Aerotech UNIDEX 600 Series, Руководство пользователя

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Parameters U600 User’s Guide
C-66
Aerotech, Inc.
Version 1.4
The lower feedrate value enforced by this task parameter will be such that the largest axis
acceleration/deceleration that will occur during the arc/circle, will be equal to the limit
provided by this parameter plus the value of the AccelRateIPS2 task parameter
(maximum acceleration during a 360 degree circle is F * F / R, where; F is the feedrate,
and R is the circle radius). The units of the parameter value are inches / (second squared).
The controller computes the arc acceleration for an axis, as the maximum
acceleration that the axis would be subjected to during an entire circle at the given
arc radius, at the given feedrate. For arcs traveling through short angles, the actual
acceleration an axis is subjected to may be smaller than that the controller calculates,
causing the controller to slow down more than necessary. Note, that the maximum
acceleration of an axis during an arc occurs when the arc is tangent to that axis. For
example, the maximum acceleration of the X axis (F*F/R) during an arc occurs when
the tangent to the arc is parallel to the X axis.
If G301 mode is active, the controller will look-ahead multiple moves, and slowdown
many moves before the change in velocity. However, the maximum number of moves
ahead of the CNC block, the controller is able to slow down as determined by the
MaxLookAheadMoves task parameter. Also, there are also some other instances where
this parameter will do nothing, due to limitations in the look-ahead process.
C.4.10.1. Calculating the value of the BlendMaxAccelCircleIPS2
Task Parameter
This parameter should be set to the maximum value that does not cause excessive
excitation to the mechanics, adversely affecting part quality. The exact value required for
your system must ultimately be determined by trial and error; dependant upon your
mechanics, support structure, part geometry, required accuracy, etc. The
BlendMaxAccelCircleIPS2 task parameter may be set to the lesser value of the two axes
ACCELRATE axis parameters, as a very rough starting point.
The ACCELRATE must be converted from machine counts / second / second to inches /
second / second, as follows:
BlendMaxAccelCircleIPS2 <= ACCELRATE / CntsPerInch
C.4.11. CannedFunctionID
This task parameter causes the specified Canned Function to execute on the implied
(current) or specified task. The Canned Function must first be defined via the
SETCANNEDFUNCTION CNC command. It may also be executed via the
EXECANNEDFUNCTION CNC command.
C.4.12. ChordicalSlowdownMsec
This task parameter affects the speed and accuracy of contoured CNC program blocks.
This is accomplished by varying the Update Time of the CNC Profiler or the velocity of a
CNC Program block. A CNC program block will always move at the lesser of the two
velocities defined below.