$DVPDL and $DVPDX: DVL Position and Angle Deltas Messages

The $DVPDL/X messages supply odometry data intended for use in user-supplied dead reckoning or in user-built position-hold functions. It is output at a variable rate between 5Hz and 20 Hz. The $DVPDX message is the same as a $DVPDL message with a few extra fields tacked onto the end.

The Position Deltas X, Y and Z are in the vehicle coordinate frame as modified by the SET-SENSOR-ORIENTATION command.

The Pitch and Roll data and the standoff datum are in the sensor coordinate system and are not influenced by the SET-SENSOR-ORIENTATION command.

Format:

$DVPDL,tu,dtu,adr,adp,ady,pdx,pdy,pdz,c*hh

$DVPDX,tu,dtu,adr,adp,ady,pdx,pdy,pdz,c,mode,pitch,roll,stdoff*hh

Example:

$DVPDL,101234000,50000,0.001263,-0.019663,-0.745226,-0.000,0.001,-0.005,100*22

Field	Name	DVL Notes
tu	Time uSec	Time since system boot in microseconds
dtu	Delta Time uSec	Time since the last message, in microseconds
adr	Angle Delta Roll	Angle delta from previous message, in radians. Always 0 for Tracker 650.
adp	Angle Delta Pitch	Angle delta from previous message, in radians. Always 0 for Tracker 650.
ady	Angle Delta Yaw	Angle delta from previous message, in radians. Always 0 for Tracker 650.
pdx	Position Delta X	Position delta from previous message, in meters
pdy	Position Delta Y	Position delta from previous message, in meters
pdz	Position Delta Z	Position delta from previous message, in meters
c	Confidence	0..100, where 100 = maximum confidence, 0 = no confidence. If 0, assume all other fields after dtu are garbage.
mode	System Mode	Used by Cerulean for diagnostic purposes
pitch	Pitch	Rotation of the sensor head around the Y axis, with respect to the target plane, in degrees. Parallel = 0. Right-hand rule.
roll	Roll	Rotation of the sensor head around the X axis, with respect to the target plane, in degrees. Parallel = 0. Right-hand rule.
stdoff	Standoff	Distance between sensor head and target plane along a normal to the target plane, in meters.
*	End of fields
hh	Checksum	NMEA standard