Danaher Motion
06/2005
Groups
M-SS-005-03 Rev
E
123
6. 5
V
ELOCITY
A group’s scalar velocity properties are always the orthogonal combination of
the respective axes' velocity properties. Group velocity properties include:
VELOCITYCOMMAND
vector property
VELOCITYFEEDBACK
vector property
VELOCITYCRUISE
scalar property
VELOCITYFINAL
scalar property
VELOCITYMAX
scalar property
VELOCITYOVERRIDE
scalar property
Each of these properties operates as its axis equivalent and are clearly
defined in the
SERVOSTAR
®
MC Reference Manual
.
6. 6
L
IMITS
Group limits are similar to limits placed on axes. Limits can be imposed in
two ways: they can be checked realtime, or they can be checked only for
subsequent actions.
6.6.1. Generator
Generator limits affect subsequent commands to the motion generator. For
example, if you change an acceleration limit, this affects subsequent motion
commands but has no effect on the current motion.
6.6.2. Realtime
The MC checks realtime limits each SERCOS update cycle. For example,
exiting position error of every axis is monitored each SERCOS cycle.
6.6.3. Position
Position limits are imposed solely by the axes and are checked at the
beginning of every movement. If one of the target’s points exceeds its limit,
the whole movement is rejected. There are no group position limits. There
are also several limits in the MC related to position:
Set
POSITIONERRORMAX
(
PEMAX
) to the total position error the system
can tolerate during operation (maximum square root of the sum of squares):
MyGroup.PEMax = 1.0
Set
POSITIONERRORSETTLE
to the total position error the system can
tolerate to be considered in position.
MyGroup.PositionErrorSettle = 1.0
TIMESETTLE
(
TSETTLE
) is the amount of time required before an axis is
considered settled (
POSITIONERROR<POSITIONERRORSETTLE
). After a
MOVE
/
CIRCLE
profile is complete, the MC waits for
POSITIONERROR <
POSITIONERRORSETTLE
for
TIMESETTLE
milliseconds before setting
ISSETTLED
.
TIMESETTLEMAX
(
TSETTLEMAX
) defines the amount of time allowed for
settling after a move has been commanded. After the
MOVE
/
CIRCLE
profile
is complete, the MC waits
TIMESETTLEMAX
milliseconds for settling. If the
position error remains above
PESETTLE
, an error is generated.
