Driver to decode bottom track forward and starboard ground velocity from an ASCII output data ensemble from an RD Instruments (RDI) Acoustic Doppler Current Profiler (ADCP), using the VmDas NMEA $VDVBW format.
VmDas © RD Instruments (September 2001) is a software package for use with RDI Vessel Mount Acoustic Doppler Current Profilers.
This software package supports the Broadband, Workhorse, and Ocean Surveyor PD0 Binary Output Data Formats for data collection.
The driver returns the horizontal velocity vector along with its direction (heading).
The unit of the speed observation must be selected and set to 'Knots' in Database Setup.
The defined Direction observation (Database Setup) should always be of Type "Angle" (not Bearing, True).
Only data with the status 'A' is decoded and passed to Qinsy.
No special two-way RS-232 cable connection is required.
The driver does not send any command to the Doppler, so the unit should already be in continuous data output mode.
The unit for the Speed observation should be knots, the recommended a priori sd 0.1.
The unit for the Angle observation should be degrees, the recommended a priori sd 5.0.
Drivers IO Notes
The Qinsy RDI driver has the possibility to validate the speed data that is being decoded. To use this feature the user has to manually edit the "DRIVERS.IO" file.
Locate the DrvRDIRemoteCherry.exe driver with the VMDAS cmdline parameter.
Any number behind this parameter that is present as command line argument will be used as the maximum speed to be accepted by the driver. This value must be in knots.