Parker Hannifin
Velocity Profile Commands
A basic motion profile for coordinated motion, controlled by an
attached master, consists of acceleration, deceleration, stop ramps
and a velocity. You can further control coordinated motion using
additional velocity profile commands.
Axis motion with gear, cam, or jog offsets are controlled solely by
their associated commands—for example,
CAM OFFSET
,
CAM SCALE
,
GEAR ACC
,
GEAR
RATIO, JOG DEC
, or
JOG JRK
.
NOTE:
To check the setting of a specific motion profile command,
enter the command without any arguments.
NOTE:
To disable a command, set its value to zero.
Use the
ESAVE
command to save coordinated motion and feedback
control values in the controller. Otherwise, the system parameters,
motion profiles, and master and axis attachments are retained by
the controller only until the controller is rebooted or its power
cycled. Then all data reverts to its default values.
Velocity Profile Setup
The following commands further shape and refine the coordinated
motion profile. For more information about each command, see the
ACR Command Language Reference
.
•
F
(Set Velocity in Units per Minute)—sets a move velocity in
units/minute. The
F
command otherwise functions the same as
the
VEL
command.
•
FOV
(Set Feedrate Override)—sets the move velocity manually,
without changing the current
VEL
value. Use
FOV
to
superimpose an additional move onto existing motion.
Typically, the
FOV
provides a manual way to change velocity
from a terminal. You can also assign the
FOV
to an input,
providing users a manual way to initiate the superimposed
move. For more information, see
Immediate Mode
.
•
FVEL
(Set Final Velocity)—sets a final velocity value. When a
STP
value has been set,
FVEL
can be used to set a target final
velocity value. The value is used to slow down between moves,
but not stop. Moreover, a move only ramps down to the
FVEL
value, never up to the value.
•
JRK
(Set Jerk Parameter)—sets the slope of acceleration versus
time profile. An s-curve profile provides a smoother motion
control by reducing the jerk (rate of change) in acceleration
and deceleration portions of the move profile. Because s-curve
profiling reduces jerk, it improves position tracking
performance.
58 Programmer’s Guide
