Fixtureless component assembly

Patent metadata

Field	Value
Publication number	US-2020262078-A1
Application number	US-201916277374-A
Country	US
Kind code	A1
Filing date	Feb 15, 2019
Priority date	Feb 15, 2019
Publication date	Aug 20, 2020
Grant date	—

Abstract

A method of assembling a plurality of subcomponents to form a finished component comprises gripping a first subcomponent with a first end-of-arm tool, wherein the first end-of-arm tool is attached to a first robot arm and grasping a second subcomponent with a second end-of-arm tool, wherein the second end-of-arm tool is attached to a second robot arm. Moving the first and second end-of-arm tools to position the first subcomponent relative to the second subcomponent in a pre-assembly position and then moving the first and second end-of-arm tools to engage interface surfaces of the first and second subcomponents. Forming a joint between the first subcomponent and the second subcomponent with a joining tool attached to a joining robot arm to thereby assemble the finished component.

First claim

What is claimed is:

1 . A method of assembling a plurality of subcomponents to form a finished component, the method comprising:
grasping a first subcomponent with a first end-of-arm tool, wherein the first end-of-arm tool is attached to a first robot arm; grasping a second subcomponent with a second end-of-arm tool, wherein the second end-of-arm tool is attached to a second robot arm; moving the first and second end-of-arm tools to position the first subcomponent relative to the second subcomponent in a pre-assembly position; using a camera to visually locate the interface surfaces on the first and second subcomponents; estimating an off-set between the pre-assembly position and a required assembly position; moving the first and second end-of-arm tools to engage interface surfaces of the first and second subcomponents; moving the first and second subcomponents to the required assembly position, measuring torque forces and lateral forces placed on the first and second subcomponents by the first and second end-of-arm tools with sensors mounted on the first and second end-of-arm tools, and establishing when the first and second subcomponents are in the required assembly position based on the torque forces and lateral forces; scanning the first and second subcomponents and locating assembly datums with a non-contact measuring device; and comparing the position of the first and second subcomponents to the required assembly position.

2 . The method of claim 1 , further comprising:
after comparing the position of the first and second subcomponents to the required assembly position; forming a joint between the first subcomponent and the second subcomponent with a joining tool attached to a joining robot arm to thereby assemble the finished component.

3 . The method of claim 2 , further comprising:
after forming a joint between the first subcomponent and the second subcomponent with a joining tool attached to a joining robot arm to thereby assemble the finished component; scanning the finished component to verify geometry.

4 . The method of claim 1 , further comprising:
after scanning the first and second subcomponents and locating assembly datums with a non-contact measuring device, and comparing the position of the first and second subcomponents to the required assembly position; moving the first and second subcomponents to the required assembly position within established tolerances.

5 . The method of claim 1 , further comprising:
after scanning the first and second subcomponents and locating assembly datums with a non-contact measuring device, and comparing the position of the first and second subcomponents to the required assembly position; moving the first and second subcomponents to a thermal distortion compensation position.

6 . The method of claim 2 , further comprising:
after scanning the finished component to verify geometry; moving the first and second robot arms and plastically deforming the finished component.

7 . The method of claim 1 , wherein using a camera to visually locate the interface surfaces on the first and second subcomponents further comprises, using a fixed camera to visually locate the interface surfaces on the first and second subcomponents.

8 . The method of claim 1 , wherein using a camera to visually locate the interface surfaces on the first and second subcomponents further comprises, moving a camera mounted onto an inspection robot arm to an inspection position, and using the camera to visually locate the interface surfaces on the first and second subcomponents.

9 . The method of claim 1 , further comprising:
grasping a third subcomponent with a third end-of-arm tool, wherein the third end-of-arm tool is attached to a third robot arm; moving the third end-of-arm tool to position the third subcomponent relative to the first and second subcomponents in a pre-assembly position; using a camera to visually locate the interface surfaces on the third subcomponent; estimating an off-set between the pre-assembly position and a required assembly position; moving the third end-of-arm tools to engage interface surfaces of the first, second and third subcomponents; moving the third subcomponent to the required assembly position, measuring torque forces and lateral forces placed on the third subcomponent by the third end-of-arm tools with sensors mounted on the third end-of-arm tool, and establishing when the third subcomponent is in the required assembly position based on the torque forces and lateral forces; scanning the third subcomponent and locating assembly datums with a non-contact measuring device; and comparing the position of the third subcomponent to the required assembly position.

10 . The method of claim 9 , further comprising:
after comparing the position of the first, second and third subcomponents to the required assembly position; forming a joint between the first subcomponent and the second subcomponent with a joining tool attached to a joining robot arm and forming a joint between the second subcomponent and the third subcomponent with a joining tool attached to a joining robot arm to thereby assemble the finished component.

11 . A fixtureless component assembly system comprising:
a first robot arm having a first end-of-arm tool mounted thereon and adapted to grasp a first subcomponent; a second robot arm having a second end of arm tool mounted thereon and adapted to grasp a second subcomponent; a system controller adapted to control the first and second robot arms and first and second end-of-arm tools to position the first and second subcomponents relative to one another; an inspection camera in communication with the system controller and adapted to visually locate interface surfaces on the first and second subcomponents, wherein the system controller estimates an off-set between a pre-assembly position and a required assembly position; and sensors mounted on the first and second end-of-arm tools and adapted to measure torque forces and lateral forces placed on the first and second subcomponents by the first and second end-of-arm tools as the first and second end-of-arm tools move the first and second subcomponents to the required assembly position.

12 . The fixtureless component assembly system of claim 11 , further comprising a joining robot arm having a joining tool mounted thereon, wherein the system controller controls the joining robot arm to bring the joining tool into engagement with the first and second subcomponents and join the first and second subcomponents to one another.

13 . The fixtureless component assembly system of claim 12 , wherein the joining tool is a welding tool adapted to weld the first subcomponent to the second subcomponent.

14 . The fixtureless component assembly system of claim 11 , wherein the first and second robot arms are adapted to be controlled by the system controller based on one of position control, wherein the position of the first and second robot arms is controlled based on the three dimensional position of the robot arm within a given space, and force control, wherein the position of the first and second robot arms is controlled based on the forces placed on the first and second end-of-arm tools by the first and second robot arms as measured by the first and second force gauges.

15 . The fixtureless component assembly system of claim 11 , wherein the inspection camera is a mounted at a fixed position.

16 . The fixtureless component assembly system of claim 11 , wherein the inspection camera is mounted onto an inspection robot arm, wherein the i

Assignees

• Gm Global Tech Operations Llc

Inventors

• Saez Miguel A
• Spicer John P
• Skurkis Richard

Classifications

• G05B2219/39149

  To assemble two objects, objects manipulation · CPC title

• G05B2219/39131

  Each of the manipulators holds one of the pieces to be welded together · CPC title

• B25J9/1682 Primary

  Dual arm manipulator; Coordination of several manipulators · CPC title

• B23K37/0443 Primary

  Jigs · CPC title

• B23P19/00 Primary

  Machines for simply fitting together or separating metal parts or objects, or metal and non-metal parts, whether or not involving some deformation {(connecting metal parts or objects by metal-working procedures B21J, B23K)}; Tools or devices therefor so far as not provided for in other classes (hand tools in general B25) · CPC title