Method for determining at least one mechanical property of at least one object

Patent metadata

Field	Value
Publication number	US-11514589-B2
Application number	US-201915733383-A
Country	US
Kind code	B2
Filing date	Jan 21, 2019
Priority date	Jan 19, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

The invention relates to a method and a device for determining at least one mechanical property of at least one object,wherein the at least one object is subjected to at least one interaction which influences a movement state of the at least one object,wherein the at least one interaction is selected such that the movement state effectuated by the interaction is a function of the at least one mechanical property,wherein the at least one object is observed using at least one camera,wherein the movement state is determined from images recorded by the at least one cameraand wherein the at least one mechanical property of the at least one object is determined from the movement state thus determined.

First claim

The invention claimed is:

1. A method for determining at least one mechanical property of at least one object, the method comprising:
subjecting the at least one object to at least one interaction which influences a movement state of the at least one object, wherein the at least one interaction is selected such that the movement state effectuated by the interaction is a function of the at least one mechanical property;
observing the at least one object using at least one camera, wherein the at least one object is recorded multiple times at different times by the at least one camera; and
determining the movement state from images recorded by the at least one camera, wherein the at least one mechanical property of the at least one object is determined from the movement state thus determined;
wherein for the at least one object the movement state is determined from at least one of an average velocity or an average acceleration of the at least one object, wherein at least one of the average velocity of the at least one object is averaged over a maximum period of time which the object is visible in the at least one recorded image or the average acceleration of the at least one object is averaged over a maximum period of time which the at least one object is visible in the at least one recorded image.

2. The method according to claim 1 , wherein at least one interaction with the object is generated, which effectuates a change of a movement state of the at least one object.

3. The method according to claim 1 , wherein the at least one object is recorded using at least two cameras from different directions.

4. The method according to claim 1 , wherein the at least one object is recorded using a first camera at a first point in time and using a second camera at a second point in time, which is different from the first.

5. The method according to claim 1 , wherein for the at least one object the movement state is further respectively determined as a set containing one or more selected from:
a minimum velocity in the period of time which the respective object is visible in the at least one recorded image;
at least one of a maximum velocity in the period of time which the respective object is visible in the at least one recorded image, or an average velocity over a part of the period of time in which the at least one object is visible in the at least one recorded image;
a minimum acceleration in the period of time which the at least one object is visible in the at least one recorded image; and
at least one of a maximum acceleration in the period of time which the at least one object is visible in the at least one recorded image or an average acceleration over a part of the period of time in which the at least one object is visible in the at least one recorded image.

6. The method according to claim 1 , wherein the interaction comprises at least one of an application of vibration of at least one impact, an interaction with a contact surface, or an interaction with an airflow.

7. The method according to claim 1 , wherein the at least one object, for the subjection to the at least one interaction, is at least one of vibrated using a vibrating table, translated on a slide or a stepped slide or a sandblasted, brushed or coated slide, or is moved using a conveyor belt.

8. The method according to claim 1 , wherein the at least one mechanical property comprises at least one of an inertia, a mass, a density, a friction with a surrounding medium, a rolling capacity, an adhesion, a stiffness, a modulus of elasticity, a coefficient of reconstitution, or a flow resistance of the object.

9. The method according to claim 1 , wherein the images are subjected to at least one of:
image processing, image correction, segmentation, localization, or feature computation, to determine the movement.

10. The method according to claim 1 , wherein at least one mechanical property is determined jointly of a plurality of objects.

11. The method according to claim 1 , wherein at least a portion of the at least one object is identified and tracked in different ones of the images, wherein the tracking is preferably performed using at least one of:
multi object tracking or extended object tracking.

12. The method according to claim 11 , wherein the movement of the objects at least one object is described by a list of at least one center-of-gravity measurement.

13. The method according to claim 1 , wherein the movement is ascertained from the images recorded by the at least one camera using a neural network, wherein firstly the neural network is trained using a set of objects having known properties, and subsequently the at least one property of the at least one object detected in the images are determined using the neural network.

14. The method according to claim 10 , wherein the at least one object is classified with the aid of the at least one mechanical property.

15. The method according to claim 1 , wherein at least one geometrical property of the at least one object is determined.

16. The method according to claim 1 , wherein the method is utilized for at least one of measurement or classification in at least one of:
an industrial test, an inspection for bulk goods sorting, or for piece goods testing.

17. A device for determining at least one mechanical property of at least one object, comprising:
at least one interaction device for subjecting the at least one object to an interaction which influences a movement state of the object;
at least one camera, using which the at least one object is observable, wherein the at least one object is recorded multiple times at different times by the at least one camera; and
at least one analysis unit, using which the at least one mechanical property of the at least one object is determinable from images recorded by the camera, wherein the at least one mechanical property is determined from a movement state of the at least one object determined from images recorded by the at least one camera, and wherein for the at least one object the movement state is determined from at least one of an average velocity or an average acceleration of the at least one object, wherein at least one of the average velocity of the at least one object is averaged over a maximum period of time which the object is visible in the recorded images or the average acceleration of the at least one object is averaged over a maximum period of time which the at least one object is visible in the recorded images.

Assignees

• Fraunhofer Ges Forschung
• Karlsruher Institut Fuer Tech Kit
• Fraunhofer Gesellshaft Zur Foerderung Der Angewandten Forschung E V
• Karlsruber Institut Fuer Tech

Inventors

• Längle Thomas
• Noack Beniamin
• Pfaff Florian
• Hanebeck Uwe
• Gruna Robin
• Maier Georg

Classifications

• B07C5/3422

  using video scanning devices, e.g. TV-cameras · CPC title

• B07C5/342 Primary

  according to optical properties, e.g. colour {(according to radiation transmittivity B07C5/3416)} · CPC title

• G06T7/292 Primary

  Multi-camera tracking · CPC title

• G06T2207/20084

  Artificial neural networks [ANN] · CPC title