INS for launcher

Inertial Navigation System (INS) withstanding harsh environment
Kassav

Overview

KASSAV 1 (Kit Autonome de Sécurité pour la SAuvergarde en Vol) is an inertial navigation system (INS) dedicated to launchers and used in Ariane 5 since 2020. It is based on iXblue Fiber-Optic Gyroscope (FOG) technology and on iXblue vibrating accelerometers technology.

One of the key element of this INS is its ability to resist vibrations and shock while maintaining performance during take-off and jettisoning . In addition, it withstands vacuum and important temperature variations. KASSAV 1 project demonstrates how robust the FOG technology is.

Specifications

Main features

  • 3 accelerometers, 3 fiber optic gyroscopes, 1 GNSS receiver
  • Dedicated algorithm to hybridize all the sensors and to offer reliable and precise position during take-off
  • Full performances under vibrations (27grms random and 20g sin), shocks, in vacuum and at very high speeds (up to 10 000 m/s)
  • Already in use in Ariane 5

Main performance

  KASSAV 1
PERFORMANCES  
FOG ARW 0.03 °/√h
FOG bias stability at 12 months @ 3s 0.1°/h
FOG scale factor at 12 months @ 3s 300 ppm
Accelerometer bias at 12 months 0.001 g peak
Accelerometer scale factor at 12 months 300 ppm peak
Accelerometer range ± 50g
GNSS Galileo. GPS. Glonass. BeiDou…
Position precision (for all environments and speeds) below 20 m
Alignement duration static below 30 minutes
Bandwidth up to 100 Hz
   
ENVIRONMENT  
Temperature (full performances) '0°C to 50°C
Vibration (full performances) 22g sin and 27 g rms random
Shock (full performances) Up to  5 000 g up to 25 kHz
Vacuum (full performances) withstands space vacuum
   
MECHANICAL INTERFACE  
Mass 3.85 kg
Volume HLW = 157 mm x 334 mm x 184 mm
   
ELECTRICAL INTERFACE  
Power bus 20 V to 34 V
Communication

RS 232 and RS422

Power  18 W

 

Applications