System; Imu; Ekinox Imu; Accelerometers - SBG Navsight Ekinox IMU Hardware Manual

Navsight Solution – Hardware Manual

2.1. System

The following diagram shows the basic organization of the Navsight solution. Internal GNSS receiver is
optional.
The RS-485 link between IMU and processing unit allows secure and long distance communication (eg
50m).

IMU

3 Axis
Gyroscopes
3 Axis

Accelerometers

2.2. IMU
The IMU is the main component that will drive the overall system performance. Several IMU configurations
are proposed to address different applications requirements.

2.2.1. Ekinox IMU

Ekinox IMU has been designed to deliver an exceptional performance in a very compact and cost effective
package. Ekinox IMU integrates low noise gyroscopes. The integrated accelerometers are ultra low noise and
highly efficient in vibrating environments due to a low Vibration Rectification Error. Sensor specifications
are listed below.
2.2.1.1. Accelerometers
Full scale ( g )
Velocity Random Walk (µ g /√hz)
In run bias instability (µ g )
Vibration Rectification Error (µ g / g ²)
Bandwidth (Hz)
Orthogonality (°)
Sensors sampling &
Calibration
Coning & Sculling
integrals @ 1 kHz
Figure 2.2: Navsight simplified block diagram
A2
± 8
7
2
<200
433
< 0.02
Processing Unit
EKF and output
RS-485
@ 200 Hz
Aiding Equipment
Dual Antenna GPS, GPS/GNSS, RTK
»
Odometer, DVL
»
A3 Remarks
± 14
40 Allan variance – @ 25°C
10 Allan variance – @ 25°C
<50 VRE – 20 Hz – 2 kHz
433 Attenuation of 3 dB
< 0.02 Over temperature range
9/74
NAVSIGHTHM.1.3
CAN
RS-232/422
ETHERNET
GNSS*