To reduce the number of processes needed by setting a bypass route in such a constitution that a carriage is run by bypassing when bypass of a travel route is necessary.

In correspondence to a travel route P1 of a carriage 2A defined by vehicle alignment of nodes of consecutive numbers from (1) to (8), a bypass possible area A1 positioned at a place which is parallel to the travel route P1 and is apart from the travel route P1 for a prescribed distance C or longer is set. The prescribed distance C is the distance equal to a minimum distance of interference E or longer where two carriages can avoid contact. There are nodes (5) and (6) within the travel route P1 where entrance of the carriage 2A is blocked and, when bypass running of the carriage 2A is necessary, a bypass route R1 for passing the bypass possible area A1 corresponding to the travel route P1 is automatically created. Entrance of other carriages into nodes of consecutive numbers from (13) to (18) present within the prescribed distance C from the bypass route R1 is blocked.