The Tritech iFG (Intelligent Fibre-Optic Gyro) provides additional heading stability when combined with the Tritech Intelligent Gyro Compass (iGC), or other heading and motion reference units (MRUs).

The iFG uses a single-axis FOG sensor, mounted inside an extruded aluminum housing and can typically reduce heading drift errors more effectively than most magnetically referenced aircraft gyros.

An on-board processor manages the FOG sensor interface, mode selection, power supplies and water ingress sensing (for use if the iFG is mounted inside its own pod). The iFG provides internal compensation for pitch and roll angles using data from the iGC attitude sensors.

The iFG receives magnetic heading and pitch and roll data from the iGC; using proprietary slaving algorithims, it then provides an output of stabilised heading with low drift rate. Output data is transmitted to the 3 serial ports provided.

Additional (external) interface cards are available when an iGC/ iFG is fitted to existing ROVs to replace a mechanical gyro compass. This provides specific communication protocol compatibility and analogue (autopilot) functionality.