POS MV V5 Installation and Operation Guide
TrueHeave
Operation
Copyright © Applanix Corporation, 2017
6-1
6.0 TrueHeave Operation
Overview
TrueHeave
TM
provides an estimate of vessel heave during conditions that often defeat traditional real-time
heave filters. The POS MV TrueHeave solution uses algorithms that provide a zero phase response
across the range of 0.03 to 0.2 Hz (30 to 5 s). Traditional real-time heave solutions tend to exhibit their
most notable artefacts in long (>16 s) period swell conditions, often encountered with vessels in following
seas. The frequency range of the TrueHeave solution dramatically reduces such low frequency artefacts.
Figure 52 illustrates the relationship of the TrueHeave solution to the current real-time approach and
shows how it is computed and applied.
Figure 52: TrueHeave Functional Block Diagram
Configuration Requirements
TrueHeave is a turnkey solution and requires none of the tuning of standard real-time heave solutions.
Initialization Requirements
TrueHeave requires a period of up to five minutes after the commencement of navigation in order to
initialize. After this initial period, no further initialization or settling time is required.
Data Output
The TrueHeave solution is provided at the Ethernet interface, LAN port. Details of the output message
format are provided in the POS MV V5 User Interface Control Document (Applanix document control
number - PUBS-ICD-004089). This delayed output is provided by the Group 111 heave data message