I'm not sure exactly what happened here but the result was bad - my Paramount became lost.
I was running the Scheduler with a number of long, time-series. The VOEvent receiver was
running. The first time-series was nearly finished when a Catalina event came in. The
default event filter and the observation plan were configured for an immediate interrupt.
The interrupt was acknowledged in the Scheduler but the exposure in progress was not
interrupted (the Scheduler has never interrupted an image set in progress with my system-
this is different issue).
The observation in progress completed normally but then AcquireScheduler crashed. From the
logs, it appears that the Scheduler started the next observation and AcquireScheduler
started the slew but this failed, I suspect because it was already slewing to the event.
This happened shortly after I went to bed. The next morning, I found the telescope
pointing up and stopped. It headed for the floor when I attempted to park it.
The mount problem is reminiscent of an early Paramount issue that came to be known as the
"China Syndrome" where a certain sequence of commands cause the mount to lose home position
and think that home was below the floor to the north. One way I found to trigger this was
to interrupt a slew in progress with the telescope on the east side. I thought this had
been fixed but perhaps not. In any event, it's probably a good idea to wait until a slew
has finished before starting another one.
The Scheduler and AcquireScheduler logs are below:
John

************************************************** ************************************
Log opened at Tue, Aug 18 2009 02:24:13 UTC (actual time)
Scheduler version 3.0.5
Multi-user license: John Farrell
18-Aug-2009 02:24:23.1: Dispatcher started at 18-Aug-2009 02:24:23 UTC
18-Aug-2009 02:24:23.1: Priority: W[0]=1.00
18-Aug-2009 02:24:23.1: Transit Altitude: W[1]=0.70
18-Aug-2009 02:24:23.1: Highest Altitude: W[6]=0.00
18-Aug-2009 02:24:23.1: Lateness: W[5]=0.00
18-Aug-2009 02:24:23.1: Slew Distance: W[2]=0.30
18-Aug-2009 02:24:23.1: Retry Count: W[3]=0.20
18-Aug-2009 02:24:23.1: Meridian Crossing: W[4]=0.30
18-Aug-2009 02:24:23.1: Obs Conditions: W[7]=0.40
18-Aug-2009 02:24:23.1: Rising Plan Delay: in effect
18-Aug-2009 02:24:23.2: ++ Observatory Startup ++
18-Aug-2009 03:09:44.2: Dispatcher cycle time: 10.421875 sec.
18-Aug-2009 03:09:44.2: Acquire data for Observation V0745 Cep...
18-Aug-2009 05:19:11.9: Time-critical VOEvent received for CATOT #908181150924134499 -
Scheduling observations!
18-Aug-2009 05:19:17.2: **DISPATCHER INTERRUPT LEVEL 1 RECEIVED**
18-Aug-2009 05:23:08.6: Acquisition time: 8004.40825 sec.
18-Aug-2009 05:23:08.6: Data for Observation V0745 Cep acquired successfully.
18-Aug-2009 05:23:08.6: Image Efficiency: 89.8%
18-Aug-2009 05:23:08.6: Cycle Efficiency: 99.9%
18-Aug-2009 05:23:11.7: Dispatcher cycle time: 2.984375 sec.
18-Aug-2009 05:23:11.7: Acquire data for Observation OT Cep...
18-Aug-2009 05:23:27.0: SEQUENCER ERROR: Failed to complete acquisition process (see
sequencer log)
18-Aug-2009 05:23:27.0: Data acquisition failed for Observation OT Cep.
18-Aug-2009 05:23:27.0: (ACP reported See sequencer's log file)
18-Aug-2009 05:23:28.0: **EXCEPTION IN SCHEDULER:
18-Aug-2009 05:23:28.0: The telescope is not connected.
18-Aug-2009 05:23:28.0: Traceback:
at ACP.TelescopeClass.get_RightAscension()
at DC3.Scheduler.ACPSequencer.SlewTime(Double RA, Double Dec)
at DC3.Scheduler.Engine.Efficiency(Plan P, DateTime t)
at DC3.Scheduler.Engine.SelectBestPlan(ArrayList PList)
at DC3.Scheduler.Engine.DoSchedulePass()
at DC3.Scheduler.Engine.Run()
18-Aug-2009 05:23:28.4: Run statistics:
18-Aug-2009 05:23:28.4: Observations: 271
18-Aug-2009 05:23:28.4: Considered: 76
18-Aug-2009 05:23:28.4: Completed: 4
18-Aug-2009 05:23:28.4: Skipped: 71
18-Aug-2009 05:23:28.4: Never Eligible: 195
18-Aug-2009 05:23:28.4: Failed: 1
18-Aug-2009 05:23:28.4: Shutter-Open efficiency: 89.30%
18-Aug-2009 05:23:28.4: Overall Efficiency: 99.46%
18-Aug-2009 05:23:59.9: Failed to compact and save database. It may have been locked.
Log closed at Tue, Aug 18 2009 05:23:59 UTC (actual time)
************************************************** ************************************
************************************************** ************************************
ACP console log opened 18-Aug-2009 05:23:13 UTC
This is ACP version 5.1 (build 3, Maintenance release 5.1)
Licensed to John Farrell
05:23:13 This is AcquireScheduler V3.0.6
05:23:13 Custom image file path/names are in use
05:23:13 Custom pre- and post-flip margins are in use
05:23:14 Initializing AcquireSupport V5.1.14
05:23:14 Telescope is ACP->TheSky, driver V1
05:23:14 MaxIm DL/CCD is version 5.07
05:23:14 Imager is BiCCD
05:23:14 Calculated unbinned plate scales (arcsec/pix): H = 1.45 V = 1.45
05:23:14 Calculated field of view (arcmin): H = 27.1 V = 24.7
05:23:17 ACPS Observation #2062 - OT Cep
05:23:17 Pointing updates are enabled
05:23:17 (final image plate solving is disabled)
05:23:17 Starting observation 1 for plan OT Cep
05:23:17 Start slew to OT Cep...
05:23:22 **Script Error**
05:23:22 Source: ACP Observatory Control Software
05:23:22 Message: The script was interrupted before completion. at line 1395 column 9.
ACP console log closed 18-Aug-2009 05:23:24 UTC