On Dec 6, Dario, Frederic and Yuji showed to Koji Noda and Daniel Mazin how to operate the new ALS. The idea was to do an unlock and lock again, as the weather was still bad. The automatic part went more or less OK ending in error state (excpected). We then went to EAST ALS to open the main actuator manually. After moving the actuator manually, the status of the ALS was either locked not unlocked. We realized that secondary sensor for South part was reacting incorrectly (close to metal OFF, far from metal ON), and we thought it is the reason. We removed the endswictch screw but the status did not change. After pressing again Unlock we realized that the secondary South plier squeezed the sensor cable and destroyed it (see Attachment 1). We consulted Ino and closed the ALS EAST manually (all three actuators) because the eather was getting worse.

Next day, Dec 7, we (Daniel and Koji) examined the sensor cable and confirmed it is completely distroyed. We introduced a patch cable and few adapters as a temporary repair (See attachements 2,3,4 and 5). We confirmed the reading of the pressure of the South and North sensors of teh secondary pliers are good again (attachment 6). See pictures.

Last week we put in sevice the new ALS completly modified:

_ Main System with new reducer.

_ New Speed parameters for Main System (motor is at full speed but due to reducer the spped is slow). Decceleration sensors not installed since the speed is very slow.

_ All the sensors were replaced by new ones (2 logic embedded in each sensor (NC + NO) ) = only one type of sensor in the ALS. Sensor with connector to ease maintenance.

_ All sensor cabling were changed and new ducts were installed to ease maintenance.

_ The damaged cable of the loadcell was welded again and protected (Heat shrink tube + tape).

_ Add mechanical part to protect loadcell cable when opening over the opening position. It's now impossible to damage Loadcell cable.

_ Increase speed of plier. We add a deceleration sensor in each plier.

_ All the sensors support are new to avoid dammage if there is over position due to manual operation.

The ALS is now functionnal with human interface. The system are so slow 180s !!!, They were not integrated into automatic cycles.

Shifters must manage the Opening/Closing of the ALS at the Start/End od telescope operations.

A new error code is ride up if a door is opened during motion (3002).

Here is the first entry in the DRIVE ELOG logbook

• To define precisely the correction to apply to Azimuth positionning, a set of movements have been done to calculte the correction coefficient.
• A scan from 0 deg. to 270 deg. with a step of 10 deg. and a reverse scan from 270 deg. to 0 deg. with a step of 50.deg realized to have a better approximation

Many parkin operations done. To confirm the different movements , a Parkin test with a azimuth position 20 and Elevation 70.

This is to validate the complete "Parkin" scenario with "random" az and el positions

Many differents succesfull  "goto position" operations ... MOS configuration file (XML) modified to aplly to correct Azimth and Elevation ranges for secure movement 

• GotoPosition azimuth range : [-126..354]
• GotoPosition elevation range : [0..75]
• FastGotoPosition azimuth range : [-96..324]
• FastGotoPosition elevation range : [0..50]

Start of the tracking debug ==> PLC and MOS 

Pointing to polaris ==>

Azimuth = 0.808

Elevation = 59.941 + 1 degree (correction)

Same operations as yesterday ==> pointing to Polaris with the same coordinates

Same operations as yesterday ==> Polaris position

. Fisrt day of the high speed drive tests with IFAE team.

• Tests for tuning and generating motor plots at 10% (0.0234 Rad/s) of the maximal speed (GRB alert speed)
• Tuning of the emergency stop from 0.05 Rad/s2 up to 0.2 Rad/s2
• 6 movements at 25% speed. (from -90 to 270)
• repositionnning to -90 at 40% 
• movements from -90 to 270 and reverse at 40%
• 3 movements from -90 to 270 and reverse at 60%  : the FW generates an alarm and the drive stops the movement.
  • The FW level was ok but the the status (GRB Fast Rotation and UPS system) got red.
  • Koji has been contacted to look at this issue.

• The FW issue is not solved . No movement can be done
• The FW is going to be restarted ==> It takes several hours to put it down and up again
• Drive movement are stucked 

During a park-in action , the acces tower did not close correctly.

• Test at 60% maximal speed from -90 to 0
  •  Check of the FW discharge : No error (FW 2 : 95% FW1 : 100%)
• Test at 60% maximal speed from -90 to 270
  • Check of the FW discharge ==> Error (FW 2 : 90 % FW1 : 100%)
  • Drive stops at 250 degree.
  • Power consumption = 60kw
•  

• On Thrusday :
  • new movements at 45% from -90 to 270 have been done.
  • No possible movement at 60% because the FW and UPS issues are not solved yet
    • Ino will back on site when HITACHI team will be on site for FW maintenance
      • Tests at 60% will be done to validate (or not) the correction applied by Hitachi team.

• Regulation of the motors (PID) for slow and fast tracking and motor oscillations.
• Implementation and Debugging of the Semi-Expert control software for the drive.
  • GUIs + MOS plugin (OPCUA Server)
•  Results are quite encouraging in good wheather condiftions.
  • additionnal tests in different (wind) conditions are envisaged to validate completly the process

• Tracking at position :
  • RA = 101.288541 RA Offset = -0.6
  • DEC = -16.71343 DEC Offset = 0.7

During this 2 weeks we solve this problems:

_ Park In: Sometimes the final locking position was too limit and the "In Position" sensor was lost

During this weeks we solve this problems:

_ Park In: Sometimes the final locking position was too limit and the "In Position" sensor was lost during the locking witch put the sytems in bad state vs safety constaint (we can't unlock if the sensor In Position is not active). So now the final poition is now adjusted dynamically with the difference betwwen motors and encoders to be sure to stop on torque limit. No more problems since this modification.

_ Problem of communication between the 2 main PLC of the Drive. Due to this error randomly the PLC receive a 2ndTracking command after a Cancel Command. An other random error is to receive the Start Tracking before the Goto Position witch gives errors in the PLC sequence. Communication was rewritten between the 2 PLC. No more problems since this modification.

_ Some change were done in Cancel and Emergency Stop sequence.

_ Now the Power and the Intensity of Main Electrical Cabinet can be available in the OPCUA of the Drive.

_ The High speed of west ALS was decreased since sometimes the variator gives overspeed error. The speed are now identical between the two ALS

+ other minors improvement.

After tracking Mk421, we abort current action (acknowledged) and try to go to a new source: RA=308.1, Dec=40.96. Drive Control refuses these parameters ("check your parameters").

General Abort without effect for 2 minutes. Called expert (Ino). He will look into it.