Figure 81: Example Of Ins Navigation On A Spherical Earth - Applanix POS MV V5 Installation And Operation Manual

In Figure 81, the vessel that supports the INS has no applied angles of roll or pitch, and moves along a
fixed northerly heading.
Ideally, the INS platform defines a navigation frame that is both locally stable and locally level:
• A locally stable reference frame always maintains a constant orientation relative to the surface of
the Earth at its current position.
• A locally level reference frame is always level relative to the surface of the Earth at its current
position.
In Figure 81, the navigation frame of the vessel coincides with the geographic frame of reference.
Inertial Navigation Frames of Reference
This appendix refers to a number of different frames of reference:
• Inertial frame
• Earth frame
• Geographic navigation frame
• Body frame
• IMU body frame
For clarity, the following subsections define each of these reference frames as they apply throughout this
appendix.
Copyright © Applanix Corporation, 2017
POS MV V5 Installation and Operation Guide

Figure 81: Example of INS Navigation on a Spherical Earth

Theory
of Operation
B-5