Method and apparatus for sensing object load engagement, transportation and disengagement by automated vehicles

• US 8,538,577 B2
• Filed: 03/05/2010
• Issued: 09/17/2013
• Est. Priority Date: 03/05/2010
• Status: Active Grant

• Current Assignee: Crown Equipment Corporation
• Original Assignee: Crown Equipment Corporation
• Inventors: Bell, Jamie, Chandrasekar, Kashyap, Graham, Andres Evan, Howse, David Charles
• Primary Examiner(s): Jones, Yolanda
• Application Number:
  US12/718,620
• Publication Number:
  US 20110218670A1
• Time in Patent Office: 1,292 Days
• Field of Search: None
• US Class Current: 700/215
• CPC Class Codes: B66F 9/0755 Position control; Position detectors
• CPC Class Codes: B66F 9/20 Means for actuating or controlling masts, platforms, or forks power take-off from vehicle transmissions, combined with vehicle propulsion systems B60K
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means

Abstract

A method and apparatus for sensing object load engagement, transportation and disengagement by automated vehicles is described. In one embodiment, the method includes processing data that is transmitted from a sensor array comprising at least one device for analyzing a plurality of objects that are placed throughout a physical environment, executing an object recognition process on the sensor array data using model information to identify at least one object, determining orientation information associated with the at least one object, wherein the orientation information is relative to the lift carriage and positioning at least one lifting element based on the orientation information.

Claims

1. A method of operating a vehicle comprising a lift carriage to engage or disengage an object load in a physical environment comprising a warehouse rack system, the method comprising:

analyzing a plurality of objects that are placed throughout the physical environment by processing data that is transmitted from a sensor array attached to the lift carriage of the vehicle;

executing an object recognition process on the sensor array data to identify the rack system by comparing rack system models with the sensor array data;

utilizing the rack system identification and a software module resident on a mobile computer coupled to the vehicle or a central computer coupled to the sensor array via a network to align a lifting element of the vehicle with entry points for a pallet or a shelf within the rack system; and

operating the vehicle to engage or disengage the object load with the aligned lifting element.

2. The method of claim 1 wherein:

the vehicle comprises lifting forks and the sensor array is positioned below the lifting forks;

the method comprises utilizing a software module to determine if the target destination is clear of obstructions and disengaging the object load if the target destination is clear of obstructions; and

the software module is resident on (i) a mobile computer coupled to the vehicle or (ii) a central computer coupled to the sensor array via a network.

3. The method of claim 1 wherein the method comprises:

engaging an object load; and

utilizing a software module resident on a mobile computer coupled to the vehicle or a central computer coupled to the sensor array via a network to compute a distance to a center of the engaged object load; and

using the computed a distance to a center of the engaged object load and a stored displacement measurement between the vehicle and the engaged object load to calibrate the sensor array.

4. The method of claim 1 wherein the method further comprises:

scanning the object load while moving the lift carriage and the sensor array vertically;

executing an object recognition process on the sensor array data to identify a matching pallet model;

engaging or disengaging the object load based on the identification of the matching pallet model.

5. The method of claim 1 wherein the method further comprises utilizing a software module to define an entry point orientation associated with a shelf within the rack system, wherein the software module is resident on (i) a mobile computer coupled to the vehicle or (ii) a central computer coupled to the sensor array via a network.

6. The method of claim 1 wherein:

the sensor array comprises a camera attached to the lift carriage of the vehicle; and

the sensor array data comprises data captured by the laser scanner and the camera.

7. The method of claim 1 wherein:

the sensor array comprises a laser scanner and a camera attached to the lift carriage of the vehicle; and

the sensor array data comprises data captured by the laser scanner and the camera.

8. The method of claim 7 wherein the laser scanner and the camera operate with a light to enhance obstruction identification.

9. The method of claim 1 wherein the sensor array comprises a laser scanner and a camera attached to the lift carriage of the vehicle as a moveable sensor head attached to a pair of guide rails.

10. The method of claim 9 wherein a ball screw is utilized to raise or lower the sensor head or a driven linear slide table is employed to transport the sensor head.

11. The method of claim 9 wherein:

the vehicle comprises lifting forks and a drive motor connected to a gear, the gear engaging a rack in a rack and pinion arrangement; and

the method comprises utilizing the rack and pinion arrangement to move the sensor head to a location above the lifting forks, below the lifting forks, or both.

12. The method of claim 11 wherein the method comprises rotating the sensor head with the drive motor when capturing the sensor array data in order to identify objects or object loads that are not directly aligned with the forks.

13. The method of claim 1 wherein:

the sensor array comprises a laser scanner and a camera attached to the lift carriage of the vehicle;

the laser scanner and the camera are co-linear and orthogonal in the horizontal plane and coplanar in the vertical plane to an automated vehicle axis; and

the method comprises using a software module resident on a mobile computer coupled to the vehicle or a central computer coupled to the sensor array via a network to automatically cross correlate information between the laser scanner and the camera.

14. The method of claim 1 wherein:

the sensor array comprises a laser scanner and a camera attached to the lift carriage of the vehicle;

the method comprises using a software module to use geometric transforms to cross correlate information between the laser scanner and the camera; and

the software module is resident on (i) a mobile computer coupled to the vehicle or (ii) a central computer coupled to the sensor array via a network.

15. A system for operating an automated vehicle to engage or disengage an object load in a physical environment comprising a warehouse rack, the system comprising a mobile computer coupled to the vehicle, a central computer, and a sensor array attached to a lift carriage of the vehicle, wherein:

the mobile computer, the central computer, and the sensor array are coupled to each other through a network; and

software modules within the central computer, the mobile computer, or both, process data that is transmitted from the sensor array to facilitate object load engagement or disengagement by

executing an object recognition process on the sensor array data to identify the rack system by comparing rack system models with the sensor array data,

utilizing the identified rack system identification and a software module resident on a mobile computer coupled to the vehicle or a central computer coupled to the sensor array via a network to align a lifting element of the vehicle with entry points for a pallet or a shelf within the rack system, and

engaging or disengaging the object load with the aligned lifting element.