Safety compliance for mobile drive units

Patent metadata

Field	Value
Publication number	US-10962956-B2
Application number	US-201815901206-A
Country	US
Kind code	B2
Filing date	Feb 21, 2018
Priority date	Aug 29, 2014
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

Techniques for controlling mobile drive units (e.g., robots) in proximity to humans in a physical area are described. A management device may send an activity message to the mobile drive units instructing the mobile drive units to perform a set of activities. If a human is detected in the physical area, the management device or another mobile drive unit may send an activity command instructing a mobile drive unit to stop, reduce the speed at which it is traveling, to change its path of travel, or to continue performing its set of activities. If the mobile drive units do not receive the activity command, the mobile drive units may stop performing the set of activities. After the management device determines that the human has left the physical area, the management device may resume sending the activity message.

First claim

What is claimed is:

1. A system comprising:
a plurality of mobile drive units within a physical area;
one or more processors; and
one or more non-transitory computer-readable storage media storing instructions executable by the one or more processors, wherein executing the instructions causes the one or more processors to:
determine a first location of a mobile drive unit of the plurality of mobile drive units within the physical area;
determine a second location corresponding to a user device;
determine that a distance between the first location of the mobile drive unit and the second location of the user device;
based at least in part on the distance between the first location of the mobile drive unit and the second location of the user device, cause the mobile drive unit to perform a first set of operations;
determine a first update to the first location of the mobile drive unit;
identify a boundary of a safe zone within the physical area, the safe zone forming an area to be avoided by the mobile drive unit
determine that the mobile drive unit is within a second threshold distance of the boundary of the safe zone based at least in part on the first update to the first location; and
based at least in part on determining that the mobile drive unit is within the second threshold distance of the boundary of the safe zone, cause the mobile drive unit to halt motion, reduce speed, or move away from the boundary of the safe zone.

2. The system of claim 1 , wherein executing the instructions that cause the mobile drive unit to perform the first set of operations further causes the mobile drive unit to halt motion or reduce a speed of the mobile drive unit.

3. The system of claim 1 , wherein executing the instructions further causes the one or more processors to:
determine a second update to the second location corresponding to the user device;
calculate a new distance between the mobile drive unit and the user device based at least in part on the first update to the first location and the second update to the second location, wherein the mobile drive unit is caused to perform the second set of operations further based at least in part on the new distance between the mobile drive unit and the user device.

4. The system of claim 1 , wherein executing the instructions that identify the boundary of the safe zone causes the one or more processors to receive data from a transmitter device associated with the safe zone, wherein receiving the data from the transmitter device indicates that the mobile drive unit is within the second threshold distance of the boundary of the safe zone.

5. The system of claim 1 , wherein executing the instructions further causes the one or more processors to:
identify one or more locations at a threshold distance of the user device; and
generate the boundary of the safe zone based at least in part on identifying the one or more locations.

6. The system of claim 1 , wherein the boundary of the safe zone is user-defined.

7. The system of claim 1 , wherein the boundary of the safe zone is associated with a scheduled time period and is only enforced during the scheduled time period.

8. The system of claim 1 , wherein the boundary of the safe zone moves according to movement of the user device.

9. A computer-implemented method, comprising:
determining a first location of a mobile drive unit of a plurality of mobile drive units within a physical area, the mobile drive unit being configured to perform a set of activities within the physical area;
determining a second location corresponding to a user device;
calculating a distance between the first location of the mobile drive unit and the second location of the user device;
based at least in part on determining that the distance is less than a first threshold distance, causing the mobile drive unit to perform a set of operations;
determining a third location of the mobile drive unit
identifying a boundary of a safe zone within the physical area, the safe zone forming an area to be avoided by the mobile drive unit
determine that the mobile drive unit is within a second threshold distance of the boundary of the safe zone based at least in part on the third location; and
based at least in part on determining that the mobile drive unit is within the second threshold distance of the boundary of the safe zone, cause the mobile drive unit to halt motion, reduce speed, or move away from the boundary of the safe zone.

10. The computer-implemented method of claim 9 , wherein at least one of: the first location, the second location, or the third location is determined based at least in part on a fiducial marker of the physical area.

11. The computer-implemented method of claim 9 , further comprising transmitting, to a second mobile drive unit, the second location corresponding to the user device, wherein transmitting the second location corresponding to the user device causes the second mobile drive unit to perform operations comprising at least one of: modifying a speed associated with the second mobile drive unit or performing operations to avoid the second location.

12. The computer-implemented method of claim 9 , further comprising:
estimating a path of travel of the user device over a time interval; and
causing the mobile drive unit to exceed, over the time interval, the predetermined threshold distance with respect to the user device based at least in part on the path of travel estimated for the user device.

13. A computer-readable storage medium comprising computer-readable instructions that, upon execution by one or more processors of a user device, cause the one or more processors to perform operations comprising:
determining a first location of a mobile drive unit of a plurality of mobile drive units within a physical area, the mobile drive unit being configured to perform a set of activities within the physical area;
determining a second location corresponding to a human within the physical area;
determining that a distance between the first location of the mobile drive unit and the second location of the human is less than a predetermined threshold;
based at least in part on determining that the distance, causing the mobile drive unit to perform a first set of operations;
monitoring for first updates to the first location of the mobile drive unit;
identifying a boundary of a safe zone within the physical area, the safe zone forming an area to be avoided by the mobile drive unit;
determine that the mobile drive unit is within a second threshold distance of the boundary of the safe zone based at least in part on the first updates to the first location; and
based at least in part on determining that the mobile drive unit is within the second threshold distance of the boundary of the safe zone, cause the mobile drive unit to halt motion, reduce speed, or move away from the boundary of the safe zone.

14. The computer-readable storage medium of claim 13 , wherein the computer-readable instructions are executed by one or more processors of a management module configured to manage the plurality of mobile drive units with the physical area.

15. The computer-readable storage medium of claim 13 , wherein determining the second location of the human is based at least in part on receiving imaging data from one or more imaging devices located within the physical area, the one or more imaging devices including at least one of a stationary camera fixed in the physical area or a mobile camera mounted on mobile drive unit.

16. The computer-readable storage medium of claim 13 , wherein determining the second loca

Assignees

• Amazon Tech Inc

Inventors

• Stubbs Andrew
• Verminski Matthew David
• Barbehenn Michael T
• Tinka Andrew Brenden
• Mansfield Peter K
• Wurman Peter R

Classifications

• G05B19/0428 Primary

  Safety, monitoring (G05B19/0423 takes precedence) · CPC title

• Y02P90/60

  Electric or hybrid propulsion means for production processes · CPC title

• G05B2219/40202

  Human robot coexistence · CPC title

• G05B2219/40173

  Stop robot if no command received within interval · CPC title

• G05B19/41895

  using automatic guided vehicles [AGV] (control of position or course of AGV's G05D1/00) · CPC title