AUTOMATED BOT TRANSFER ARM DRIVE SYSTEM

• US 20120185082A1
• Filed: 12/15/2011
• Published: 07/19/2012
• Est. Priority Date: 12/15/2010
• Status: Active Grant

• Current Assignee: Symbotic, Llc
• Original Assignee: Casepick Systems, LLC
• Inventors: Toebes, Stephen C., Sullivan, Robert
• Granted Patent: US 9,499,338 B2
• Time in Patent Office: Days
• US Class Current: 700/218
• CPC Class Codes: B65G 1/0492 with cars adapted to travel in storage aisles

Abstract

An autonomous transport vehicle including a transfer arm including at least one finger and a movable finger support member, at least one sensor configured to detect movement of the at least one finger, the at least one sensor having a registration member and a detection member where one of the registration member and detection member is mounted to each of the at least one finger so as to be movable with a respective one of the at least one finger and the other one of the registration member and detection member is stationary relative to the at least one finger, and a controller in communication with the at least one sensor, the controller being configured to determine a position of the at least one finger along the second direction based on a proximity of the registration member relative to the detection member.

Claims

1. An autonomous transport vehicle comprising:

a transfer arm including at least one finger and a movable finger support member, the at least one finger being movably coupled to the finger support member so that the finger support member moves in a first direction and the at least one finger moves relative to the finger support member in a second direction substantially perpendicular to the first direction;

at least one sensor configured to detect movement of the at least one finger, the at least one sensor having a registration member and a detection member where one of the registration member and detection member is mounted to each of the at least one finger so as to be movable with a respective one of the at least one finger and the other one of the registration member and detection member is stationary relative to the at least one finger; and

a controller in communication with the at least one sensor, the controller being configured to determine a position of the at least one finger along the second direction based on a proximity of the registration member relative to the detection member.

2. The autonomous transport vehicle of claim 1, wherein the other one of the registration member and detection member is mounted on the movable finger support.

3. The autonomous transport vehicle of claim 1, wherein the at least one sensor is an optical, capacitive or inductive sensor.

4. The autonomous transport vehicle of claim 1, wherein the registration member comprises a reflective flag or a magnetic source.

5. The autonomous transport vehicle of claim 1, wherein the autonomous transport vehicle includes a drive unit for each of the at least one finger, where the controller is configured to actuate the drive unit for each of the at least one finger so each of the at least one finger are moved along the second direction substantially in unison.

6. The autonomous transport vehicle of claim 1, wherein the drive unit for each of the at least one finger includes a stepper motor.

7. The autonomous transport vehicle of claim 1, wherein the controller is configured to selectively move each of the at least one finger along the second direction depending on a size of a pickface carried by the autonomous transport vehicle.

8. The autonomous transport vehicle of claim 1, wherein the autonomous transport vehicle includes an inertial sensor coupled to the controller, the inertial sensor being configured to detect a tilt of the autonomous transport vehicle relative to a horizontal plane.

9. A storage and retrieval system comprising:

at least one multilevel vertical conveyor; and

at least one autonomous transport vehicle, the at least one autonomous transport vehicle including a controller and an inertial sensor configured to detect a tilt of the autonomous transport vehicle when the autonomous transport vehicle contacts a moving shelf of the at least one multilevel vertical conveyor, when the tilt exceeds a predetermined amount of tilt the controller is configured to at least in part effect stopping movement of the multilevel vertical conveyor.

10. The autonomous transport vehicle of claim 9, wherein the storage and retrieval system further comprising a control server in communication with the controller of the autonomous transport vehicle, the control server being configured to receive a signal from the controller regarding the tilt of the autonomous transport vehicle and to stop movement of the multilevel vertical conveyor.

11. The autonomous transport vehicle of claim 9, wherein the autonomous transport vehicle further includes a transport arm for interacting with a moving shelf of the multilevel vertical conveyor, the controller being configured to cause a retraction of the transport arm substantially upon detection of the tilt exceeding the predetermined amount of tilt.

12. An autonomous transport vehicle comprising:

a transfer arm having a finger support member and a plurality of fingers movable coupled to the finger support member;

wherein the autonomous transport vehicle further comprising a drive unit coupled to each of the plurality of fingers for independently moving a respective finger relative to the finger support member and a controller connected to each of the drive units for selectively actuating the drive units such that a single start or stop command from the controller causes activation or deactivation of the selected drive units in unison.

13. The autonomous transport vehicle of claim 12, wherein each of the drive units includes a stepper motor and a linear actuator where the stepper motor is coupled to a respective one of the plurality of fingers through the linear actuator.

14. The autonomous transport vehicle of claim 12, wherein the linear actuator comprises a ball screw.

15. The autonomous transport vehicle of claim 12, wherein one or more of the plurality of fingers includes a sensor connected to the controller, the sensor being configured to send a signal to the controller indicating the one or more of the plurality of fingers are located at a predetermined position relative to the finger support member.

16. The autonomous transport vehicle of claim 12, wherein the controller is configured to stop movement of the one or more of the plurality of fingers upon receipt of the signal indicating the one or more of the plurality of fingers are located at a predetermined position relative to the finger support member.