Systems and methods for correction of drift via global localization with a visual landmark

A computer-readable medium having instructions for autonomous localization and mapping, the computer-readable medium comprising:

• a module with instructions configured to visually observe an environment via a visual sensor;
• a module with instructions configured to maintain a map of landmarks in a data store, where the map of landmarks is based at least in part on visual observations of the environment;
• a module with instructions configured to receive data from a dead reckoning sensor, where the dead reckoning sensor relates to movement of the visual sensor within the environment;
• a module with instructions configured to use data from the dead reckoning sensor and a prior pose estimate to predict a new device pose in a global reference frame at least partly in response to a determination that a known landmark has not been encountered;
• and
• a module with instructions configured to use data from the visual sensor to predict a new device pose in the global reference frame at least partly in response to a determination that a known landmark has been recognized, where the new device pose estimate is based at least in part on a previous pose estimate associated with the known landmark, and using the visual sensor data to update one or more maps.

A method of localization and mapping in a mobile device that travels in an environment, the method comprising:

• receiving images of the environment from a visual sensor coupled to the mobile device as the mobile device travels in the environment;
• extracting visual features from one or more images;
• matching at least a portion of the visual features to previously observed features;
• estimating one or more poses of the mobile device relative to the previously-observed sets of features based at least in part on matches found between features observed in the image and features previously observed;
• using the one or more estimated relative poses to localize the mobile device within one or more maps;
• and
• updating the one or more maps.

A circuit for localization and mapping in a mobile device that travels in an environment, the circuit comprising:

• a circuit configured to receive images of the environment from a visual sensor coupled to the mobile device as the mobile device travels in the environment;
• a circuit configured to extract visual features from one or more images;
• a circuit configured to match at least a portion of the visual features to previously-observed features;
• a circuit configured to estimate one or more poses of the mobile device relative to the previously-observed sets of features based at least in part on matches found between features observed in the image and features previously observed;
• a circuit configured to use the one or more estimated relative poses to localize the mobile device within one or more maps;
• and
• a circuit configured to update the one or more maps.

A computer-readable medium having instructions for localization and mapping in a mobile device that travels in an environment, the computer-readable medium comprising:

• a module with instructions configured to receive images of the environment from a visual sensor coupled to the mobile device as the mobile device travels in the environment;
• a module with instructions configured to extract visual features from one or more images;
• a module with instructions configured to match at least a portion of the visual features to previously-observed features;
• a module with instructions configured to estimate one or more poses of the mobile device relative to the previously-observed sets of features based at least in part on matches found between features observed in the image and features previously observed;
• a module with instructions configured to use the one or more estimated relative poses to localize the mobile device within one or more maps;
• and
• a module with instructions configured to update the one or more maps.

A method of autonomous localization, the method comprising:

• observing a visually-identifiable landmark that is not referenced in a data store;
• storing an estimated pose corresponding to when the visually-identifiable landmark was observed;
• storing references to the visually-identifiable landmark such that a relative pose to the landmark can be calculated when the visually-identifiable landmark is re-observed;
• using dead reckoning data for navigation between observations of visually-identifiable landmarks;
• and
• using a visual observation of a landmark with a reference in a global reference frame to adjust the estimate of a pose so as to reduce an amount of drift in a pose later estimated with the dead reckoning data.

A circuit for autonomous localization, the circuit comprising:

• a circuit adapted to observe a visually-identifiable landmark that is not referenced in a data store;
• a circuit adapted to store an estimated pose corresponding to when the visually-identifiable landmark was observed;
• a circuit adapted to store references to the visually-identifiable landmark such that a relative pose to the landmark can be calculated when the visually-identifiable landmark is re-observed;
• a circuit configured to use dead reckoning data for navigation between observations of visually-identifiable landmarks;
• and
• a circuit configured to use a visual observation of a landmark with a reference in a global reference frame to adjust the estimate of a pose so as to reduce an amount of drift in a pose later estimated with the dead reckoning data.

A computer-readable medium having instructions for autonomous localization, the computer-readable medium comprising:

• a module with instructions configured to observe a visually-identifiable landmark that is not referenced in a data store;
• a module with instructions configured to store an estimated nose corresponding to when the visually-identifiable landmark was observed;
• a module with instructions configured to store references to the visually-identifiable landmark such that a relative nose to the landmark can be calculated when the visually-identifiable landmark is re-observed;
• a module with instructions configured to use dead reckoning data for navigation between observations of visually-identifiable landmarks;
• and
• a module with instructions configured to use a visual observation of a landmark with a reference in the global reference frame to adjust the estimate of a pose so as to reduce an amount of drift in a pose later estimated with the dead reckoning data.

A circuit for autonomous localization, the circuit comprising:

• a means for observing a visually-identifiable landmark that is not referenced in a data store;
• a means for storing an estimated pose corresponding to when the visually-identifiable landmark was observed;
• a means for storing references to the visually-identifiable landmark such that a relative pose to the landmark can be calculated when the visually-identifiable landmark is re-observed;
• a means for using dead reckoning data between observations of visually-identifiable landmarks;
• and
• a means for using a visual observation of a landmark with a reference in the global reference frame to adjust the estimate of a pose such that an amount of drift in a pose later estimated with the dead reckoning data is substantially reduced.

A method of autonomous localization and mapping, the method comprising:

• receiving images from a visual sensor;
• receiving data from a dead reckoning sensor;
• generating a map based on landmarks observed in the images, where a landmark is associated with a device pose as at least partly determined by data from the dead reckoning sensor, where the landmarks are identified by visual features of an unaltered or unmodified environment and not by detection of artificial navigational beacons;
• storing references to the landmarks such that a relative nose to a landmark can be calculated when the landmark is re-observed;
• and
• localizing within the map by using a combination of recognition of visual features of the environment and dead reckoning data.

A computer-readable medium having instructions for autonomous localization and mapping, the computer-readable medium comprising:

• a module with instructions configured to receive images from a visual sensor;
• a module with instructions configured to receive data from a dead reckoning sensor;
• a module with instructions configured to generate a map based on landmarks observed in the images, where a landmark is associated with a device pose as at least partly determined by data from the dead reckoning sensor, where the landmarks are identified by visual features of an unaltered or unmodified environment and not by detection of artificial navigational beacons;
• a module with instructions configured to store references to the landmarks such that a relative pose to a landmark can be calculated when the landmark is re-observed;
• and
• a module with instructions configured to localize within the map by using a combination of recognition of visual features of the environment and dead reckoning data.

A method of adding a landmark to a map of landmarks, the method comprising:

• using visual features observed in an environment as landmarks;
• referencing poses for landmarks in a map of landmarks in a global reference frame;
• storing one or more coordinates of the landmark's 3-D features in the landmark reference frame;
• and
• storing an initial estimate of landmark pose.

A computer-readable medium having instructions for adding a landmark to a map of landmarks, the computer-readable medium comprising:

• a module with instructions configured to use visual features observed in an environment as landmarks;
• a module with instructions configured to reference poses for landmarks in a map of landmarks in a global reference frame;
• a module with instructions configured to store one or more coordinates of the landmark's 3-D features in the landmark reference frame;
• and
• a module with instructions configured to store an initial estimate of landmark pose.