Map localizing with partially obstructed ranging devices for autonomous robots and vehicles

Number: 9943959
Published: 2018-04-17
Filed: 2016-04-25
Assignee: Disney Enterprises, Inc.
Inventors: Freeman; Kyle G.
CPC: B25J9/1664; B25J9/1697; G05D1/024; G05D1/0274; G05D1/0278
Verdict: Medium Hardware
Source: Google Patents · FreePatentsOnline

The keeper's note

Autonomous robot/vehicle SLAM with obstructed ranging.

Abstract

A method for localizing robots and other objects when ranging devices are partially obstructed. The method includes retrieving a digital map of the space and then identifying potential locations for the object in the space. The method involves generating a prediction of expected ranges between the object and surfaces in the space at each of the potential locations. The method includes operating a ranging device to measure ranges to the surfaces in the space and comparing, for each of the predictions, the measured ranges with the expected ranges to identify the most accurate prediction. The comparing includes weighting ranges that are too small neutrally as these are strikes on obstructions, weighting ranges that provide matches positively, and weighting ranges that are too large negatively, and the comparing then involves summing the weighted ranges to identify a most accurate one of the predictions and associated current location for the object.

Background

BACKGROUND1. Field of the Description(1) The present description relates, in general, to software and hardware systems for providing safe movement of autonomous objects such as robots, vehicles, and the like, and, more particularly, to a method and controller (or control system) for providing localization of an autonomous object as it moves about a space with one or more obstructions between the object and mapped objects (e.g., people milling about a robot as it moves through a mapped space defined by interior or exterior walls and other fixed objects).2. Relevant Background(2) There is a growing use of autonomous objects such as robots, vehicles, household appliances (e.g., vacuums), and so on that include an onboard controller operating in a real time manner to navigate the autonomous object about a space. It is desirable for the controller to be able to safely navigate about this space, such as a vehicle along a street, even though the space may have objects that are not fixed in location and that may obstruct the view of the autonomous object's navigational devices to fixed objects, such as building walls, defining the space.(3) For example, it may be desirable to provide a mobile robot in a space that may also be populated with many people who are moving about the space and may even be interacting with the robot. The robot may be configured to be autonomous (e.g., not under continuous manual control). For safe and/or desired movement through the space (e.g., travel along

Claims

1. A method of localizing an autonomous object in a space, comprising: retrieving from data storage a digital map of the space; with a localizing module run by a controller, identifying a plurality of potential locations for the autonomous object in the space; with the localizing module based on the digital map, generating a prediction of expected ranges between the autonomous object when at each of the potential locations and surfaces in the space, wherein the generating of the predictions includes generating a ray casting prediction from the autonomous object to the surfaces in the space; operating a ranging device to measure ranges between the autonomous object and the surfaces in the space; and comparing, for each of the predictions, the measured ranges with the expected ranges to identify one of the predictions as an accurate prediction, wherein the comparing includes weighting each of the measured ranges based on results of the comparing. 8. A localizing method, comprising: determining a plurality of potential locations of an autonomous object; from each of the potential locations, generating a ray casting prediction defining predicted ranges from the autonomous object to surfaces in a space based on a digital map of the space; measuring ranges to the surfaces in the space; identifying the measured ranges corresponding with obstructions in the space; for each of the ray casting predictions, summing all of the measured ranges except the measured ranges identified as corresponding with the obstructions; selecting one of the ray casting predictions as most accurate based on the summing; and determining localizing data for the autonomous object in the space using the selected one of the ray casting predictions. 14. An autonomous object configured for accurate localizing, comprising: a controller; a localizing module run by the controller, wherein the localizing module determines a plurality of potential locations for the autonomous object in a space and wherein the localizing module generates a prediction of expected ranges between the object and surfaces in the space for each of the potential locations; and a ranging assembly collecting ranging data about the autonomous object, wherein the localizing module compares, for each of the predictions, the ranging data with the expected ranges to identify one of the predictions as an accurate prediction, and wherein the comparing by the localizing module includes weighting measured ranges in the ranging data based on a comparison with a corresponding one of the expected ranges.