DMU380ZA Series
User’s Manual
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Doc# 7430-3810 Rev.02
Page 25
iron and soft iron effects to avoid any system performance degradation. See section 3.4.1
for information and tips regarding installation and calibration and why magnetic
calibration is necessary. Please review this section of the manual before proceeding to use
the INS380ZA.
IMPORTANT
For optimal performance the INS380ZA utilizes GPS readings from an external GPS
receiver. The GPS receiver requires proper antennae installation for operation. See
section 2.1.4 for information and tips regarding antenna installation.
3.5.1
INS380ZA Magnetometer Calibration and Alignment
The INS380ZA requires the three axis magnetic field sensor to be calibrated while
installed in its operating environment. See section 3.4.1 for information and tips
regarding installation and calibration and why magnetic calibration is necessary. Please
review this section of the manual before proceeding to use the INS380ZA.
3.5.2
INS380ZA Advanced Settings
In addition to the configurable baud rate, packet rate, axis orientation, and sensor low-
pass filter settings, the INS380ZA provides additional advanced settings which are
selectable for tailoring the INS380ZA to a specific application requirements. The
INS380ZA advanced settings are shown in Table 12 below:
Table 12 INS380ZA Series Advanced Settings
Setting
Default Comments
Baud Rate
38,400
baud
9600, 19200, 57600 also available
Packet Type
N1
S0, S1, A1, A2, N0 also available
Packet Rate
25 Hz
This setting sets the rate at which selected Packet Type, packets are output. If polled
mode is desired, then select Quiet. If Quiet is selected, the INS380ZA will only send
measurement packets in response to GP commands.
Orientation
To configure the axis orientation, select the desired measurement for each axes; NAV-
VIEW will show the corresponding image of the INS380ZA, so it easy to visualize the
mode of operation. See section 8.4 Orientation Field settings for the twenty four possible
orientation settings. The default setting points the connector AFT.
Filter Settings
20 Hz
accels
20 Hz
rates
The low pass filters are set to a default of 20Hz for the accelerometers, and 20Hz for the
angular rate sensors. There is one filter setting for all three angular rate sensors. There is
one filter setting for all three accelerometer sensors. The reason for filtering the
accelerometers is that in many installations, the vibration level can be high, and it can
prove helpful to filter accelerometers.
Freely Integrate
OFF
The Freely Integrate setting allows a user to turn the INS380ZA
into a ‘free gyro’.
In free
gyro mode, the roll, pitch and yaw are computed exclusively from angular rate with no
kalman filter based corrections of roll, pitch, and yaw. When turned on, there is no
coupling of acceleration based signals into the roll and pitch or magnetometer based
signal to the yaw. As a result, the roll, pitch, and yaw outputs will drift roughly linearly with
time due to sensor bias. For best performance, the Freely Integrate mode should be
used after the algorithm has initialized. This allows the Kalman Filter to estimate the roll
and pitch rate sensor bias prior to entering the free gyro mode.
Upon exiting the ‘free
gyro’ mode
(OFF), one of two behaviors will occur
(1)
If the INS380ZA has been in freely integrate mode for less than sixty seconds,
