Use "MOTION" button to access motion
control screens.
Initialization of the motors
After switching on the power for a VME crate, UMAC MACRO chassis and
motor amplifiers all motors are in the passive state: motor amplifiers
are disabled, and servo loops are open. To initialize a motor you will
need a motor control screen
accessible from hierarchical menu "MOTION -> ... -> ... -> ...
-> View Status / Jog / Home motor". This screen is different for
different motor types. Most of them are DC brush servo motors and step
motors. To initialize such motor:
1) Click "Enable" button to enable the servo amplifier. Amplifier
Enable status bit has to alter from "Disabled" to "Enabled".
2) Click "Stop" button to close the servo loop. In Position status bit
has to display a "Positioned" state.
Some motors are DC brushless servo, such as a motor on the goniometer
"omega" rotary stage or motors on the "X" and "Y" stages of the XY
Positioner-9. These motors require to establish rotor position relative
to the motor coils. To initialize such motor:
1) Click "Ini ($)" button. This will use a Hall sensor on the motor to
establish rough phasing with an accuracy of +-15 degrees. Amplifier
Enable status bit should display "Enabled", and In Position status bit
should display "Positioned".
2) Click "Home" button. This will move motor till the encoder index
position.
3) When motor reaches encoder index position "Actual Position(cts)"
field
will be resetted to 0. After that, to perform an exact phasing one
should click the "Sync.Phase Mx71" button. This will copy an exact
phase
value to the phase register.
Four motors are controlled by Geo MACRO drives. These motors are for
the MAR
CCD detector motion. Click "Clear Fault N..." button before
initializing these motors. This
should clear an amplifier fault register on the Geo MACRO drive. Then
proceed
with initialization of the motor as described above.
Homing procedure
Most of the motors at the beamline are used with incremental encoders.
A few step motors have no encoders though. To establish a referenced
position a homing procedure has to be completed, i.e. motion is
performed until the limit switch is engaged, then direction of motion
is reversed and the position of the first index pulse after the limit
switch is disengaged becomes a point of origin for given axis. If
encoder does not have an index pulse, the axis origin is selected at
the limit switch disengaging point. Steps for the homing procedure are:
1) Click a "Home speed Ix23" button to request direction and
value of the motor home speed. This will place a command <Ixx23>
into the "MTR CMD=" field; and PMAC controller response will appear
next to it. If motion controller returned a positive
value, the negative limit switch should be used in the homing
procedure;
otherwise - the positive limit switch.
2) Click "Jog-" or "Jog+" button to run the motor and wait until
motion will be stopped by the limit switch.
The Negative/Positive End Limit status will change its state from "OK"
to "Tripped".
3) Click "Home" button. Motor should move off the limit switch. The
Negative/Positive End Limit status will change its state from "Tripped"
to "OK". The "Actual Position(cts)" field will be resetted to 0.
Exceptions:
1) Goniometer "omega" axis has no limit switches; skip the first and
the second steps, and proceed to the step 3. Rotary stage will be homed
by the encoder index position.
2) Zoom axis on both video cameras have no limit switches nor
encoders; skip the first and the second steps. Click "Jog+" button,
then "Stop" button; this will move motor in the positive direction to
make sure the home switch is not activated; proceed to the step 3. Zoom
will be homed at the lowest magnification.
Homing script
Homing of the motor assemblies automated by Perl scripts can be started
from the hierarchical menu by pressing "TOOLS" -> "Home Beamline
Optics/Endstation motors" -> "Home ...". Script will open an
MEDM screens for affected motors and a terminal window which will show
the progress of homing procedures.
Calibration
Calibration of the motion axes to physical units (millimeters, degrees,
photon energy in keV, etc.) are done with MEDM calibration screens
accessible from the hierarchical menu by pressing "MOTION" ->
... -> ... -> "Calibrate". Slope, offset and possibly other
parameters are used to translate motor counts to physical units.
Troubleshooting
Resetting the Turbo PMAC2 VME
UltraLite motion controller
Soft reset: send a <$$$>
command to the PMAC controller, then reboot the IOC.
Hard reset: cycle the power at
the VME crate, wait for IOC reboot, run homing scripts for affected
motors.
Resetting the UMAC MACRO and
Geo MACRO drives
Soft reset: send a command to
the PMAC controller:
ms$$$0
- resets Geo MACRO #1 (vertical motors for
MAR CCD support)
ms$$$4
- resets UMAC MACRO #1
ms$$$16
- resets Geo MACRO #2
ms$$$32
- resets UMAC MACRO #2
Hard reset: cycle the power at
the UMAC MACRO chassis / Geo MACRO drive.
Run homing scripts for affected motors.
Resetting motor amplifiers
Soft reset (available only for
Geo MACRO drives):
msclrf0
msclrf16
Hard reset: may be required
for high power amplifiers used with brushless DC servo motors.
If "Amplifier enable" LED is off on the AeroTech amplifier while status
at the PMAC controller is "Enabled" - unplug the amplifier power for
5-10-15 seconds and plug it back.
If "Power" LED is flashing on the TA310 amplifier, unplug the amplifier
power for 5-10-15 seconds and plug it back. "Power" LED should be in
the "ON" state.