position to the encoder position within the allowable margin of error, or
“deadband”. Feedback modes are covered more in depth in the full version
of the manual, if you are concerned about irregular sounds or inconsistencies
in the position or trajectory of your stage, it may help to understand the
feedback modes of the MMC-10 controller.
g. Now press the button labeled “Zero” in the position section of the MMCP.
Both the calculated and encoder position should now be set at zero.
Micronix uses relative encoders, so only changes in position are tracked. Our
encoder position is relative to a zero point. A zero point is automatically set
every time the controller is power cycled, and can be manually reset at any
time.
h. In the “Target Pos 1” field in the “Motion” section of the MMCP, enter the
value -1. Click the “Go” button next to this field and the stage will attempt to
move to the absolute position of 1 mm in the negative direction from the zero
point you just set (since we are in open loop, the “Calc” value will read -1 and
the “Enc” value will likely read something less than -1). In this way, you can
set a custom zero point to use as a reference in your motion. Moving to an
absolute position of 0 in closed loop will always return you to this position.
i. It is important to note here that in closed loop, telling a stage to move to a
position it cannot actually reach (i.e. telling a stage with 20mm travel to move
to absolute position 100) will cause the stage to move indefinitely into the
limit. The hard stop detection discussed earlier will only work with the MLN
and MLP commands. If this happens, motion can be terminated by pressing
the “Stop” button in the “Motion” section of the MMCP, or by entering the
text
comma
nd
<axis
number>STP
(stop
c
ommand)
or
<axi
s
number>
EST
(emergency stop command). In general, moving into a hard stop for a short
time (a few seconds) will not cause damage to a piezo motor, but being left
running into a limit for a significant period of time can eventually cause
damage.
j. The values in the “Motion Parameters” section of the MMCP are fairly straight
forward. On a linear stage, acceleration, velocity, and deceleration are
exactly what one would expect. On a rotary stage, the mm/s and mm/s/s
values can be substituted with degrees/s and degrees/s/s. These values do
have maximums depending on the controller settings, which can be queried
in the “Commands” t
ab by entering t
he command <axi
s number>VMX? for maximum
velocit
y
and
<axis
number>
AMX?
for
maximum
accel
eration
and
deceleration.
3. Now you are familiar with the basics of achieving motion with the MMC-10 Piezo
Motor Controller. The full version of the user manual included on the CD that shipped
with your order contains much more detail, including a full command list and pinouts
If you have questions or concerns not covered in these manuals feel free to contact
Micronix support.
Micronix Support:
Phone: (949) 480-0538 x705
