TRAM ON TYRES
Tram on tyres are one of the most innovative guided transport systems.
They are also called "intermediate systems""; infact this technology mixes trolleybus and tramway features; in France, they are often named TRG, acronyme of "transport routier guidé".
Tra i sistemi di trasporto più innovativi vi sono i veicoli su gomma a via guidata.

The concept of tram on tyres is very recent (some lines are going to be opened in these months) and derives from the research of a flexible and reversible vehicle, which works mostly in guided mode (in order to maximize the system capacity, the performances and the reduction of the reserved lanes width) but able to switch in trolleybus-like mode, or, in some cases, running in the road traffic with autonomous power supply (batteries, diesel engine, etc.), like a normal bus.
This feature could be very important in the ancient city centers of many towns, characterized by road narrowness and many difficulties to insert heavy infrastructures (like the ordinary rails) in a historic texture.

These new trams use rubber tyres, in order to maximize the on board comfort and the cinematic performances (low horizontal curve radius, high vertical gradients - in many cases more than 10%).

Every tram on tyre model is characterized by a specific kind of guidance system: at the moment there are 4 main systems:
CIVIS (produced by Irisbus-Siemens), with optical guidance
GLT (produced by Bombardier), with mechanical guidance (central rail)
PHILEAS (produced by APTS), with magnetical guidance
TRANSLOHR (produced by Lohr), with mechanical guidance (central rail)


Links to the producers sites:
APTS
BOMBARDIER
IRISBUS
LOHR