Abstract: A carriage conveying apparatus has a loaded carriage to be conveyed, and a driving vehicle for coupling, towing and conveying the carriage from below the carriage. Since the vertical load of the carriage is transmitted to the driving vehicle, controlled to a proper magnitude, the driving vehicle may be reduced in size and weight, and it is also possible to have stable travel if the carriage is empty. By designing all three wheels so as to be driven and steered, sideways and spin-turn motions are realized. By providing recognition marks and detecting means, it is possible to position the driving vehicle accurately if the setting position of the carriage deviates.

Abstract: An automatic guided vehicle having three wheels consisting a front wheel and a pair of rear wheels and being capable of travelling along a track formed on a floor by a white line or aluminum foil while detecting the track by means of an optical type track sensor. The front wheel of this vehicle can be turned relative to a main body of the vehicle in response to a steering operation and can be locked in the lateral direction. The position of the pair of rear wheels can be symmetrically changed from a paralleled state to an orthogonal state relative to the center line of the main body to be maintained in these states, thereby enabling the main body to turn or laterally travel with radii of gyration determined in accordance with turning angles of the rear wheels relative to the main body on the basis of the relative turning and driving operations of the front and rear wheels.