Autonomous transport vehicle

• US 9,561,905 B2
• Filed: 12/15/2011
• Issued: 02/07/2017
• Est. Priority Date: 12/15/2010
• Status: Active Grant

• Current Assignee: Symbotic, Llc
• Original Assignee: Symbotic, Llc
• Inventors: Toebes, Stephen C., Holwell, Justin
• Primary Examiner(s): Snelting, Jonathan
• Application Number:
  US13/326,423
• Publication Number:
  US 20120189409A1
• Time in Patent Office: 1,881 Days
• Field of Search: 414/273, 414/401, 414/402, 180/168, 701/25, 364/424
• US Class Current: 1/1
• CPC Class Codes: B65G 1/0492 with cars adapted to travel in storage aisles

Abstract

An autonomous transport vehicle including a frame having a longitudinal axis extending from a front of the frame to a back of the frame, at least one first guide member mounted on one side of the frame and having a first guide member frame of reference, and at least one second guide member mounted to an opposite side of the frame than the at least one first guide member and having a second guide member frame of reference, wherein the first and second guide members are asymmetrically compliant guide members so that a stiffness of the at least one first guide member in response to a force in a predetermined direction relative to the first guide member frame of reference is different than a stiffness of the at least second guide member in response to the force in the predetermined direction relative to the second guide member frame of reference.

Claims

1. An autonomous transport vehicle comprising:

a frame having a longitudinal axis extending from a front of the frame to a back of the frame;

at least one first guide member mounted on one side of the frame and having a first guide member frame of reference; and

at least one second guide member mounted to an opposite side of the frame than the at least one first guide member and having a second guide member frame of reference;

wherein the first and second guide members are asymmetrically compliant guide members so that a stiffness of the at least one first guide member in response to a force in a predetermined direction relative to the first guide member frame of reference is different than a stiffness of the at least second guide member in response to the force in the predetermined direction relative to the second guide member frame of reference and a stiffness of the at least one first guide member at a respective guide surface in response to a force in a different predetermined direction relative to the first guide member frame of reference is the same as a stiffness of the at least one second guide member at a respective guide surface in response to the force in the different predetermined direction relative to the second guide member frame of reference.

2. The autonomous transport vehicle of claim 1, wherein the at least one first guide member includes a first yoke pivotally mounted to the frame about a first pivot member and a first engagement member mounted to the first yoke, and the at least one second guide member includes a second yoke pivotally mounted to the frame about a second pivot member and a second engagement member mounted to the second yoke.

3. The autonomous transport vehicle of claim 2, wherein the first engagement member is longitudinally offset from the first pivot member.

4. The autonomous transport vehicle of claim 2, wherein the second engagement member is transversely aligned with the second pivot member.

5. The autonomous transport vehicle of claim 1, wherein one or more of the at least one first and at least one second guide members comprise rotatable wheels.

6. The autonomous transport vehicle of claim 1, wherein the at least one first guide member comprises two first guide members and the at least one second guide member comprises two second guide members, the two first guide members being located on a first side of the autonomous transport vehicle and the two second guide members being located on a second opposite side of the autonomous transport vehicle.

7. The autonomous transport vehicle of claim 1, wherein the autonomous transport vehicle is configured for transporting items between the autonomous transport vehicle and storage shelves of a storage and retrieval system and the at least one second guide member is configured to maintain a predetermined transverse distance between the autonomous transport vehicle and the items stored on the storage shelves.

8. The autonomous transport vehicle of claim 1, wherein further the at least one first and at least second guide members are configured to interface with a first guide rail and a second guide rail of a storage and retrieval system where the first and second guide rails are located on opposite sides of the autonomous transport vehicle for guiding the autonomous transport vehicle along a substantially straight path.

9. The autonomous transport vehicle of claim 8, wherein one of the at least one first and at least one second guide members is configured to engage one of the first and second guide rails such that another one of the at least one first and at least one second guide member is held against another one of the first and second guide rails.

10. The autonomous transport vehicle of claim 8, wherein the at least one first and at least second guide members are configured to interface with a first and second contoured guide members extending from respective ones of the first and second guide rails where the first and second contoured guide members have opposing contours for directing a respective one of the at least first and the at least second guide members into engagement with a respective one of the first and second guide rails.

11. The autonomous transport vehicle of claim 1, wherein the autonomous transport vehicle is configured to travel along at least picking aisles of a storage and retrieval system and the at least one first guide member and the at least one second guide member are configured such that the autonomous transport vehicle can enter the picking aisles with the front of the autonomous transport vehicle leading or trailing a direction of travel of the autonomous transport vehicle.

