Fibre optic rotary joints for miltary vehicles

Edited by the Engineeringtalk editorial team Jan 31, 2002

When the Canadian Army were upgrading the communications system in the Coyote Light Armoured Vehicle, they selected a multimode single pass fibre optic rotary joint to replace a slip ring

When the Canadian Army were upgrading the communications system in the Coyote Light Armoured Vehicle, they selected the Model 197 multimode fibre optic joint from leading supplier Focal Electronics, represented in the UK by IDM Electronics.

The joint was used to replace an existing electrical slip ring as part of a system upgrade for the Surveillance Operators Suite.

The Model 197 is a high performance, multimode single pass fibre optic rotary joint that allows the transfer of optical signals across a rotary interface.

Equipment for combat vehicles needs to be rugged, reliable and manufactured to the highest standards.

Focal fibre optic joints provide a high bandwidth interface for the rotating turret that allows large amounts of data to be transmitted across a rotating interface with high accuracy.

The Model 197 is rugged, compact, completely passive and immune to EMI corruption.

Because fibre optic joints do not carry any electrical signals they are a low spark hazard - an important consideration for a combat vehicle.

The Coyote is in service with the Reconnaissance Squadrons of Canada's armoured regiments and also serves in the Direct Fire Support Squadrons.

There are 203 Coyotes currently in service with Canada's Land Force.

The most innovative aspect of the Coyote is its surveillance system designed to detect hostile forces using a combination of day camera, radar, thermal imaging, and laser range finding equipment.

A mast-equipped version of the vehicle raises its surveillance gear 10 metres above the ground to see hostile forces over obstacles and from protected positions.

Fibre Optic Rotary Joints (FORJ) are available in a variety of different styles to suit the application.

The Model 197 is a single channel design that uses coaxial, opposed fibres, terminated with lenses.

One of the fibre to lens assemblies is allowed to rotate using a suitable bearing configuration, whilst the other remains stationary.

The result is a simple and robust device with excellent performance in a variety of different operating conditions.

The range also includes a compact, two channel multi-mode FORJ and modules for more complex applications.

These modules can be coupled together to make multi-channel devices and combined with signal and high voltage slip rings.

In addition to fibre optic rotating joints the range includes the encoding and decoding devices that are used to covert the electrical signals for transfer down the fibre.

Interfaces are available for standard bus systems and video.

Fibre optic rotating joints are suitable for a wide variety of applications especially in difficult and hazardous areas including undersea telemetry, remotely operated vehicles, radar antennas, streamers and cable reels for military and commercial use.

The Model 197 is part of an extensive range of products available from IDM Electronics Ltd, part of the Kaydon Slipring Group that specialises in fibre and electrical transfer products.