Vehicle positioning or navigation utilizing associated feature pairs

Patent metadata

Field	Value
Publication number	US-10614588-B2
Application number	US-201815964192-A
Country	US
Kind code	B2
Filing date	Apr 27, 2018
Priority date	Jun 27, 2014
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A method for vehicle positioning or navigation utilizing associated feature pairs may include creating a plurality of associated feature pairs by retrieving an initial set of camera data from the camera comprising two-dimensional UV space information, forming pairs from the UV space information, and associating each pair from the UV space information with pairs from each of the plurality of three-dimensional global feature points of the industrial facility map, calculating a best estimate poses from calculated vehicle poses of the associated feature pairs, using an accumulated odometry to update the best estimate pose to a current localized position and setting a seed position as the current localized position. The navigation of the materials handling vehicle is tracked and/or navigated along the inventory transit surface navigate in at least a partially automated manner utilizing the current localized position.

First claim

The invention claimed is:

1. A materials handling vehicle comprising a camera, one or more vehicular processors, a drive mechanism configured to move the materials handling vehicle along an inventory transit surface, a materials handling mechanism configured to store and retrieve goods in a storage bay of an industrial facility, and vehicle control architecture in communication with the drive and materials handling mechanisms, wherein:
the camera is communicatively coupled to the one or more vehicular processors and captures an input image of overhead features;
an industrial facility map comprises a plurality of three-dimensional global feature points associated with a mapping of the overhead features; and
the one or more vehicular processors of the materials handling vehicle execute vehicle functions to:
(i) create a plurality of associated feature pairs by retrieving a set of camera data from the camera comprising two-dimensional UV space information, forming pairs from the UV space information, and mapping pairs from the UV space information with pairs from the plurality of three-dimensional global feature points of the industrial facility map;
(ii) calculate respective vehicle poses for associated feature pairs within a visual range of the camera;
(iii) determine a smallest pose sum error by comparing a plurality of pose sum errors of the plurality of associated feature pairs;
(iv) calculate a best estimate pose of the materials handling vehicle based on a highest-ranked pair of the plurality of associated feature pairs, wherein the highest-ranked pair comprises the smallest pose sum error of the plurality of associated feature pairs; and
(v) navigate the materials handling vehicle utilizing the best estimate pose.

2. The materials handling vehicle of claim 1 , wherein the plurality of associated feature pairs are created by data association steps comprising:
(i) creating UV space information pairs;
(ii) associating each global feature point with a first UV space feature in each UV space information pair; and
(iii) associating each global feature point within a maximum visual range of the camera with a second UV space feature in each UV space information pair.

3. The materials handling vehicle of claim 1 , wherein the calculation of a vehicle pose for each associated feature pair within a visual range of the camera is based at least in part on use of a global localization algorithm, wherein the global localization algorithm comprises a formula to calculate a yaw of the vehicle about a first UV space feature of an associated feature pair that comprises an anchored feature, wherein the formula comprises:

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Assignees

• Crown Equip Corp

Inventors

• Chandrasekar Kashyap
• Estep Ryan
• Thomson Jacob
• Waltz Lucas

Classifications

• G06T2207/30252

  Vehicle exterior; Vicinity of vehicle · CPC title

• G06F16/51

  Indexing; Data structures therefor; Storage structures · CPC title

• G06T7/73

  using feature-based methods · CPC title

• G06T2200/04

  involving 3D image data · CPC title

• G06T2207/10016

  Video; Image sequence · CPC title