SYSTEM AND METHOD FOR GUIDING A ROBOT CLEANER ALONG A PATH

• US 20150134144A1
• Filed: 05/22/2013
• Published: 05/14/2015
• Est. Priority Date: 06/07/2012
• Status: Active Grant

• Current Assignee: Versuni Holding BV
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Bron, Andries, Salverda, Lolke Klaas
• Granted Patent: US 9,280,158 B2
• Time in Patent Office: Days
• US Class Current: 701/2
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70

Abstract

Disclosed is a method of guiding a mobile robot, comprising: providing a transmitter (110), and having said transmitter transmit a guide signal (300) into a spatially bounded guide signal reception field (302); providing a mobile robot (200) including two mutually adjacently disposed guide signal sensors (210a, 210b), each configured to generate a reference signal that reflects its reception of the guide signal; and moving the robot along a boundary portion (306) of the guide signal reception field while, based on said reference signals, maintaining a tracking state in which a first of said guide signal sensors (210a) is positioned substantially on a first side of said boundary portion, and a second of said guide signal sensors (210b) is positioned substantially on an opposite, second side of said boundary portion (306). Also disclosed is a system implementing the method.

Claims

1. A system comprising:

a base station including a transmitter that is configured to transmit a guide signal into a guide signal reception field spatially bounded by at least one boundary portion;

a mobile robot including;

a drive system configured to drive the robot across a floor;

two mutually adjacently disposed guide signal sensors, each of which is configured to generate a reference signal that reflects its reception of the guide signal; and

a controller that is operably connected to the drive system and the guide signal sensors, and configured to control the drive system to move the robot along the at least one boundary portion of the guide signal reception field while, based on said reference signals, maintaining a tracking state in which a first of said guide signal sensors is positioned substantially on a first side of said boundary portion, inside of the guide signal reception field, and a second of said guide signal sensors is positioned substantially on a second side of said boundary portion, outside of the guide signal reception field.

2. The system according to claim 1, wherein the boundary portion has a width of less than 10 mm, within which width an intensity of the guide signal drops at least 75%.

3. The system according to claim 1, wherein the transmitter includes an infrared light emitter configured to emit an infrared guide signal, and

wherein each of the guide signal sensors includes an infrared light receiver sensitive to the infrared guide signal from the infrared light emitter.

4. The system according to claim 1, wherein, in an operational condition of the robot on the floor, the guide signal sensors are disposed at a substantially same tracking height above the floor.

5. The system according to claim 1, wherein the boundary portion, as seen in a top view perpendicular to the floor, is substantially straight.

6. The system according to claim 1, wherein the transmitter is configured to project the guide signal onto the floor, such that the guide signal reception field is at least partly defined by a reflection of the guide signal off the floor, and

wherein the boundary portion, as seen in a top view perpendicular to the floor is curved.

7. The system according to claim 1, wherein the transmitter is configured to vary the position of the guide signal reception field relative to the transmitter with time, so as to vary the position of the boundary portion.

8. The system according to claim 1, wherein the transmitter is configured to vary the shape of the guide signal reception field with time, so as to vary the shape of the boundary portion.

9. The system according to claim 1, wherein the base station includes a housing with a generally flat front side having at least part of the transmitter mounted therein,

wherein the robot includes a housing with a generally flat front side having said guide signal sensors mounted thereon, and

wherein the transmitter is configured to effect a guide signal reception field whose at least one boundary portion extends substantially perpendicular to said front side of the housing of the base station, at least immediately adjacent said front side.

10. The system according to claim 1, wherein the mobile robot is a robotic vacuum cleaner.

11. A mobile robot for tracking a boundary portion of a spatially bounded guide signal reception field into which a guide signal is transmitted by a transmitter, said robot comprising:

a drive system configured to drive the robot across a floor;

two mutually adjacently disposed guide signal sensors, each of which is configured to generate a reference signal that reflects its reception of the guide signal; and

a controller that is operably connected to the drive system and the guide signal sensors, and configured to control the drive system to move the robot along a boundary portion of the guide signal reception field while, based on said reference signals, maintaining a tracking state in which a first of said guide signal sensors is positioned substantially on a first side of said boundary portion, inside of the guide signal reception field, and a second of said guide signal sensors is positioned substantially on a second side of said boundary portion, outside of the guide signal reception field.

12. The mobile robot according to claim 11,

wherein each of the guide signal sensors includes an infrared light receiver sensitive to an infrared guide signal.

13. The mobile robot according to claim 11, wherein, in an operational condition of the robot on the floor, the guide signal sensors are disposed at a substantially same tracking height above the floor.

14. The mobile robot according to claim 11, wherein the guide signal sensors are spaced apart less than 10 mm.

15. A method of guiding a mobile robot, comprising:

providing a transmitter, and having said transmitter transmit a guide signal into a spatially bounded guide signal reception field;

providing a mobile robot including two mutually adjacently disposed guide signal sensors, each configured to generate a reference signal that reflects its reception of the guide signal;

moving the robot, along a boundary portion of the guide signal reception field while, based on said reference signals, maintaining a tracking state in which a first of said guide signal sensors is positioned substantially on a first side of said boundary portion, inside of the guide signal reception field, and a second of said guide signal sensors is positioned substantially on a second side of said boundary portion, outside of the guide signal reception field.