Travelling vehicle system and method for controlling travelling vehicle

1. A travelling vehicle system comprising:

a controller; and

a plurality of travelling vehicles, each of which travels along a track partially including a blocking area including a branching section, transmits a request for permission to pass through the blocking area to the controller, and passes through the blocking area when receiving passage permission from the controller, and stopping in front of the blocking area when receiving no passage permission, the controller canceling the passage permission for the travelling vehicle, to which the controller transmits the passage permission, after passage of the travelling vehicle through the blocking area; wherein

the controller is configured or programmed to include:

a first storage that stores a last permitted travelling vehicle, to which the passage permission is transmitted lastly and the passage permission for which is not canceled, for each direction in the branching section included in the blocking area;

a second storage that stores a last canceled travelling vehicle, the passage permission for which is canceled lastly, for each direction in the branching section included in the blocking area;

a third storage that stores the travelling vehicle, to which the passage permission in a same direction in the blocking area is transmitted lastly, as a forward travelling vehicle of a travelling vehicle waiting for the permission to pass through the blocking area at the time of transmission of the passage permission to the passage-permission waiting travelling vehicle; and

a determiner that determines whether to give passage permission to the travelling vehicle waiting for the permission to pass through the blocking area based on whether the forward travelling vehicle of the passage-permission waiting travelling vehicle coincides with the last permitted travelling vehicle or the last canceled travelling vehicle for the blocking area; and

when the last permitted travelling vehicle for the blocking area including the branching section is not stored in the first storage, if the last canceled travelling vehicle for the blocking area coincides with the forward travelling vehicle of the travelling vehicle waiting for the permission to pass through the blocking area, the determiner gives permission to pass through the blocking area to the passage-permission waiting travelling vehicle.

2. The travelling vehicle system according to claim 1 , wherein, when the last permitted travelling vehicle for the blocking area is stored in the first storage, if the last permitted travelling vehicle coincides with the forward travelling vehicle of the travelling vehicle waiting for the permission to pass through the blocking area and if a travelling direction of the passage-permission waiting travelling vehicle in the branching section included in the blocking area coincides with a direction of the last permitted travelling vehicle, the determiner gives permission to pass through the blocking area to the passage-permission waiting travelling vehicle.

3. A travelling vehicle system comprising:

a controller; and

a plurality of travelling vehicles, each of which travels along a track partially including a blocking area including a merging section, transmits a request for permission to pass through the blocking area to the controller, and passes through the blocking area when receiving passage permission from the controller, and stopping in front of the blocking area when receiving no passage permission, the controller canceling the passage permission for the travelling vehicle, to which the controller transmits the passage permission, after passage of the travelling vehicle through the blocking area; wherein

the controller is configured or programmed to include:

a first storage that stores a last permitted travelling vehicle, to which the passage permission is transmitted lastly and the passage permission for which is not canceled, for each direction in the merging section included in the blocking area;

a second storage that stores a last canceled travelling vehicle, the passage permission for which is canceled lastly, for each direction in the merging section included in the blocking area;

a third storage that stores the travelling vehicle, to which the passage permission in a same direction in the blocking area is transmitted lastly, as a forward travelling vehicle of a travelling vehicle waiting for the permission to pass through the blocking area at the time of transmission of the passage permission to the passage-permission waiting travelling vehicle; and

a determiner that determines whether to give passage permission to the travelling vehicle waiting for the permission to pass through the blocking area based on whether the forward travelling vehicle of the passage-permission waiting travelling vehicle coincides with the last permitted travelling vehicle or the last canceled travelling vehicle for the blocking area; and

when the last permitted travelling vehicle for the blocking area including the merging section is not stored in the first storage, if the last canceled travelling vehicle coincides with the forward travelling vehicle of the passage-permission waiting travelling vehicle, the last canceled travelling vehicle having entered the merging section in the same direction as the passage-permission waiting travelling vehicle in the blocking area, the determiner gives permission to pass through the blocking area to the passage-permission waiting travelling vehicle.

4. A method for controlling a travelling vehicle in a travelling vehicle system including a controller, and a plurality of travelling vehicles, each of which travels along a track partially including a blocking area including a branching section, transmits a request for permission to pass through the blocking area to the controller, and passes through the blocking area when receiving passage permission from the controller, and stopping in front of the blocking area when receiving no passage permission, the controller canceling the passage permission for the travelling vehicle, to which the controller transmits the passage permission, after passage of the travelling vehicle through the blocking area, the method comprising:

storing a last permitted travelling vehicle, to which the passage permission is transmitted lastly and the passage permission for which is not canceled, for each direction in the branching section included in the blocking area;

storing a last canceled travelling vehicle, the passage permission for which is canceled lastly, for each direction in the branching section included in the blocking area;

storing the travelling vehicle, to which the passage permission in a same direction in the blocking area is transmitted lastly, as a forward travelling vehicle of a travelling vehicle waiting for the permission to pass through the blocking area at the time of transmission of the passage permission to the passage-permission waiting travelling vehicle;

determining whether to give passage permission to the travelling vehicle waiting for the permission to pass through the blocking area based on whether the forward travelling vehicle of the passage-permission waiting travelling vehicle coincides with the last permitted travelling vehicle or the last canceled travelling vehicle for the blocking area; and

when the last permitted travelling vehicle for the blocking area including the branching section is not stored, if the last canceled travelling vehicle for the blocking area coincides with the forward travelling vehicle of the travelling vehicle waiting for the permission to pass through the blocking area, giving permission to pass through the blocking area to the passage-permission waiting travelling vehicle.