INSSTDEV

INS PVA standard deviations

Platform: 

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

This log displays the INS PVA standard deviations.

Message ID: 2051

Log Type: Synch

Abbreviated ASCII Syntax:

log insstdev ontime 1

ASCII Example:

#INSSTDEVA,USB1,0,66.0,FINESTEERING,2209,491004.000,02000020,2396,16809;0.1813,0.1813,0.1806,0.0018,0.0018,0.0017,0.0292,0.0291,0.0577,13000045,0,0,7fd1bf,0*b490ddee

Field

Field Type

Description

Binary Format

Binary Bytes

Binary Offset

1

Log header

INSSTDEV header

For information about log headers, see ASCII, Abbreviated ASCII or Binary.

-

H

0

2

Latitude σ

Latitude standard deviation (m)

Float

4

H

3

Longitude σ

Longitude standard deviation (m)

Float

4

H+4

4

Height σ

Height standard deviation (m)

Float

4

H+8

5

North Velocity σ

North velocity standard deviation (m/s)

Float

4

H+12

6

East Velocity σ

East velocity standard deviation (m/s)

Float

4

H+16

7

Up Velocity σ

Up velocity standard deviation (m/s)

Float

4

H+20

8

Roll σ

Roll standard deviation (degrees)

Float

4

H+24

9

Pitch σ

Pitch standard deviation (degrees)

Float

4

H+28

10

Azimuth σ

Azimuth standard deviation (degrees)

Float

4

H+32

11

Ext sol stat

Extended solution status

See Table: Extended Solution Status

Ulong

4

H+36

12

Time Since Update

Elapsed time since the last ZUPT or position update (seconds)

Ushort

2

H+40

13

Reserved

Ushort

2

H+42

14

Reserved

Ulong

4

H+44

15

Reserved

Ulong

4

H+48

16

xxxx

32-bit CRC (ASCII and Binary only).

Hex

4

H+52

17

[CR][LF]

Sentence terminator (ASCII only).

-

-

-

The INS standard deviation values reported by the SPAN filter are an estimate of the Inertial filter solution quality. In lower accuracy GNSS position modes, such as SINGLE or WAAS (see Table: Position or Velocity Type), the position standard deviation values can appear to become optimistic compared with the absolute GNSS accuracy. This is due to the INS filter’s ability to smooth short term noise in the GNSS solution, although the overall position error envelope still reflects the GNSS accuracy. Therefore, if the desired application requires absolute GNSS position accuracy, it is recommended to also monitor GNSS position messages such as BESTGNSSPOS (see BESTGNSSPOS log).