Steven C Alexander

US Patent:

20110082585, Apr 7, 2011

Filed:

Aug 31, 2010

Appl. No.:

12/873018

Inventors:

Boris SOFMAN - Pittsburgh PA, US
Vladimir ERMAKOV - Santa Clara CA, US
Mark EMMERICH - San Jose CA, US
Steven ALEXANDER - Fremont CA, US
Nathaniel David MONSON - Mountain View CA, US

Assignee:

NEATO ROBOTICS, INC. - Mountain View CA

International Classification:

G06F 19/00
G06F 15/00
G06G 7/48

US Classification:

700259, 700258, 702150, 700245, 703 6

Abstract:

Techniques that optimize performance of simultaneous localization and mapping (SLAM) processes for mobile devices, typically a mobile robot. In one embodiment, erroneous particles are introduced to the particle filtering process of localization. Monitoring the weights of the erroneous particles relative to the particles maintained for SLAM provides a verification that the robot is localized and detection that it is no longer localized. In another embodiment, cell-based grid mapping of a mobile robot's environment also monitors cells for changes in their probability of occupancy. Cells with a changing occupancy probability are marked as dynamic and updating of such cells to the map is suspended or modified until their individual occupancy probabilities have stabilized. In another embodiment, mapping is suspended when it is determined that the device is acquiring data regarding its physical environment in such a way that use of the data for mapping will incorporate distortions into the map, as for example when the robotic device is tilted.