Articulated vehicle

An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing the vehicle to turn more sharply. There are many kinds of articulated vehicles, from heavy equipment to buses, trams and trains. Steam locomotives were sometimes articulated in that the driving wheels could pivot around

In a broader sense, any vehicle towing a trailer could be described as articulated (the word articulated comes from the Latin articulus : small joint). In the UK, the term "articulated lorry" refers to the combination of a tractor and a trailer, abbreviated to "artic". In the U.S., this is called a semi-trailer truck, "tractor-trailer" or "semi-truck" and would not necessarily be called articulated.

The "integral unit," or "Integrated Tug and Barge" (ITB), comprises specially designed vessels that lock together in such a rigid and strong method as to be certified as such by authorities (classification societies) such as the American Bureau of Shipping, Lloyd's Register of Shipping, Indian Register of Shipping, Det Norske Veritas or several others. These units stay combined under virtually any sea conditions and the "tugs" usually have poor sea-keeping designs for navigation without their "barges" attached. Vessels in this category are legally considered to be ships rather than tugboats and barges must be staffed accordingly. These vessels must show navigation lights compliant with those required of ships rather than those required of tugboats and vessels under tow. "Articulated Tug and Barge" (ATB) units also utilize mechanical means to connect to their barges. ATBs generally utilize Intercon and Bludworth connecting systems. ATBs are generally staffed as a large tugboat, with between seven and nine crew members. The typical American ATB operating on the east coast, per custom, displays navigational lights of a towing vessel pushing ahead, as described in the '72 COLREGS.

Buses are articulated to allow for a much longer bus which can still navigate within the turning radius of a normal bus.

In the UK, tractor unit and trailer combinations are referred to as "articulated lorries".

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