12. The autonomous transport vehicle of claim 1, wherein the storage and retrieval system further includes a conveyor interface section, the at least one first guide member and the at least one second guide member are configured such that the autonomous transport vehicle can enter the conveyor interface section with the front of the autonomous transport vehicle leading or trailing a direction of travel of the autonomous transport vehicle.

13. An automated transport vehicle for transporting items in a storage and retrieval system where the storage and retrieval system includes picking aisles adjacent item storage locations, the automated transport vehicle comprises:

a frame having a front end, a back end and a longitudinal axis extending between the front and back ends;

a pair of first guide members are located on a first side of the frame where one of the first guide members is located adjacent the front end and the other of the first guide members is located adjacent the back end, each guide member of the pair of first guide members having a first guide member frame of reference; and

a pair of second guide members are located on a second side of the frame, opposite the first side, where one of the second guide members is located adjacent the front end and the other of the second guide members is located adjacent the back end, each guide member of the pair of second guide members having a second guide member frame of reference;

wherein the pair of first guide members and the pair of second guide members are asymmetrically compliant so that a stiffness of each one of the pair of first guide members in response to a force in a predetermined direction relative to a respective first guide member frame of reference is different than a stiffness of each one of the pair of second guide members in response to the force in the predetermined direction relative to a respective second guide member frame of reference and a stiffness of the at least one first guide member at a respective guide surface in response to a force in a different predetermined direction relative to the first guide member frame of reference is the same as a stiffness of the at least one second guide member at a respective guide surface in response to the force in the different predetermined direction relative to the second guide member frame of reference.

14. The automated transport vehicle of claim 13, wherein each guide member of the pair of first guide members are configured to pivot relative to the frame when a resultant force applied to the guide wheel is at an angle relative to the longitudinal axis.

15. The automated transport vehicle of claim 13, wherein the pair of first guide members is configured to maintain the autonomous transport vehicle at a predetermined distance within the picking aisles from items in the storage locations.

16. The automated transport vehicle of claim 13, wherein the pair of first guide members and the pair of second guide members are configured to allow the autonomous transport vehicle to traverse the picking aisle with either the front end or back end leading a direction of travel through the picking aisle.

17. The automated transport vehicle of claim 13, wherein the storage and retrieval system further includes conveyor interface sections and the pair of first guide members and the pair of second guide members are configured to allow the autonomous transport vehicle to traverse the conveyor interface section with either the front end or back end leading a direction of travel through the conveyor interface section.

18. A storage and retrieval system comprising:

a transfer deck;

picking aisles in communication with the transfer deck; and

at least one autonomous transport vehicle configured to traverse the transfer deck and picking aisles, the at least one autonomous transport vehicle having

a frame with a front end and a back end and a longitudinal axis extending between the front and back ends, and

at least one first guide member disposed on a first side of the frame and at least one second guide member disposed on a second opposite side of the frame where the at least one first guide member and the at least one second guide member are asymmetrically compliant so that a stiffness of the at least one first guide member in response to a force in a predetermined direction relative to the first guide member frame of reference is different than a stiffness of the at least second guide member in response to the force in the predetermined direction relative to the second guide member frame of reference and a stiffness of the at least one first guide member at a respective guide surface in response to a force in a different predetermined direction relative to the first guide member frame of reference is the same as a stiffness of the at least one second guide member at a respective guide surface in response to the force in the different predetermined direction relative to the second guide member frame of reference.

19. The storage and retrieval system of claim 18, wherein the at least one first guide member includes at least one first guide wheel and a first pivot member rotatably mounted to the frame and the at least one second guide member includes at least one second guide wheel and a second pivot member rotatably mounted to the frame, the at least one first guide wheel being rotatably mounted to the first pivot member where an axis of rotation of the first pivot member is located transversely in-line with a rotation axis of the at least one first guide wheel, and the at least one second guide wheel is rotatably mounted to the second pivot member where an axis of rotation of the second pivot member is longitudinally spaced from an axis of rotation of the at least one second guide wheel.

20. The storage and retrieval system of claim 18, wherein the storage and retrieval system further includes conveyor interface sections having two transfer deck interfaces with the transfer deck configured for autonomous transport vehicle entry/exit to/from the conveyor interface sections and the autonomous transport vehicle is configured to one or more of enter/exit the two transfer deck interfaces with either of the front and back ends leading a direction of travel through the conveyor interface section and enter/exit and traverse the picking aisles with either of the front and back ends leading a direction of travel through the storage location picking aisles.