Xsens Technologies B.V. AW-A Benutzerhandbuch
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Parameter
Description
Line
The sync line to activate.
Polarity
Positive pulse (where the polarity is initially low [0V] and goes high
[3.3V]).
Negative pulse (where polarity is initially high [3.3V] and goes low
[0V]).
[3.3V]).
Negative pulse (where polarity is initially high [3.3V] and goes low
[0V]).
Trigger Once
It is not recommended to selected Trigger once, if more than one
recording using synchronisation of multiple systems will be made.
recording using synchronisation of multiple systems will be made.
Skip First
Number of initial sync pulses to skip. This command is useful if a well-
defined delay is expected between the Xsens and the third party
system. It may also be needed if the third party, like the Xsens system
uses the same pulse properties to trigger different actions. See
description provided above for Sync In.
defined delay is expected between the Xsens and the third party
system. It may also be needed if the third party, like the Xsens system
uses the same pulse properties to trigger different actions. See
description provided above for Sync In.
Skip Factor
Number of sync pulses, between the sync pulses delivered, to skip. See
Sync In Table description.
Sync In Table description.
Pulse Width
Some systems wait for a signal of a minimum pulse width before
generating the desired synchronisation action. The Awinda Station can
send a pulse with a duration of up to 99ms to a third party system. It is
not recommended to send a signal longer than a frame width.
Specify 0 ms to generate an infinite pulse width.
generating the desired synchronisation action. The Awinda Station can
send a pulse with a duration of up to 99ms to a third party system. It is
not recommended to send a signal longer than a frame width.
Specify 0 ms to generate an infinite pulse width.
6.8 Orientation Reset
In some situations, it may occur that the MTw sensor axes are not exactly aligned with the
axes of the object of which the orientation has to be recorded. It may be desired to output
the orientation and/or calibrated inertial (and magnetic) data in an object-fixed frame, as
opposed to a sensor-fixed frame. Four methods have been added to the software to
facilitate in obtaining the output in the desired coordinate frames.
1. Setting an arbitrary rotation matrix to rotate S to the chosen object coordinate system
axes of the object of which the orientation has to be recorded. It may be desired to output
the orientation and/or calibrated inertial (and magnetic) data in an object-fixed frame, as
opposed to a sensor-fixed frame. Four methods have been added to the software to
facilitate in obtaining the output in the desired coordinate frames.
1. Setting an arbitrary rotation matrix to rotate S to the chosen object coordinate system
O. See Section 11.6.3.
2. A heading reset that redefines the X-axis of the global coordinate frame while
maintaining the Z-axis along the vertical (also known as “boresighting”). After the
heading reset the orientation will be expressed with respect to the new global (earth
fixed) reference frame. See Section 11.6.4
heading reset the orientation will be expressed with respect to the new global (earth
fixed) reference frame. See Section 11.6.4
3. An object reset that defines how the MTw is oriented with respect to the coordinate
axes to which it is attached. After the object reset, both the inertial (and magnetic) and
orientation data are expressed with respect to the axes of the object. See Section 11.6.5.
orientation data are expressed with respect to the axes of the object. See Section 11.6.5.
4. A combined object/heading reset, referred to as alignment. See Section 11.6.6.
NOTE: For all co-ordinate system reset functions it is important to remember that the
housing of the MTw cannot be considered an accurate reference. Placement and subsequent
aligning must be done very carefully otherwise (alignment) errors may be induced.
NOTE: For all co-ordinate system reset functions it is important to remember that the
housing of the MTw cannot be considered an accurate reference. Placement and subsequent
aligning must be done very carefully otherwise (alignment) errors may be induced.