Traveling vehicle system and method of avoiding interference with traveling vehicle

• US 8,571,742 B2
• Filed: 02/01/2011
• Issued: 10/29/2013
• Est. Priority Date: 02/12/2010
• Status: Active Grant

• Current Assignee: Murata Machinery Limited (Muratec)
• Original Assignee: Murata Machinery Limited (Muratec)
• Inventors: Takeoka, Hidehiro
• Primary Examiner(s): CAMBY, RICHARD M
• Application Number:
  US13/018,536
• Publication Number:
  US 20110202247A1
• Time in Patent Office: 1,001 Days
• Field of Search: 701 23- 28, 701300-302, 701409-411, 340/435, 340/436
• US Class Current: 701/23
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S

Abstract

A traveling vehicle is equipped with an obstacle sensor to detect a distance to an obstacle and an orientation relative to the obstacle. A map of a travel route of the traveling vehicle is stored. A detection area where deceleration of the traveling vehicle is required if there is any obstacle in the detection area is repeatedly generated based on the position of the traveling vehicle from the map. Among obstacles detected by the obstacle sensor, an obstacle in the detection area is detected. Deceleration control of the traveling vehicle is implemented to prevent interference with the detected obstacle.

Claims

1. An overhead traveling vehicle system comprising:

overhead traveling vehicles each including an obstacle sensor configured to detect a distance to an obstacle and an orientation relative to the obstacle;

a map memory configured to store a map of a travel route of the overhead traveling vehicles;

a detection area generator configured to repeatedly define detection areas from the map based on current positions of the overhead traveling vehicles, the overhead traveling vehicles being decelerated if any obstacle is present in the detection areas;

an interference detector configured to detect an obstacle in the detection area, among obstacles detected by the obstacle sensor; and

a travel controller configured to control deceleration of the overhead traveling vehicles to prevent interference with the obstacle detected by the interference detector;

wherein

the detection area generator is configured to;

determine interference ranges ahead of the overhead traveling vehicles where obstacles in the interference ranges may cause interference with the overhead traveling vehicles, from the map and based on the positions of the overhead traveling vehicles,

determine positions of front ends of the overhead traveling vehicles when the overhead traveling vehicles stop, based on current velocities of the overhead traveling vehicles, and

in the interference ranges, designate areas closer to the overhead traveling vehicles in comparison with the positions of the front ends as the detection areas, and

the travel route includes diverging sections configured to allow the overhead traveling vehicles to move straight or to diverge from the diverging sections; and

the detection area generator is configured to define different detection areas in the vicinity of the diverging sections into diverging directions and straight directions, according to directions in which the overhead traveling vehicles travel through the diverging sections.

2. The traveling vehicle system according to claim 1, the obstacle sensor being configured to scan areas ahead of the overhead traveling vehicles in traveling directions at predetermined intervals;

and

the detection area generator being configured to define the detection areas synchronously with detection of the obstacle by the obstacle sensor.

3. A method of preventing interference between overhead traveling vehicles and obstacles, the method comprising the steps of:

detecting distances to the obstacles and orientations relative to the obstacles by obstacle sensors in the overhead traveling vehicles;

defining detection areas where deceleration of the overhead traveling vehicles is required if there is any of the obstacles in the detection areas, based on a map of a travel route of the overhead traveling vehicles and current positions of the overhead traveling vehicles;

detecting obstacles in the detection areas, from among the obstacles detected by the obstacle sensors; and

controlling deceleration of the overhead traveling vehicles to prevent interference between the overhead traveling vehicles and the obstacles in the detection areas;

wherein

the step of defining detection areas includes;

determining interference ranges ahead of the overhead traveling vehicles where any of the obstacles in the interference ranges may cause interference with the overhead traveling vehicles, from the map and based on the positions of the overhead traveling vehicles,

determining positions of front ends of the overhead traveling vehicles when the overhead traveling vehicles stop, based on current velocities of the overhead traveling vehicles, and

in the interference ranges, designating areas closer to the overhead traveling vehicles in comparison with the positions of the front ends as the detection areas;

the travel route includes diverging sections configured to allow the overhead traveling vehicles to move straight or to diverge from the diverging sections; and

the step of defining the detection areas further includes defining different detection areas in the vicinity of the diverging sections into diverging directions and straight directions, according to directions in which the overhead traveling vehicles travel through the diverging sections.