RLG SIGMA 40 is an inertial navigation system which is based on Ring laser gyro technology. This system has state of the art technology which is completely advanced and rugged. This system has been designed by Sagem specially for Navy applications and it fulfills most demanding navigation criteria and weapon stabilization requirements.

It provides all the critical navigational data like heading, roll and pitch, angular velocities, position and heave, horizontal/vertical velocities and accelerations.

RLG SIGMA 40 consists an Inertial Navigation Unit (INU), a Control and Display Unit (CDU) and an Installation Support (SDI) enabling quick assembly and disassembly without any alterations/adjustments. This RLG sigma 40 is upgradable and is quite easy to install, maintain and operate.

 The main features of RLG Sigma 40 are :

  • It has got high-level performance
  • It has very simple installation requirements
  • It has very convenient operation procedure.
  • It does not requires any preventive maintenance.
  • It consists both Synchro and digital interfaces. There is no need to provide any extra hardware interface.
  • It is IMO approved and military standards certified.
  • It is very reliable and rugged.

The core aim of RLG sigma 40 is :

  • To provide the target navigational data like heading, roll, itch etc in real time.
  • To regularly update the target navigational data like speed and velocity.
  • Interfacing of other navigational inputs from/to other Navigational equipments like EM Log, GPS, DGPS, Radar, Anemometer etc.

Sub-Units of RLG Sigma 40:

The RLG Sigma 40 system contains four basic sub-units. They are as follows:

Components of Ring Laser Gyro Sigma 40

Components of Ring Laser Gyro Sigma 40

Here,  INU stands for Inertial Navigation Unit

            CDU stands for Control and Display Unit

            DDU stands for Data distribution unit, and

            UPS stands for Uninterrupted Power Supply

The Inertial Navigation Unit of basic RLG Sigma 40 unit consists of the following sub-units:

  • Inertial Sensor Block (referred as BSI)
  • Basic Synchro Module
  • EB Module
  • UTR-SP Module
  • Interface module (or RS 422 Module)
  • Power Supply Unit
  • HT/ THT Module
Composition of Inertial Navigation Unit

Composition of Inertial Navigation Unit

The Inertial Sensor Block (BSI) consists of the various sensors. They are :

  1. Laser Gyros (Model GL S32) 03 in numbers : It senses Angle of Rotation and Speed of Rotation.
  2. Accelerometers (Model A-600)   : It senses the acceleration.
  3. EACC : It consists the circuitry for controlling the Pendulum of Accelerometer using servo elements. In addition to that, It also contains the EEPROMs which stores the sensor’s calibration data.

** EEPROM stands for Electrically Erasable Programmable Read Only Memory.