Delta Electronics DVP15MC11T, Operation Manual

Page: 481 / 601

DVP15MC11T Operation Manual
11
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The slave axis follows the master axis to make the synchronous cam motion by using the
MC
_CamIn instruction. In the synchronous cam motion, the corresponding relationship between the
master axis position and slave axis position is based on the pre-planned cam relationship (the cam
curve or cam table). The process in which the slave axis position is calculated through the master
axis position is illustrated as follows.
Ma ste r axis
p osition
%
Mast er
Abs olute
Mas ter a xis
ca m phas e
CA M
Slave axis
c am pha se
S la ve
A bs olu te
Original v alue of
Slav e pos it ion increme nt
F in al value o f
s la ve po sition inc rement
Ca lc ulate slav e
ta rg et pos ition
Slave ax is
posit io n
Mas te r Of fse t
Mas ter S caling
Slav e Off set
S la ve Sc alin g

MasterAbsolute and SlaveAbsolute
The MasterAbsolute parameter is used for specifying the corresponding relationship between the
master axis position and the cam phase. As MasterAbsolute is TRUE, the master axis position and the
cam phase are in an absolute relationship. As MasterAbsolute is FALSE, the master axis position and
the cam phase are in a relative relationship. For SlaveAbsolute, the explanation is similar to that of
MasterAbsolute .
MasterAbsolute and SlaveAbsolute work at the moment when the engagement starts. That is to say that
the corresponding relationship between the axis position and cam phase is built at the beginning of the
engagement. (
NOTE: The corresponding relationship is not built at the time when the MC_CamIn
instruction execution begins but when the engagement begins.) After that, the cam phase is calculated
according to the corresponding relationship.

Relative mode
The master axis position and its cam phase are in the relative relationship as the MasterAbsolute
parameter is FALSE. That is to say, the master axis position corresponds to its cam phase 0 at the
time when the engagement starts. After that, the master cam phase will be calculated according to
the corresponding relationship. For example, the master axis is in relative mode, the maximum
value of the master axis cam phase in the cam relationship is 360 and the master axis position is
180 at the time when the engagement starts. So the master axis position 180 corresponds its cam
phase 0; the master axis position 200 corresponds to its cam phase 20 (20= (200-180) %360) and
so on.
In this circumstance, the master axis position corresponds to its cam phase as shown in the
following figure.
As the SlaveAbsolute parameter is FALSE, the slave axis position and its cam phase are in the
relative relationship. That is to say, the slave axis cam phase and the master axis cam phase meet
the planned cam relationship at the time when the engagement starts. If the slave axis is in relative
mode, the method of being sure of the slave axis cam phase is different from the master axis.
When the slave axis cam phase is sure, it should meet the condition that the slave axis cam phase
and the master axis cam phase meet the planned cam relationship at the time when the
engagement starts.
For example, the slave axis is in relative mode, the maximum value of the slave axis cam phase in
the cam relationship is 360 and the slave axis position is 100 at the time when the engagement
starts. If the master axis cam phase is 0 at the moment (and the slave axis cam phase is 0 as
required in the cam relationship), the slave axis position 100 will correspond to its cam phase 0 as
shown in the following circumstance 1. If the slave axis cam phase is 200 as required in the cam
M ast er ax is c am phas e
Mas t er ax is po sit i on
0
18 0 -1 80 -540 540
360
900
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