June 2017
Document 1000-4126 - FSM300 Tare Function Usage Guide - Revision 1.1
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FSM300
Tare Function Usage Guide
Introduction
This document describes the Tare function of the FSM300 that redefines the orientation of the sensor.
This allows the outputs of the FSM300 to be in line with the orientation with which it was mounted into
the main device. These commands are described in more detail in the SH-2 Reference Manual
[1]
and
this document assumes that the reader has this manual available for reference.
Tare Overview
The FSM300 uses two commands and a configuration record to redefine the sensor’s orientation, or
“Tare”:
-
Commands:
o
Tare Now (Section 6.4.4.1 of SH-2 Reference Manual)
§
Allows for a temporary Tare. Useful at the start of a game to define the current
orientation.
o
Persist Tare (Section 6.4.4.2 of SH-2 Reference Manual)
§
Saves the current Tare orientation into the Sensor Orientation configuration
record. This is a persistent setting that now becomes the default orientation.
-
Configuration Record
o
Sensor Orientation
§
Stores the orientation of the device. Once you know the standard orientation of
your FSM300 in your device, you can use the same starting orientation for all
devices using this record as a convenient starting point. More accurate per-
device taring can be done using the commands above.
Tare Options
There are two options that you can choose from when running a Tare operation:
-
Axes
o
Which axes do you want to tare across? For instance, you can choose to only tare on
yaw (Z-axis) which will reset the heading to the user’s current forward orientation. Or
you can tare across all axes (resets heading, pitch and roll).
-
Rotation Vector to use as basis for Tare (Rotation Vector, Game Rotation Vector, Geomagnetic
Rotation Vector)
o
The FSM300 offers three different types of Rotation Vector outputs that define the
orientation of the module using different inputs. Refer to the SH-2 Reference Manual
for more details about these three rotation vector options.
