Feb/March 2007

A trailer tracking system called CMS Trailer Tracker that works both in the depot and round the country has been launched by CMS Global Technologies.

In neither case is there is a need for the trailer itself to be equipped with a GPS tracking device or GSM transmitter; it simply incorporates a low-cost, low-power wireless device that reports on its identity.

The key to the system is a technology called ZigBee, which is a low-power, short-range wireless standard. The on-board trailer equipment uses this to communicate with the outside world.

When the trailer is coupled to a tractor unit, its ZigBee device communicates with a full GPS/GSM tracking system in the tractor cab. Providing the truck's 'black box' has appropriate capability, it can record when a particular trailer is picked up, when it is dropped off and where it has been in transit.

When the trailer is standing on its own in a depot, it communicates with a fixed system on the site (no GPS is required in this case, since the base station is at a known location). The black box can quickly determine which trailers are on site at any given time, and provide a record of when they arrived and left.

The system is operated by CMS on a hosted basis. The database on the Web server is available for viewing online for at least one year, and archives of older data are said to be retained indefinitely.

The ideal application, says CMS, would integrate the system with its own SupaTrak and/or Mobile Worker systems. Users then get the benefit of a fully-featured UK and European mapping interface, which adds more refinement in terms of in-the-field task management.

ZigBee uses 'mesh' technology, which means information from many sensors can be pooled for communication over large distances. It operates in the 2.4GHz frequency band (like Wi-Fi), and the standard has been ratified as IEEE 802.15.4. Transmission speed is 200Kbps at 90ft, and range can be up to 250ft. CMS says the batteries should last for at least a year.