Somat eDAQlite, Руководство пользователя

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Somat eDAQ
lite
98 I2773-4.
4
en
use with an external GPS antenna and a TNC connection that allows for external
triggering. The receiver has a serial interface connection routed to the ELDIO or
ELCOM.
Another feature available with the EGPS-200 receiver is GPS-based master sample
rate clock generation. Use the configuration options of the parent layer (ELDIO or
ELCOM) to enable GPS clock generation.
5.8.1 Available Inputs
GPS
The EGPS-200 is available in a base model or PLUS package. The base model
provides 22 possible channels including high-accuracy 200 Hz velocity, 20 Hz GPS
speed and absolute position and three-axis instantaneous acceleration. The PLUS
package provides all the channels of the base model plus IMU (inertial measurement
unit) and RTK (real time kinematic) measurement options. The IMU option allows for
extremely high-accuracy three-axis accelerations and rotational rates. The RTK option
uses the readings from two GPS antennas to output high-accuracy yaw, pitch and slip
angle measurements at 20 Hz. The EGPS-200 directly measures the yaw and pitch at
any time, while the slip angle calculations require the vehicle to be moving. For more
information on setting up GPS inputs, see
“Bus-Oriented Input Channels” on
page 121 .
NOTE
Position accuracy varies with several factors including, but not limited to, GPS receiver
configuration, location (geographic latitude, as it influences HDOP, and surrounding
objects possibly blocking reception or causing multi-path reception), satellite
constellation status and ionosphere conditions.
NOTE
There is an anomaly in the acquisition or processing of the GPS time that results in
some small discontinuities in the absolute GPS time data. This occurs when the “nsec”
channel rolls over and persists for about 20% of the time until the “nsec” channel rolls
over again (which takes about 4 hours). As such, there is at least one second of
uncertainty in the GPS time data stored in the data file whether or not the “nsec”
channel is stored.
5.8.2 Configuration Options
Hardware Interface
Select the desired GPS hardware interface.
Databases
Select one or more database files from the presented list. The selected databases
determine the channel types available when adding a GPS channel to the test setup.
HBM: public