NORSUB6g | norwegian-subsea

The NORSUB6g protocol is a proprietary communication standard with an NMEA-based format, designed to store the data listed below. Note that NORSUB6g includes gravity in the z-axis acceleration measurement.

Data:

Roll, pitch, heading
Surge, sway, heave
Roll rate, pitch rate, yaw rate
Surge velocity, sway velocity, heave velocity
x acceleration, y acceleration, z acceleration (including gravity)

Format:

$PNORSUB6,T1,T2,roll,pitch,heading,surge,sway,heave,roll_rate,pitch_rate, yaw_rate,surge_vel,sway_vel, heave_vel,acc_x,acc_y,acc_zG,status*CS<CR><LF>

NORSUB6g protocol description
FIELD N.	FIELD	DESCRIPTION	UNIT	TYPE	NOTE
0	$PNORSUB6	identifier	-	string	Telegram identifier.
1	T1	time for valid measurement (internal clock)	[us]	uint32	Can store values from 0 to (2^32-1).
2	T2	delay from T1 to telegram is sent	[us]	uint32	Can store values from 0 to (2^32-1).
3	roll	roll angle	[deg]	DBL (%.4f)	Floating-point number with four decimal places.
4	pitch	pitch angle	[deg]	DBL (%.4f)	Floating-point number with four decimal places.
5	heading	heading angle	[deg]	DBL (%.4f)	Floating-point number with four decimal places. Range: [0.001 - 359.9999].
6	surge	surge	[m]	DBL (%.4f)	Floating-point number with four decimal places.
7	sway	sway	[m]	DBL (%.4f)	Floating-point number with four decimal places.
8	heave	heave	[m]	DBL (%.4f)	Floating-point number with four decimal places. Sign: Positive (+) when z-down.
9	roll_rate	roll rate	[deg/s]	DBL (%.4f)	Floating-point number with four decimal places.
10	pitch_rate	pitch rate	[deg/s]	DBL (%.4f)	Floating-point number with four decimal places.
11	yaw_rate	yaw rate	[deg/s]	DBL (%.4f)	Floating-point number with four decimal places.
12	surge_vel	surge velocity	[m/s]	DBL (%.4f)	Floating-point number with four decimal places.
13	sway_vel	sway velocity	[m/s]	DBL (%.4f)	Floating-point number with four decimal places.
14	heave_vel	heave velocity	[m/s]	DBL (%.4f)	Floating-point number with four decimal places. Sign: Positive (+) when z-down.
15	acc_x	acceleration x	[m/s²]	DBL (%.5f)	Floating-point number with five decimal places.
16	acc_y	acceleration y	[m/s²]	DBL (%.5f)	Floating-point number with five decimal places.
17	acc_zG	acceleration z incl. g	[m/s²]	DBL (%.5f)	Floating-point number with five decimal places.
18	status	full status message	-	uint32	1: OK, 0: error. See health monitoring system for more details.
19	CS	NMEA checksum	-	HEX	XOR of characters between $ and *

Example:

NORSUB6 frame with raw example data is listed below.

$PNORSUB6,735924181,7566,0.188,0.447,357.132,0.012,-0.002,-0.001,-0.000, -0.000,0.003,0.012,0.003,-0.002,0.07679,-0.04408,-9.83225,1*71<CR><LF>

Field 0	Field 1	Field 2	Field 3	Field 4	Field 5	Field 6	Field 7	Field 8	Field 9	Field 10	Field 11	Field 12	Field 13	Field 14	Field 15	Field 16	Field 17	Field 18	Field 19
$PNORSUB6	735924181	7566	0.188	0.447	357.132	0.012	-0.002	-0.001	-0.002	-0.002	0.003	0.012	0.003	-0.002	0.07679	-0.04408	-9.83225	1	71

Decoded values:

T1
- Raw value: 735924181, decoded time: 735924.181 seconds.
T2
- Raw value: 7566, decoded time: 7.566 seconds.
roll
- Raw value: 0.188, decoded roll angle: 0.188 degrees.
pitch
- Raw value: 0.447, decoded pitch angle: 0.447 degrees.
heading
- Raw value: 357.132, decoded heading angle: 357.132 degrees.
heave
- Raw value: 0.012, decoded heave: 0.012 m.
roll rate
- Raw value: -0.002, decoded roll rate: -0.002 deg/s.
pitch rate
- Raw value: -0.001, decoded pitch rate: -0.001 deg/s.
yaw rate
- Raw value: -0.002, decoded yaw rate: -0.002 deg/s.
surge velocity
- Raw value: -0.002, decoded surge velocity: -0.002 m/s.
sway velocity
- Raw value: 0.003, decoded surge velocity: 0.003 m/s.
heave velocity
- Raw value: 0.012, decoded heave velocity: 0.0012 m/s.
acceleration x
- Raw value: 0.003, decoded acc x: 0.003 m/s².
acceleration y
- Raw value: -0.002, decoded acc y: -0.002 m/s².
acceleration z
- Raw value: 0.07679, decoded acc z: -9.83225 m/s².
status
- Raw value: 1, decoded status: OK.
checksum:
- Created from XOR operations of characters between $ and * in the example frame.

Note

Unlike industry standards, the NORSUB6g protocol has a fixed reference frame for data (e.g., heave). However, the data's location (e.g., MRU or MP1) remains configurable.