DEBRIS SENSOR FOR CLEANING APPARATUS

• US 20050162119A1
• Filed: 01/28/2004
• Published: 07/28/2005
• Est. Priority Date: 01/28/2004
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Cohen, David A., Landry, Gregg W., Ozick, Daniel
• Granted Patent: US 6,956,348 B2
• Time in Patent Office: Days
• US Class Current: 318/580
• CPC Class Codes: A47L 11/4005 Arrangements of batteries or cells; Electric power supply arrangements
• CPC Class Codes: A47L 11/4008 Arrangements of switches, indicators or the like
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4061 Steering means; Means for avoiding obstacles; Details related to the place where the driver is accommodated
• CPC Class Codes: A47L 11/4066 Propulsion of the whole machine
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 2201/06 Control of the cleaning action for autonomous devices; Automatic detection of the surface condition before, during or after cleaning
• CPC Class Codes: A47L 5/362 of the horizontal type, e.g. canister or sledge type
• CPC Class Codes: A47L 9/0466 Rotating tools
• CPC Class Codes: A47L 9/0488 Combinations or arrangements of several tools, e.g. edge cleaning tools
• CPC Class Codes: A47L 9/2805 Parameters or conditions being sensed
• CPC Class Codes: A47L 9/281 the amount or condition of incoming dirt or dust
• CPC Class Codes: A47L 9/2831 Motor parameters, e.g. motor load or speed
• CPC Class Codes: A47L 9/2842 Suction motors or blowers
• 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 9/2857 User input or output elements for control, e.g. buttons, switches or displays
• CPC Class Codes: A47L 9/2884 Details of arrangements of batteries or their installation
• 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: A47L 9/2894 Details related to signal transmission in suction cleaners
• CPC Class Codes: G05D 1/021 specially adapted to land vehicles
• CPC Class Codes: G05D 1/0227 : using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0238 : using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• CPC Class Codes: G05D 1/0242 : using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0272 : comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: Y10S 901/01 : Mobile robot
• CPC Class Codes: Y10S 901/46 : Sensing device

Abstract

A piezoelectric debris sensor and associated signal processor responsive to debris strikes enable an autonomous or non-autonomous cleaning device to detect the presence of debris and in response, to select a behavioral mode, operational condition or pattern of movement, such as spot coverage or the like. Multiple sensor channels (e.g., left and right) can be used to enable the detection or generation of differential left/right debris signals and thereby enable an autonomous device to steer in the direction of debris.

Claims

1-2. -2. (canceled)

3. An autonomous cleaning apparatus, comprising:

a drive system operable to enable movement of the cleaning apparatus;

a controller in communication with the drive system, the controller including a processor operable to control the drive system to provide at least one pattern of movement of the cleaning apparatus; and

a debris sensor responsive to debris being collected by the apparatus for generating a debris signal indicating that the cleaning apparatus is collecting debris;

wherein the processor is responsive to the debris signal to (1) select an operative mode of the cleaning apparatus and (2) steer the cleaning apparatus toward an area containing debris.

4. The apparatus of claim 3 wherein the debris sensor comprises spaced-apart first and second debris sensing elements respectively operable to generate first and second debris signals;

and

wherein the processor is responsive to the respective first and second debris signals to select an operative mode and steer the cleaning apparatus toward an area containing debris.

5. The apparatus as in one of claims 3 or 4 wherein the debris sensor comprises a piezoelectric sensor element located proximate to a cleaning pathway of the cleaning apparatus and responsive to a debris strike to generate a signal indicative of such strike and thus of debris being collected.

26. The apparatus of claim 3 wherein the processor is operable to receive the debris signal and calculate therefrom a debris gradient, representative of changes in debris strikes and thus of changes in debris being collected, as the cleaning apparatus moves.

27. The apparatus of claim 26 wherein the processor is responsive to the sign of the debris gradient to select an operative mode.

28. The apparatus of claims 5 wherein the piezoelectric sensor element comprises a flexible piezoelectric film.

6-25. -25. (canceled)

29-33. -33. (canceled)

34. A method of operating an autonomous cleaning apparatus, the method comprising:

using a processor to control a drive system of the cleaning apparatus to provide at least one pattern of movement of the cleaning apparatus;

using a debris sensor in communication with the processor and responsive to debris being collected by the cleaning apparatus to generate a debris signal indicating that the cleaning apparatus is collecting debris; and

using the processor to respond to the debris signal to (1) select an operative mode of the cleaning apparatus and (2) steer the cleaning apparatus toward an area containing debris.

35. The method of claim 34 wherein the debris sensor responsive to debris being collected comprises spaced-apart first and second debris sensing elements respectively operable to generate first and second debris signals;

and

wherein the processor is responsive to the respective first and second debris signals to select an operative mode and steer the cleaning apparatus toward an area containing debris.

36. The method as in one of claims 34 or 35 wherein the debris sensor responsive to debris being collected comprises a piezoelectric sensor element located proximate to a cleaning pathway of the cleaning apparatus and responsive to a debris strike to generate a signal indicative of such strike.

57. The method of claims 34 wherein the processor is operable to receive the debris signal and calculate therefrom a debris gradient, representative of changes in debris strikes, as the cleaning apparatus moves.

58. The method of claim 57 wherein the processor is responsive to the sign of the debris gradient to select an operative mode.

59. The method of claims 36 wherein the piezoelectric sensor element comprises a flexible piezoelectric film.

37-56. -56. (canceled)

60-62. -62. (canceled)