AUTOMATIC GUIDED VEHICLE AND METHOD FOR DRIVE CONTROL OF THE SAME

• US 20120059545A1
• Filed: 09/01/2011
• Published: 03/08/2012
• Est. Priority Date: 09/03/2010
• Status: Active Grant

• Current Assignee: Hitachi Industrial Products, Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Plant Technologies Limited (Hitachi, Ltd.)
• Inventors: FURUNO, Hideaki, Yoshida, Yutaka, Tomioka, Yoshiharu
• Granted Patent: US 9,176,502 B2
• Time in Patent Office: Days
• US Class Current: 701/26
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0244 using reflecting strips
• CPC Class Codes: G05D 1/0282 generated in a local control room
• CPC Class Codes: G05D 2201/0216 Vehicle for transporting goods in a warehouse, factory or similar

Abstract

An automatic guided vehicle and a method for drive control enable setting the vehicle alongside a conveyor with high accuracy in stopping at a task address. An automatic guided vehicle includes photoelectric sensors which detect the presence of an article by projecting light to a reflecting plate arranged on a conveyor and receiving signal light reflected from the reflecting plate and are arranged in one at each of the front and rear portions of the automatic guided vehicle, and a unit for detecting the distance between the vehicle and the conveyor. When both the photoelectric sensors arranged at the front and read portions of the side surface of the vehicle, a steering vehicle is steered toward the conveyor, and the automatic guided vehicle is driven toward the conveyor until the distance between the vehicle and the conveyor becomes within a predetermined distance.

Claims

1. An automatic guided vehicle that approaches an object by performing route data driving when the vehicle is distant from the object, the route data driving being based on preset route data, and starting sensor driving when the vehicle has come close to the object, the sensor driving being based on a sensor thereof, the vehicle comprising:

a control section that determines whether or not a position obtained by the route data driving is a start point that is a position to start the sensor driving, and switches the route data driving to the sensor driving when the control section has determined that the vehicle is at the start point, to make the automatic guided vehicle approach the object.

2. The automatic guided vehicle according to claim 1, further comprising:

a laser distance sensor for measuring distances to surroundings by scanning with laser light, wherein the control section performs the route data driving with the laser distance sensor,

wherein the sensor for the sensor driving comprises;

a photo-detection sensor that projects a signal light to a reflecting plate arranged on the object, receives a reflected light from the reflecting plate, and thereby detects a presence of the object; and

a distance measuring sensor capable of measuring a distance to the object,

and wherein the control section performs the sensor driving with the photo-detection sensor and the distance measuring sensor.

3. The automatic guided vehicle according to claim 2,

wherein the distance measuring sensors are arranged at each of a front portion and a rear portion of a side surface of the automatic guided vehicle,

and wherein when the distance to the object measured by one of the distance measuring sensors is within a predetermined distance and the distance to the object measured by the other one of the distance measuring sensors is out of the predetermined distance, the control section controls the automatic guided vehicle such that the distance measuring sensor whose distance to the object is out of the predetermined distance approaches the object.

4. The automatic guided vehicle according to claim 1, further comprising:

a laser distance sensor for measuring distances to surroundings by scanning with laser light,

wherein the control section performs the route data driving with the laser distance sensor, and performs the sensor driving with the laser distance sensor as the sensor for the sensor driving.

5. The automatic guided vehicle according to claim 1, wherein the control section creates the start point at a position that is closer to the object than a route being set by the route data.

6. The automatic guided vehicle according to claim 2, wherein the control section creates the start point at a position that is closer to the object than a route being set by the route data.

7. The automatic guided vehicle according to claim 3, wherein the control section creates the start point at a position that is closer to the object than a route being set by the route data.

8. The automatic guided vehicle according to claim 4, wherein the control section creates the start point at a position that is closer to the object than a route being set by the route data.

9. The automatic guided vehicle according to claim 5, wherein the start point is managed with coordinates at predetermined two points of the automatic guided vehicle.

10. The automatic guided vehicle according to claim 6, wherein the start point is managed with coordinates at predetermined two points of the automatic guided vehicle.

11. The automatic guided vehicle according to claim 7, wherein the start point is managed with coordinates at predetermined two points of the automatic guided vehicle.

12. The automatic guided vehicle according to claim 8, wherein the start point is managed with coordinates at predetermined two points of the automatic guided vehicle.

13. A method for drive control of an automatic guided vehicle, comprising the steps of:

when the vehicle is distant from an object, performing route data driving that is based on preset route data; and

when the vehicle has come close to the object, starting sensor driving that is based on a sensor thereof, to make the vehicle approach the object,

wherein the automatic guided vehicle;

determines whether or not a position obtained by the route data driving is a start point that is a position to start the sensor driving; and

when the automatic guided vehicle is at the start point, switches the route data driving to the sensor driving, to make the automatic guided vehicle approach the object.

14. The method for drive control according to claim 13,

wherein the automatic guided vehicle comprises:

a laser distance sensor for measuring distances to surroundings by scanning with laser light,

wherein the sensor for the sensor driving comprises;

a photo-detection sensor that projects a signal light to a reflecting plate arranged on the object, receives a reflected light from the reflecting plate, and thereby detects a presence of the object; and

a distance measuring sensor capable of measuring a distance to the object,

and wherein the automatic guided vehicle;

performs the route data driving with the laser distance sensor up to the start point; and

performs the sensor driving with the photo-detection sensor and the distance measuring sensor from the start point.

15. The method for drive control according to claim 13,

wherein the automatic guided vehicle comprises:

a laser distance sensor for measuring distances to surroundings by scanning with laser light,

and wherein the automatic guided vehicle;

performs the route data driving with the laser distance sensor up to the start point; and

performs the sensor driving with the laser distance sensor as the sensor for the sensor driving after the start point.

16. The method for drive control according to claim 13,

wherein the automatic guided vehicle creates the start point at a position that is closer to the object than a route being set by the route data.

17. The method for drive control according to any one of claim 14,

wherein the automatic guided vehicle creates the start point at a position that is closer to the object than a route being set by the route data.

18. The method for drive control according to claim 15,

wherein the automatic guided vehicle creates the start point at a position that is closer to the object than a route being set by the route data.