SETINITAZIMUTH

Set Initial Azimuth and Standard Deviation

Platform:

OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7-S

Use this command to start SPAN operation with a previously known azimuth. Azimuth is the weakest component of a coarse alignment and is also the easiest to know from an external source (i.e., like the azimuth of roadway). When using this command, SPAN operation through alignment will appear the same as with a usual coarse alignment. Roll and pitch is determined using averaged gyro and accelerometer measurements. The input azimuth is used rather than what is computed by the normal coarse alignment routine.

• Input azimuth values must be accurate for good system performance.

• Sending SETINITAZIMUTH resets the SPAN filter. Following realignment, vehicle dynamics are required for the filter to re-converge. Bridging performance is poor before filter convergence.

• The entered azimuth angle is with respect to the configured output frame. This is generally the vehicle frame unless a User Frame offset has been configured using the SETINSROTATION command. All offsets should be entered before entering the SETINITAZIMUTH command.

• This command is not save configurable and must be re-entered after each start-up. The command can be entered at any time and will be used automatically when the system is ready to begin alignment.

Azimuth is positive in a clockwise direction when looking towards the z-axis origin.

Message ID: 863

Abbreviated ASCII Syntax:

SETINITAZIMUTH azimuth azSTD

Abbreviated ASCII Example:

SETINITAZIMUTH 90 5

Field	Field Type	ASCII Value	Binary Value	Description	Binary Format	Binary Bytes	Binary Offset
1	Command header	-	-	SETINITAZIMUTH header This field contains the command name for abbreviated ASCII or the message header for ASCII (see page 1) or Binary (see page 1).	-	H	0
2	azimuth	0 to 360		Input azimuth angle (degrees)	Double	8	H
3	azSTD	1 to 25		Input azimuth standard deviation angle (degrees)	Float	4	H+8