Version 5 (modified by knpa, 5 years ago) (diff)


GRIMM Sky OPC internal/processing

Data output

The data comes out of the plane in two different ways:

  • A csv file created by phil's script that runs during flight: ~arsf/code/external_code/ops/ This is described in the main Grimm section
  • A binary file from DustMonitor (GRIMMs software)

The DustMonitor files comes in .dm and .di pairs (measurements and metadata respectively). There should also be a _nav file.

The software can run in two modes - particle count or mean mass.

If you collect in particle count, you can later convert to mean mass BUT NOT THE OTHER WAY AROUND.

To view the data, you'll have to load it into DustMonitor, at which point you can write out a csv file.


Software is located at ~arsf/backups/windows_software/grimm/Grimm_Software_ISO/

Think it needs to run on xp. Is installed on the Windows machine. You need to make sure that the input files have "Read Only" unchecked before loading them (there's no error that tells you this, it just doesn't work).

Once it's loaded, you can look at the overview/table/graph. You can change how it is displayed using the control panel at the bottom.

Output to an ascii/csv file with file -> export

The format of the data exported is not controlled by the control panel. It is determined by the settings under Options -> Graph -> Calculation. You can use this to change between accumulative/differential, real values/percent relation, and pick the units.

Grimm Spectrometer

To convert a particle count .dm to a mean mass one, you can use Grimm Spectrometer (not tested). This is under ~arsf/backups/windows_software/grimm/GRIMM_Spectrometer_2-5-4_Setup_FullPackage.exe

The GRIMM output from the spectrometer has a timestamp but no positional information. knpa has written a script to use the timestamps to append position info from the ARSF navigation files: ~arsf/usr/opt/grimm/

Usage: <comma_sep_grimm> <grimm_nav_file> <sol_file>

The grimm_nav_file is the nav file that is automatically output by DustMonitor in-flight. The sol_file is the ARSF post-processed nav file. The latter is used first, with the grimm nav file only being used when the sol file lacks coverage (which often occurs at the start or end).

Other tools

knpa has also written a script to identify periods where the plane is ascending or descending so as to extract vertical profiles: /users/rsg/arsf/usr/opt/grimm/

Usage: <grimm_file> [-p]

Extracts vertical profiles with stats describing the min/max values. -p argument to print rather than write to a file.