Automatic transport loading system and method

• US 20050244259A1
• Filed: 05/02/2005
• Published: 11/03/2005
• Est. Priority Date: 05/03/2004
• Status: Active Grant

• Current Assignee: Jervis B Webb Company (Daifuku Company Limited)
• Original Assignee: Jervis B Webb Company (Daifuku Company Limited)
• Inventors: Simon, Christopher James, Chilson, Gerald Edward, Marino, Mark, Stevenson, Mark Andrew
• Granted Patent: US 7,648,329 B2
• Time in Patent Office: Days
• US Class Current: 414/664
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60L 15/38 with automatic control
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2200/42 Fork lift trucks
• CPC Class Codes: B60L 2260/32 Auto pilot mode
• CPC Class Codes: B66F 9/063 Automatically guided
• CPC Class Codes: B66F 9/0755 Position control; Position detectors
• CPC Class Codes: B66F 9/085 Multiple forks, i.e. more than one pair mounted on a single mast or with more than one mast
• CPC Class Codes: G05D 1/0238 using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• CPC Class Codes: G05D 1/024 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G05D 2201/0216 Vehicle for transporting goods in a warehouse, factory or similar
• CPC Class Codes: Y02P 90/60 Electric or hybrid propulsion means for production processes
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A method and system for automatically loading and unloading a transport is disclosed. A first guidance system is used to travel near the transport and a second guidance system is used to travel on the transport.

Claims

1. A method for loading a transport with an automatic guided vehicle (AGV) comprising:

engaging a load with said AGV;

guiding said AGV with a first guidance system to a first position;

guiding said AGV with a second guidance system from said first position to an intended load position on said transport;

depositing said load onto said transport at said intended load position; and

guiding said AGV with said second guidance system from said intended load position to a second position.

2. The method of claim 1 wherein said second guidance system comprises at least one distance measuring sensor.

3. The method of claim 2 wherein said at least one distance measuring sensor determines a first distance to a side of said transport.

4. The method of claim 1 wherein said first guidance system comprises an inertial guidance system.

5. The method of claim 1 wherein said first position is approximately at an end of the transport.

6. The method of claim 1 wherein said second position is similar to said first position.

7. The method of claim 1 wherein the step of guiding said AGV with said second guidance system from said first position to said intended load position on said transport comprises monitoring a drive current of said AGV.

8. The method of claim 7 wherein the step of guiding said AGV with said second guidance system from said first position to said intended load position on said transport further comprises shifting said load to a side of said transport.

9. The method of claim 8 wherein the step of shifting said load to a side of said transport comprises determining when said load has reached said side of said transport.

10. A method for loading a transport with an automatic guided vehicle (AGV) comprising:

engaging a load with said AGV;

guiding said AGV with a first guidance system to a first position, wherein said first guidance system comprises an inertial guidance system and said first position is proximate to said transport;

guiding said AGV with a second guidance system from said first position to an intended load position on said transport, wherein said second guidance system comprises at least one distance measuring device, said at least one distance measuring device determines a first distance to a side of said transport, whereby said first distance assists with the step of guiding said AGV with said second guidance system from said first position to said intended load position;

depositing said load onto said transport at said intended load position;

guiding said AGV with said second guidance system from said intended load position to a second position; and

guiding said AGV with said first guidance system from said second position.

11. The method of claim 10 wherein said first guidance system further comprises a track wheel.

12. The method of claim 10 wherein said first guidance system tracks said AGV throughout the steps of guiding said AGV with said second guidance system from said first position to said intended load position, depositing said load onto said transport at said intended load position and guiding said AGV with said second guidance system from said intended load position to said second position.

13. An automatic transport loading system comprising:

an automatic guided vehicle (AGV), said AGV comprising a drive mechanism and a steering mechanism; and

a first guidance system and a second guidance system, said first and second guidance systems being operatively coupled with said drive and said steering mechanisms of said AGV,

wherein said first guidance system guides said AGV to a first location, said second guidance system guides said AGV from said first position to an intended load position and from said intended load position to a second position, and said first guidance system guides said AGV from said second position.

14. The system of claim 13 further comprising a load position sensing device operatively coupled with said drive mechanism and said steering mechanism, said load position sensing device being capable of determining when said AGV is in said intended load position.

15. The system of claim 14 wherein said load position sensing device comprises at least one sensor, said sensor being capable of tracking movement of a load engaged with said AGV.

16. The system of claim 13 wherein said second position is approximately at said first position.

17. The system of claim 13 wherein said second guidance system comprises at least one distance measuring device, said at least one distance measuring device determines a first distance to a side of said transport, whereby said first distance assists with guiding said AGV with said second guidance system from said first position to said intended load position.

18. The system of claim 17 wherein said first guidance system comprises an inertial guidance system.

19. The system of claim 13 wherein said second guidance system comprises a sensor, said sensor being capable of detecting a side of said transport.

20. The system of claim 19 wherein said sensor comprises an encoder, said encoder being capable of tracking movement of a load engaged with said AGV.

21. The system of claim 20 wherein said encoder detects said intended load position by determining when said load is impeded from movement.

22. A method for loading a transport with an automatic guided vehicle (AGV) comprising:

engaging a load with said AGV;

guiding said AGV with a guidance system from a first position to an intended load position on said transport, whereby said guidance system locates said intended load position based on a location of said transport in relation to said first position;

depositing said load onto said transport at said intended load position; and

guiding said AGV with said guidance system from said intended load position to a second position.

23. The method of claim 22 wherein the step of locating said intended load position comprises determining a skew of said transport in relation to an expected transport position.

24. The method of claim 23 wherein the step of determining said skew of said transport comprises measuring a first distance to a first side of said transport, measuring a second distance to a second side of said transport, and comparing said first and second distances.

25. The method of claim 24 wherein said guidance system utilizes said skew to assist with guiding the AGV.

26. A method for unloading a transport with an automatic guided vehicle (AGV) comprising:

guiding said AGV with a guidance system from a first position to an approximate load position on said transport, whereby said guidance system locates said approximate load position based on a location of said transport in relation to said first position;

determining a load position;

engaging a load with said AGV at said load position; and

guiding said AGV with said guidance system from said approximate load position to a second position.

27. The method of claim 26 wherein the step of locating said approximate load position comprises determining a skew of said transport in relation to an expected transport position.

28. The method of claim 27 wherein the step of determining said skew of said transport comprises measuring a first distance to a first side of said transport, measuring a second distance to a second side of said transport, and comparing said first and second distances.

29. The method of claim 28 wherein said guidance system utilizes said skew to assist with guiding the AGV.

30. A method for unloading a transport with an automatic guided vehicle (AGV) comprising:

guiding said AGV with a first guidance system to a first position;

guiding said AGV with a second guidance system from said first position to an expected load position on said transport;

determining a load position;

engaging a load with said AGV at said load position; and

guiding said AGV with said second guidance system from said intended load position to a second position.

31. The method of claim 30 wherein said second guidance system comprises at least one distance measuring sensor.

32. The method of claim 31 wherein said at least one distance measuring sensor determines a first distance to a side of said transport.

33. The method of claim 30 wherein said first guidance system comprises an inertial guidance system.

34. The method of claim 30 wherein said first position is approximately at an end of the transport.

35. The method of claim 30 wherein said second position is similar to said first position.

36. The method of claim 30 wherein the step of determining a load position comprises monitoring a drive current of said AGV.

37. The method of claim 30 wherein the step of determining a load position comprises utilizing at least one optical sensor to detect a load pocket.