Recent notes and issues:

About June 2, 2015: Nav upgrade for Ventana is causing a ~150 m error.

August 30, 2013 Ventana (From Dawe); CASIUS offsets seem more reasonable than last calibration however Sonardyne is still concerned about the 'movement' of
the GDT head. Also discovered there are 5 variables to enter after a CASIUS calibration. Windows XP entered these value automatically however Windows 7 requires them to be input manually.

February 20, 2013 from DJ Osborne:Just a few minor tweeks to let you know about regarding nav on the Carson. Based on Winfrogs strong suggestion we have added a sound velocity profile in sonardyne. You can turn it off in the environmental page if you have issues or otherwise. BTW, kalman filtering is off on both sonardyne and winfrog. Sonardyne is now available for viewing at the aft steering station on the bridge, left monitor, aux input. You may need to ask the pilots to activate it (alt C) No need for the sonardyne power supply to drive that head all the time when you don't need it on. A third slave for winfrog was added in the dry lab to move towards giving the AUV guys a better set up and to keep them from having to VNC or take trips into the control room. Sonardyne has given the ok for us to put in the offsets we acquired when we did the CASIUS last year. I didn't get a great deal of feedback as to the concerns of our dataset but the results are: Pitch .65, roll 2.09 and heading -.90. The calibration offsets HAVE been entered into Sonardyne from now forward.

Files for Tiburon 2004249 and 250 have been specially altered by Mike McCann using markpoint files.

March 2011: Dave Caress has potentially identified an issue with the software and is working on a new release of MBnavedit. We are still getting un-removable spikes in the navigation files.

March 2011 Western Flyer returned from the shipyard with a new Sonardyne hydrophone; a Cassius calibration occurred on March 4, 2011 (see attached document). Navigation data from the first cruise looks much improved - lak.

April 26, 2010 Doc Ricketts is preparing to change from fusion to ranger software due to support issues.

Flat-line navigation for DOCR 2009299 and 2009309

October 2009: Dave Caress has potentially identified an issue with the software and is working on a new release of MBnavedit. We are still getting un-removable spikes in the navigation files.

Poor navigation data coming from Doc Ricketts (specifically through D0041 on June 19, 2009).

Ventana dives V3443 - 3448 (2009303-2009310) have no usable navigation data. ROV pilots/R. Schramm reduced the NEMA message stream from Winfrog due to sonar interference. The problem was identified during V3448 and corrected about half way through the dive.

Regarding Doc Ricketts (from Rich Schramm 5/8/09): The first few dives had bad pressure from the vehicle. For sure the first 3 dives had major issues and ctd could (should?) be substituted. Then on dives less than about D0014 the parosci had issues if vehicle went past 3267.0 - which it didn't for most of the dives (it did on Smith dives- lak). I don't think SMD has sent a fix for that problem yet but we have a workaround where we intercept the sensor data and fix it before it gets to the vehicle.

April 2009: Dave Caress has released a new version of MBnavedit to a fix for the following problem: based on the nature of specific dives, some navigation spikes cannot be removed.  See V3334, V3335 as examples. We are currently evaluating the new software.

Poor navigation data coming from Doc Ricketts (through D0041 on June 19, 2009).

Historic issues:

1) Between 26 June 2008 and 03 February 2009, there is a roundoff error logged in all raw navigation data files essentially rendering the last 2 digits of latitude and longitude meaningless.The truncation of precision was because of error in the linux port of the datamanager code. The error was identified and fixed on 3 Feb 2009. An analysis of Steve Rock's Ventana dive V3241 (a video mosaic survey) by using data from the winfroglogr files (rov nav input to datamanager) and properly edited data (from the low precision archived nav) indicates that very little improvement in the final edited product can be had by replacing the low precsion nav with nav reprocessed from the winfroglor data.

2) In 2001, there was a navigation "freezing" problem.  This problem occurred from March 25th, 2001 11:59:58 PM through December 14th, 2001 05:10:23 AM.  See John Graybeal's .ppt presentation about this issue (Sept 2001) NavProblemsReview_Graybeal.ppt

3) There was an issue with dives T119 to T244 whereby ships navigation was logging as ROV navigation;  All ROV navigation for these dives is therefore erroneous. See attached excel sheet CompareWflyTibr-Graybeal.xls.

4) Specific to issue #3: As of 12-February 2009, Dave Clague and Jenny Paduan are working with Mike McCann to use the Markpoint files created during dives T119-124, T139-147, T185-201, and T207-208 to produce smoothed navigation files to merge with the video annotations. This series of dives did not have an ROV nav file recorded since ship nav was incorrectly being placed in the ROV nav file. They are going to try to use Markpoint files to reconstruct the ROV path. See attached map for a visual image of the problem and solution.

They are also looking at the navigation of dive T425 with Mike and trying to adjust the track so that it better fits the bathymetry. At present, although the dive plots as starting and ending at the fish trap (located during navigated dive T427), it is not plotting so that depths match with the underlying bathymetry. This is the dive that did not have any USBL navigation because the transponder on the vehicle was not operational.  See attached map for a visual image of the problem and solution.

5) Prior to September 2005, VARS (and earlier VIMS) database queries returned navigation data from the unedited navigation files. 

6) For other problematic individual dives, see this page.

7) There were depth sensor problems between 10/22/12 (yrday 296) and 11/29/12. New raw navigation files were generated, but it was not necessary to re-edit the navigation files.

CompareWflyTibr-Graybeal.xls (application/vnd.ms-excel)
NavProblemsReview_Graybeal.ppt (application/vnd.ms-powerpoint)
NavComparison_2000_Davidson-newEdNav.jpg (image/jpeg)
T425shift.jpg (image/jpeg)
CASIUSReport.pdf (application/pdf)