaneously or independently. X or Y axis
specifiers are required to select the axes for motion. When no axes are specified, this causes motion to
begin on all axes.
The speed (SP) and the acceleration (AC) can be changed at any time during motion, however, the
deceleration (DC) and position (PR or PA) cannot be changed until motion is complete. Remember,
motion is complete (AM) when the profiler is finished, not when the actual motor is in position. The Stop
command (ST) can be issued at any time to decelerate the motor to a stop before it reaches its final
position.
An incremental position movement (IP) may be specified during motion as long as the additional move is
in the same direction. Here, the user specifies the desired position increment, n. The new target is equal to
the old target plus the increment, n. Upon receiving the IP command, a revised profile will be generated
for motion towards the new end position. The IP command does not require a begin. NOTE: If the motor
is not moving, the IP command is equivalent to the PR and BG command combination.
Command Summary - Independent Axis
The lower case specifiers (x,y) represent position values for each axis. The Legend-MC also allows use
of single axis specifiers such as PRY=2000.
Command Description
PR x,y Specifies relative distance
PA x,y Specifies absolute position
SP x,y Specifies slew speed
AC x,y Specifies acceleration rate
DC x,y Specifies deceleration rate
BG XY Starts motion
ST XY Stops motion before end of move
IP x,y Changes position target
IT x,y Time constant for independent motion smoothing
AM XY Trippoint for profiler complete
MC XY Trippoint for "in position"