08253368 is referenced by 14 patents and cites 1310 patents.

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.

Title
Debris sensor for cleaning apparatus
Application Number
12/687436
Publication Number
8253368 (B2)
Application Date
January 14, 2010
Publication Date
August 28, 2012
Inventor
Daniel N Ozick
Newton
MA, US
David A Cohen
Brookline
MA, US
Gregg W Landry
Gloucester
MA, US
Agent
Fish & Richardson P C
Assignee
iRobot Corporation
MA, US
IPC
G05D 1/00
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