Electrostatic discharge systems for autonomous mobile robots

• US 10,517,455 B2
• Filed: 10/26/2017
• Issued: 12/31/2019
• Est. Priority Date: 10/26/2017
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Fay, Victor, Gschrey, Travis James
• Primary Examiner(s): Carlson, Marc
• Application Number:
  US15/794,543
• Publication Number:
  US 20190125154A1
• Time in Patent Office: 796 Days
• CPC Class Codes: A47L 2201/00 Robotic cleaning machines, i.e. with automatic control of the travelling movement or the cleaning operation
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 5/22 with rotary fans
• CPC Class Codes: A47L 9/0411 driven by electric motor
• CPC Class Codes: A47L 9/0472 Discs
• CPC Class Codes: A47L 9/0477 Rolls
• CPC Class Codes: A47L 9/0488 Combinations or arrangements of several tools, e.g. edge cleaning tools
• CPC Class Codes: A47L 9/2826 the condition of the floor
• CPC Class Codes: A47L 9/2852 Elements for displacement of the vacuum cleaner or the accessories therefor, e.g. wheels, casters or nozzles
• CPC Class Codes: A47L 9/2889 Safety or protection devices or systems, e.g. for prevention of motor over-heating or for protection of the user
• CPC Class Codes: H05K 9/0067 Devices for protecting against damage from electrostatic discharge

Abstract

An autonomous mobile robot includes a housing infrastructure, a drive system including one or more wheels to support the housing infrastructure above a floor surface, a cleaning assembly, electrical circuitry positioned within the robot housing and an electrostatic discharge assembly including an electrostatic discharge member that includes fibers electrically connected to the electrical circuitry and extending, from the electrical circuitry, to an exterior of the housing infrastructure. The electrical circuitry includes a controller to initiate a cleaning operation in which the drive propels the robot across the floor surface while the cleaning assembly cleans the floor surface.

Claims

1. An autonomous mobile robot comprising:

a housing infrastructure;

a drive system comprising one or more wheels to support the housing infrastructure above a floor surface;

a cleaning assembly comprising one or more of a rotatable member and a cleaning pad;

electrical circuitry positioned within the robot housing, the electrical circuitry including a controller to initiate a cleaning operation in which the drive propels the robot across the floor surface while the cleaning assembly cleans the floor surface; and

an electrostatic discharge assembly comprising an electrostatic discharge member that includes a plurality of fibers electrically connected to the electrical circuitry and extending, from the electrical circuitry, to an exterior of the housing infrastructure, wherein the electrostatic discharge member is distinct from the cleaning assembly.

2. The robot of claim 1, wherein:

the electrostatic discharge assembly comprises an assembly housing coupling the electrostatic discharge assembly to the housing infrastructure,

the plurality of fibers comprise proximal ends disposed within the assembly housing and distal ends disposed outside of the assembly housing and outside of the housing infrastructure.

3. The robot of claim 1, wherein:

the cleaning assembly is configured to contact the floor surface during the cleaning operation, thereby causing the robot to accumulate electrostatic charge, and

the electrostatic discharge member is configured to dissipate the accumulated electrostatic charge into an environment of the robot.

4. The robot of claim 1, wherein the electrostatic discharge member extends downward toward the floor surface.

5. The robot of claim 1, wherein a distance between a distal tip portion of the electrostatic discharge member and the floor surface is between 0.2 cm and 1.1 cm.

6. The robot of claim 1, wherein:

a height of the robot relative to the floor surface is no more than 13 centimeters, and

the electrostatic discharge member is positioned at a rearward portion of the housing infrastructure and along a bottom portion of the housing infrastructure.

7. The robot of claim 6, wherein the electrostatic discharge member extends rearwardly from the housing infrastructure.

8. The robot of claim 1, wherein the electrostatic discharge member is within an outer perimeter of the robot and extends toward a rearmost edge of the robot along an axis that forms an angle between 45 and 90 degrees with the floor surface.

9. The robot of claim 1, wherein a minimum distance between a distal tip portion of the electrostatic discharge member and an exterior wall of the housing infrastructure is at least 1 millimeter.

10. The robot of claim 1, wherein:

an exterior wall of the housing infrastructure comprises a first portion recessed inwardly relative to a second portion surrounding the first portion,

the electrostatic discharge member extends out of the housing infrastructure through the first portion of the exterior wall, and

a minimum distance between the distal tip portion and the second portion of the housing infrastructure is at least 1 millimeter.

11. The robot of claim 1, wherein:

the plurality of fibers comprise a plurality of distal tips, and

minimum distances between the plurality of distal tips and the exterior surface of the body are non-uniform.

12. The robot of claim 11, wherein the minimum distances are no more than 1.25 mm.

13. The robot of claim 11, wherein a maximum distance between any two of the plurality of distal tips is no more than 1.25 mm.

14. The robot of claim 11, wherein a diameter of each of the plurality of fibers is between 1 and 10 micrometers.

15. The robot of claim 11, wherein, for each of the plurality of fibers, a length between a proximal end of a fiber and a distal end of the fiber is between 3 and 20 millimeters.

16. The robot of claim 1, wherein a distance between a distal tip portion of the electrostatic discharge member and a rearmost edge of the housing infrastructure is between 1% and 5% of a length of the robot.

17. The robot of claim 1, wherein:

a bottom surface of the housing is no more than 0.7 cm from the floor surface, and

the electrostatic discharge member is positioned above the floor surface such that the electrostatic discharge member does not contact the floor surface during the cleaning operation on the floor surface.

18. The robot of claim 1, further comprising an assembly housing to which the electrostatic discharge member is mounted, the assembly housing comprising a locator member engaged with a corresponding locator member on the housing infrastructure to inhibit relative movement of the portion of the electrical circuitry and the electrostatic discharge member.

19. The robot of claim 1, further comprising a resistor electrically connecting the electrostatic discharge member and the electrical circuitry.

20. The robot of claim 19, wherein an electrical resistance of the electrical resistor is between 1 Kilo-Ohm and 1 Mega-Ohm.

21. The robot of claim 1, wherein the electrostatic discharge member is connected to an electrical ground of the electrical circuitry.

22. The robot of claim 1, wherein the electrostatic discharge member is electrically connected to the electrical circuitry through an electrical wire.

23. The robot of claim 1, wherein the electrostatic discharge member comprises carbon fibers.

24. The robot of claim 23, wherein the electrostatic discharge member extends downward toward the floor surface.

25. The robot of claim 24, wherein a distance between a distal tip portion of the electrostatic discharge member and the floor surface is between 0.2 cm and 1.1 cm.