Debris sensor for cleaning apparatus

• US 8,598,829 B2
• Filed: 06/14/2012
• Issued: 12/03/2013
• Est. Priority Date: 01/28/2004
• Status: Expired due to Term

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Landry, Gregg W., Cohen, David A., Ozick, Daniel N.
• Primary Examiner(s): Ip, Paul
• Application Number:
  US13/523,109
• Publication Number:
  US 20120246862A1
• Time in Patent Office: 537 Days
• Field of Search: 318/567, 318/580, 318/568.12, 318/587, 153/19, D15/319, D15/377, 700/245, 700/253, 700/258, 382/153, 901/1, 901/46
• US Class Current: 318/587
• 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. An autonomous cleaning apparatus comprising:

a side brush;

a main brush;

a debris bin;

a chassis carrying the side brush, the main brush, and the debris bin, the side brush operative to direct particulates from a cleaning surface toward the main brush, and the main brush operative to direct the particulates toward the debris bin;

a piezoelectric sensor disposed between the main brush and the debris bin, wherein impact of the particulates moving from the side brush to the main brush toward the debris bin is detectable by the piezoelectric sensor;

a drive system carried by the chassis and operative to move the chassis; and

a control module coupled to the piezoelectric sensor and configured control the drive system based on the detected impact of the particulates moving from the side brush to the main brush toward the debris bin.

2. The autonomous cleaning apparatus of claim 1, wherein the chassis defines a perimeter and the side brush is arranged to entrain particulates outside the perimeter of the chassis.

3. The autonomous cleaning apparatus of claim 1, the drive system operative to move the chassis along a fore-aft axis dividing the chassis into substantially symmetrical right and left halves, wherein the side brush is disposed on the right half or the left half of the chassis, along a forward portion of the chassis.

4. The autonomous cleaning apparatus of claim 3, wherein the side brush is disposed on a dominant side of the cleaning apparatus.

5. The autonomous cleaning apparatus of claim 3, wherein the main brush is on the right half and the left half of the chassis and rearward of the sidebrush.

6. The autonomous cleaning apparatus of claim 3, wherein the chassis defines a vacuum inlet, and the main brush is disposed forward of the vacuum inlet.

7. The autonomous cleaning apparatus of claim 3, wherein the debris bin is disposed rearward of the main brush and the debris bin is removable from the chassis.

8. The autonomous cleaning apparatus of claim 3, wherein the drive system is configured to adjust movement of the cleaning apparatus based at least in part on a signal representative of debris impact on the piezoelectric sensor.

9. The autonomous cleaning apparatus of claim 1, further comprising a counter-rotating flapper carried by the chassis, the counter-rotating flapper meeting the main brush such that the counter-rotating flapper and the main brush direct the particulates toward the debris bin.

10. The autonomous cleaning apparatus of claim 1, wherein the main brush and the piezoelectric sensor define an axis therebetween and the main brush is operable to move the particulates along the axis in a direction toward the piezoelectric sensor.

11. The autonomous cleaning apparatus of claim 1, wherein the piezoelectric sensor is above the main brush as the cleaning apparatus moves along the cleaning surface.

12. The autonomous cleaning apparatus of claim 1, further comprising a processor operable to process a signal from the piezoelectric sensor indicative of a particulate strike to generate a signal representative of a quantity or volumetric parameter of the particulates.

13. An autonomous cleaning apparatus comprising:

a drive system comprising a right wheel assembly and a left wheel assembly, each wheel assembly comprising a respective motor;

a side brush;

a main brush;

a debris bin;

a chassis carrying the drive system, the side brush, the main brush, and the debris bin, the side brush operative to direct particulates from a cleaning surface toward the main brush, and the main brush operative to direct the particulates toward the debris bin;

a control module configured control the drive system; and

a debris sensor disposed between the main brush and the debris bin, wherein the particulates directed by the side brush to the main brush toward the debris bin are detectable by the debris sensor, and the control module is configured to adjust movement of the cleaning apparatus based at least in part on a signal representative of the particulates detected by the debris sensor.

14. The autonomous cleaning apparatus of claim 13, wherein a speed of one or both of the right and left wheel assemblies is changeable based at least in part on a signal representative of the particulates detected by the debris sensor.

15. The autonomous cleaning apparatus of claim 13, wherein the drive system is configured to steer the chassis based at least in part on a signal representative of the particulates detected by the debris sensor.

16. The autonomous cleaning apparatus of claim 13, further comprising a processor operable to process a signal from the debris sensor to generate a signal representative of a quantity or volumetric parameter of the particulates.