Object gripping apparatus, method of controlling the same and storage medium

Patent metadata

Field	Value
Publication number	US-9302391-B2
Application number	US-201113312976-A
Country	US
Kind code	B2
Filing date	Dec 6, 2011
Priority date	Dec 15, 2010
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

An object gripping apparatus includes an image capturing unit for capturing a region including a plurality of works, an obtaining unit for obtaining distance information of the region, a measurement unit for measuring three-dimensional positions/orientations of a plurality of gripping-candidate works out of the plurality of works based on the image and distance information, thereby generating three-dimensional position/orientation information, a selection unit for selecting a gripping-target work based on the three-dimensional position/orientation information, a gripping unit for gripping the gripping-target work, and an updating unit for updating the three-dimensional position/orientation information by measuring three-dimensional positions/orientations of the gripping-candidate works at a time interval during gripping of the gripping-target work. When the gripping ends, the next gripping-target work is selected based on the updated three-dimensional position/orientation information of the gripping-candidate works.

First claim

What is claimed is:

1. An information processing apparatus comprising:
an obtaining unit adapted to obtain distance information of a region including a plurality of objects;
a first selection unit configured to select a plurality of holding candidate objects from the plurality of objects based on the distance information;
a measurement unit adapted to measure three-dimensional position and orientation information of the selected plurality of holding candidate objects based on the distance information;
a second selection unit adapted to select a holding target object from the plurality of holding candidate objects and select one or more tracking target objects other than the selected holding target object from the plurality of holding candidate objects, based on the three-dimensional position and orientation information measured by said measurement unit;
a controlling unit adapted to cause a holding unit to hold the holding target object; and
an updating unit adapted to update the three-dimensional position and orientation information of the tracking target objects by obtaining a visible image including the tracking target objects at a predetermined time interval during holding of the holding target object by said holding unit without obtaining distance information newly, wherein the update by said updating unit is performed by a different method from the measurement by said measurement unit,
wherein when the holding by said holding unit has ended, said second selection unit selects a next holding target object based on the three-dimensional position and orientation information of the tracking target objects updated by said updating unit, wherein the updating unit updates the three-dimensional position and orientation information of the tracking target objects so that a difference between a position in the visible image where registered model data of the tracking target objects is projected to the position of the target tracking objects in the visible image decreases.

2. The apparatus according to claim 1 , wherein
when the holding by said holding unit has ended, and the three-dimensional position and orientation information of the tracking target objects updated by said updating unit have not varied from the three-dimensional position and orientation information of the tracking target objects measured by said measurement unit,
said second selection unit selects the next holding target object from the tracking target objects based on the three-dimensional position and orientation information measured by said measurement unit without obtaining distance information newly.

3. The apparatus according to claim 1 , wherein
when the holding by said holding unit has ended and the three-dimensional position and orientation information of the tracking target objects updated by said updating unit have varied from the three-dimensional position and orientation information of the tracking target objects measured by said measurement unit,
said obtaining unit obtains distance information in the predetermined range including the target objects anew, based on the three-dimensional position and orientation information of the tracking target objects updated by said updating unit,
said measurement unit measures the three-dimensional positions and orientations of the tracking target objects anew based on the distance information and generates three-dimensional position and orientation information anew, and
said second selection unit selects the next holding target object from the tracking target objects based on the anew measured three-dimensional position and orientation information.

4. The apparatus according to claim 1 , further comprising:
a storage unit adapted to store three-dimensional geometric information of said holding unit; and
a calculation unit adapted to calculate, based on the three-dimensional geometric information stored in said storage unit, for each holding target object, a shielding ratio representing a ratio of an area of the holding candidate objects shielded by said holding unit to an area of the holding candidate objects when not shielded by said holding unit,
wherein said second selection unit selects the holding target object from the holding candidate objects, based on the three-dimensional position and orientation information measured by said measurement unit and the shielding ratio.

5. The apparatus according to claim 4 , wherein said second selection unit selects, as the holding target object, a holding candidate object with the smallest shielding ratio.

6. The apparatus according to claim 1 , wherein said updating unit updates the three-dimensional positions and orientations of the holding candidate objects that exist within a predetermined range from the holding target object.

7. The apparatus according to claim 1 , further comprising
a unit adapted to obtain a visible image including the plurality of objects;
wherein said measurement unit measures the three-dimensional positions and orientations of the holding candidate objects based on the visible image and the distance information.

8. The apparatus according to claim 1 , wherein said updating unit obtains the image data of the tracking target objects without obtaining distance information of the tracking target objects anew.

9. A method of controlling an information processing apparatus, the method comprising:
obtaining distance information of a region including a plurality of objects;
selecting a plurality of holding candidate objects from the plurality of objects based on the distance information;
measuring three-dimensional position and orientation information of the selected plurality of holding candidate objects based on the distance information;
selecting a holding target object from the plurality of holding candidate objects and select one or more tracking target objects other than the selected holding target object from the plurality of holding candidate objects, based on the three-dimensional position and orientation information measured in the measuring;
holding the holding target object; and
updating the three-dimensional position and orientation information of the tracking target objects by obtaining a visible image including the tracking target objects at a predetermined time interval during holding of the holding target object in the gripping without obtaining distance information newly, wherein the updating is performed by a different method from the measurement,
wherein in the selecting, when the holding in the holding step has ended, a next holding target object is selected based on the three-dimensional position and orientation information of the tracking target objects updated in the updating, wherein in the updating, the three-dimensional position and orientation information of the tracking target objects is updated so that a difference between a position in the visible image where registered model data of the tracking target objects is projected to the position of the target tracking objects in the visible image decreases.

10. A non-transitory computer-readable storage medium storing a computer program that causes a computer to execute steps of an object gripping apparatus control method, the method comprising:
obtaining distance information of a region including a plurality of objects;
selecting a plurality of holding candidate objects from the plurality of objects based on the distance information;
measuring three-dimensional position and orientation information of the selected plurality of holding candidate objects based on the distance information;
selecting a holding target object from the plurality of holding candidate objects and select one or more tracking target objects other than the selected ho

Assignees

• Iio Yuichiro
• Mitarai Yusuke
• Canon Kk

Inventors

• Iio Yuichiro
• Mitarai Yusuke

Classifications

• B25J9/1697

  Vision controlled systems · CPC title

• G06T1/0014

  Image feed-back for automatic industrial control, e.g. robot with camera (robots B25J19/023) · CPC title

• G05B2219/40053

  Pick 3-D object from pile of objects · CPC title

• B25J9/1679 Primary

  characterised by the tasks executed · CPC title