Add Binary Navigation Files option of the Source menu in the Main Menu bar.
What it does
The Navigation Import Configuration dialog is for importing navigation data logged or processed with third party software. See Position and Motion Formats for supported data types.
General Description
The dialog has several sections, these are explained below.
POSPac Data
When importing POSPac SBET files, 'sbet' must be part of the base name of the file. The base name is the part of the file path preceding the extension and after the directory.
Applanix's POSPac creates SBETs which can also have an associated RMS file. This RMS file contains standard deviation information that Qimera can then use and display. This file is however not necessary in order to process the SBET into imported data.
Qimera will automatically search for the SBET's associated RMS file. If the RMS file is not found Qimera will inform the user within the Job Activity Dock.
Example of message in Job Activity Dock: "Info: No matching RMS file found for: **SBET FILE NAME"
If you have an associated RMS file, it must have the same naming except that 'sbet' is replaced with 'smrmsg' (and it must reside in the same directory). If this naming convention is not used, Qimera will not be able to auto-recognize the file type.
Vessel
Navigation data must be attached to a vessel. Simply select the vessel from the dropdown for which the navigation is being imported.
Position, Motion, Depth and Pressure System Reference
All imported navigation data must be attached to a new system. If you have not imported navigation data previously in the project you will need to create new systems for import data types. Otherwise you can use previously configured systems. After systems are created they can be further modified in the Qimera Vessel Editor.
Creating a new System
To create a new system click the button next to the system drop down.
After reviewing and accepting values in the New System dialog the new system should be shown in the dropdown. Check the data types that are to be extracted into the system.
or
Using an existing system
If you previously imported ASCII data the systems created during the import will be listed in the System drop down. Simply select the appropriate system and check the import data types.
Using an existing systems means all settings will be identical. If different uncertainty or offset settings for the system may be needed it is advisable to create a new system with copied settings.
Importing an SBET as a depth
If a depth system is created, the option exists to import the SBET as a depth system instead of a height. Only one of the height & depth checkboxes can be checked at the same time. The vertical value in the SBET will have any model shifts applied (just like the heights would be) and will be usable as a platform depth instead of a height. Just like heights, the depth must be brought in with the position so model shifts can be applied.
If the priority checkbox is checked, the following settings will be changed automatically:
the Vertical Referencing Method for the applicable lines will be set to Tide
the new system will be added to the top of the list in the Depth Source Priorities.
These settings are in the Processing Settings dialog.
Priority
When checked this option will make the imported systems take the highest priority in the Processing Settings Dialog.
This option is checked by default.
For formats that have depth and pressure observations, such as Kongsberg NavLab, depth will alway take the highest priority. If pressure is desired to be highest priority, you will need to uncheck the Depth Source Priorities in the Processing Settings Dialog.
Acquisition Date Reference
For formats that use relative time references, such as POSPac and POSMV, an absolute time reference is needed. The time is stored as GPS seconds-of-week so the week in which the data was logged is needed.
The GPS Week dropdown shows a calendar date picker. The date-selector also accepts inputs via keyboard hot-keys and numeric keystrokes. The hotkeys for moving between yyyy , mm , dd are tab or ctrl+right , shift+tab or ctrl+left. The hotkeys for moving within the yyyymmdd are left, right. The hotkeys for changing the values are up and down
Pick the Sunday of the week during which the data was collected.
Based on the picked week the computed start of the earliest file being imported will be shown below the dropdown.
For formats that store the full time reference, such as Kongsberg NavLab, SRH (PFreeHeave), SBTC and SBIC, the Acquisition Date Reference will only show the Start of File and Day of Year for reference. No need to pick the GPS Week.
SBTC note: SBTC navigation files are in GPS time. Qimera uses a lookup table to compute the number of leap seconds between UTC and GPS time. If the table is not up to date, a positional data shift may be noticeable in the surface.
To fix this shift, the user can apply a latency value of 1 second in the vessel editor and re-nav the source files. This latency value should be applied to the new Position and Motion Systems created upon import of the binary navigation.
Acquisition Coordinate System
Specify the datum of the data being imported. Navigation data will be converted to the project datum specified in the Project Properties Dialog.
Transform heights to Project Coordinate System
This is checked by default. If unchecked the heights with have no geodetic transform applied and thus be referenced to the Acquisition Coordinate System.
Delayed True Z and True Heave
When importing from an Applanix POSMV file, you have the additional option of importing Delayed True Z or True Heave. The True Z import requires logging group 114 (True Z and True Tide data) during acquisition, while the true heave import requires the logging of group 111 (Heave and True Heave data).
Delayed Heave
When importing from a Kongsberg PFreeHeave (SRH) file, you have the option of importing PFreeHeave if the appropriate packet is looged to the file.
