Linkage system for prehending objects using impactive forces

Patent metadata

Field	Value
Publication number	US-11247347-B2
Application number	US-202016799600-A
Country	US
Kind code	B2
Filing date	Feb 24, 2020
Priority date	Sep 20, 2019
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

Aspects described herein include an end effector capable of prehending items using impactive and astrictive forces. The end effector includes an interface system having a deformable mounting plate and a pliable body member attached to the mounting plate. The end effector further includes a linkage system between a plurality of actuators and the interface system. The linkage system connects to lateral portions of the mounting plate.

First claim

What is claimed is:

1. An end effector capable of prehending items using impactive and astrictive forces, the end effector comprising:
a central structural member arranged around a central axis of the end effector;
a plurality of actuators;
an interface system comprising:
a deformable mounting plate; and
a pliable body member attached to the mounting plate, the pliable body member having, at a distal end, a sealing surface configured to seal with items brought into proximity with the end effector, the pliable body member at least partially defining an inner recess;

a vacuum port in fluid communication with the inner recess and arranged around the central axis; and
a linkage system between the plurality of actuators and the interface system, the linkage system comprising, for each actuator of the plurality of actuators:
a first link connected with:
an end of the actuator at a first joint, the first joint at a first radial distance from the central axis; and
the central structural member via a second joint, the second joint at a second radial distance less than the first radial distance; and

a second link connected with:
the first link at a third joint, the third joint at a third radial distance greater than the first radial distance; and
a lateral portion of the mounting plate at a fourth joint, the fourth joint at a fourth radial distance greater than the third radial distance.

2. The end effector of claim 1 , wherein the plurality of actuators comprises:
a first pair of opposing linear actuators within a first plane; and
a second pair of opposing linear actuators within a second plane orthogonal to the first plane.

3. The end effector of claim 1 , wherein at least one component of the linkage system is rotatable about a rotation axis to cause the mounting plate to rotate about the central axis.

4. The end effector of claim 3 , wherein the first link comprises:
a first link component; and
a second link component rotatable relative to the first link component.

5. The end effector of claim 3 , wherein the linkage system further comprises, for each actuator of the plurality of actuators:
an intermediate member connected with the first link at the second joint,
wherein the intermediate member is rotatable relative to the central structural member.

6. A method of prehending an item using an end effector, the method comprising:
bringing the item into proximity of a sealing surface at a distal end of a pliable body member;
applying a suction force to an inner recess defined within the pliable body member, thereby causing the end effector to apply an astrictive force to the item; and
applying, using a plurality of actuators connected with lateral portions of a deformable plate through a linkage system, at least a first force to deform the deformable plate and cause the end effector to apply an impactive force to the item.

7. The method of claim 6 , wherein the end effector applies the impactive force to the item prior to applying the suction force to the inner recess.

8. The method of claim 6 , further comprising:
prior to contacting the item with the sealing surface, applying at least a second force using the plurality of actuators to deform the deformable plate and alter a geometry of the sealing surface.

9. The method of claim 6 ,
wherein at least one component of the linkage system is rotatable about a rotation axis to cause the deformable plate to rotate about a central axis of the end effector, and
wherein contacting the item with the sealing surface causes the at least one component to rotate such the sealing surface is more closely aligned with a geometry of the item.

10. The method of claim 6 ,
wherein the plurality of actuators comprises linear actuators,
wherein applying the first force comprises extending a first linear actuator of the plurality of actuators to apply the first force to a first joint of a first link,
wherein applying the first force causes the first link to rotate about a second joint that connects the linkage system with a central structural member of the end effector,
wherein rotating the first link about the second joint causes a second force to be applied to a third joint connecting the first link with a second link, and
wherein applying the second force to the third joint causes a third force to be applied to a fourth joint connecting the second link with a first lateral portion of the lateral portions.

11. The method of claim 10 ,
wherein the first joint is at a first radial distance from a central axis of the end effector,
wherein the second joint is at a second radial distance less than the first radial distance,
wherein the third joint is at a third radial distance greater than the first radial distance, and
wherein the fourth joint is at a fourth radial distance greater than the third radial distance.

12. An end effector for prehending items, the end effector comprising:
a plurality of actuators;
an interface system comprising a deformable plate; and
a linkage system between the plurality of actuators and the interface system, the linkage system comprising, for each actuator of the plurality of actuators:
a first link connected with:
an end of the actuator at a first joint, the first joint at a first radial distance from a central axis of the end effector; and
a central structural member via a second joint, the second joint at a second radial distance less than the first radial distance; and

a second link connected with:
the first link at a third joint, the third joint at a third radial distance greater than the first radial distance; and
a lateral portion of the deformable plate at a fourth joint, the fourth joint at a fourth radial distance greater than the third radial distance,

wherein at least one component of the linkage system is rotatable about a rotation axis to cause the deformable plate to rotate about the central axis.

13. The end effector of claim 12 ,
wherein the plurality of actuators comprises linear actuators,
wherein extending at least two opposing linear actuators of the plurality of actuators causes the deformable plate to deform, and
wherein the deformable plate, when deformed, causes the end effector to apply an impactive force to an item.

14. The end effector of claim 13 , wherein the interface system further comprises:
a pliable body member attached to the deformable plate and having a sealing surface at its distal end configured to seal with items brought into proximity with the end effector, the pliable body member at least partially defining an inner recess, and
wherein the end effector further comprises a vacuum port in fluid communication with the inner recess.

15. The end effector of claim 14 , wherein the vacuum port is arranged around the central axis.

16. The end effector of claim 12 , wherein the linkage system further comprises, for each actuator of the plurality of actuators:
an intermediate member connected with:
the first link at the second joint;
an exterior of the actuator via a fifth joint, the fifth joint at a fifth radial distance greater than the second radial distance; and
the central structural member via a sixth joint,

wherein the rotation axis is the rotation axis of the sixth joint.

17. The end effector of claim 16 , wherein the fifth joint is at a sleeve arranged around the actuator, the sleeve configured to rotate about the actuator.

18. The end effector of claim 16 , wherein the rotation axis of the sixth joint is substantially parallel to the central axis of the end effector.

Assignees

• Amazon Tech Inc

Inventors

• Wellman Parris S
• Marcus Beth A
• Coleman Gregory
• Nambi Manikantan
• Aduh Erica
• Dietz Timothy G
• Lilliston Iii Leonard Thomas
• George Margaret Jean Williams
• Eichenberger Jonas
• Moser Mathias
• Ernst Dominique
• Schlaepfer Ueli

Classifications

• B25J9/123

  Linear actuators · CPC title

• B66C1/68

  mounted on, or guided by, jibs (jibs B66C23/64) · CPC title

• B25J9/1612

  characterised by the hand, wrist, grip control · CPC title

• B25J15/0683 Primary

  Details of suction cup structure, e.g. grooves or ridges · CPC title

• G05B2219/39557

  Vacuum gripper using mask with pattern corresponding to workpiece to be lifted · CPC title