Parker ACR Series, Руководство программиста

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Parker Hannifin
Cam Profiler
The Cam Profiler controls motion for axes needing precise motion. It
uses an array of target points in relation to an externally sourced
timebase (see SRC command—Set External Timebase—for available
sources). By breaking the motion into discrete target points, the cam
arrives at the exact point needed.
The Cam Profiler provides linear interpolation between points,
regardless of how many points are necessary for the move. All
changes in motion are real time. The Cam Profiler does not compile
motion.
NOTE: The Cam Profiler typically uses a source other than the clock
as its timebase.
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CAM RES (Transfer Cam Offset)—this command either clears or
preloads the cam offset of a given axis and adds the
difference to the current position. It also clears out any cam
shift that may have been built up by an incremental cam.
Homing
The homing operation is a sequence of moves that position an axis
using the Home Limit inputs. The goal of the homing operation is to
return the load to a repeatable starting location.
When the homing operation successfully completes, the controller
sets the absolute position register to zero, establishing a zero
reference position. For servo axes using analog feedback, the
controller sets the voltage register to zero.
The Jog Profiler controls homing operations. If the acceleration,
deceleration, velocity, and jerk values are set for jogging, those
values are also used for homing.
NOTE: It is a good programming practice to declare the motion
profile at the beginning of every jog subroutine. Doing so
ensures the correct motion values are used for a jogging or
homing routine, regardless how the program branches to a
subroutine.
NOTE: A homing routine cannot be started for an axis that is
already in motion.
Making Motion 77