Coordinated robot to robot component assembly

Patent metadata

Field	Value
Publication number	US-10899012-B2
Application number	US-201916277350-A
Country	US
Kind code	B2
Filing date	Feb 15, 2019
Priority date	Feb 15, 2019
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

A method of assembling a secondary component to a primary component comprises grasping a primary component with a first end-of-arm tool, wherein the first end-of-arm tool is attached to a first robot arm and grasping a secondary component with a second end-of-arm tool, wherein the second end-of-arm tool is attached to a second robot arm. Moving the primary component to an interfacing position, wherein interfacing surfaces on the primary component are presented at a proper position and orientation for the secondary component to be attached thereto. Moving the second end-of-arm tool to bring the secondary component into engagement with the interface surfaces of the primary component, and forming a joint between the primary component and the secondary component with a joining tool attached to a joining robot arm.

First claim

What is claimed is:

1. A method of assembling a secondary component to a primary component, the method comprising:
grasping a primary component with a first end-of-arm tool, wherein the first end-of-arm tool is attached to a first robot arm;
grasping a secondary component with a second end-of-arm tool, wherein the second end-of-arm tool is attached to a second robot arm;
visually inspecting the primary component with a camera mounted on the second end-of-arm tool;
locating at least one datum feature on the primary component;
comparing the location of the at least one datum feature of the primary component, as measured by the camera, to a reference coordinate frame stored in a second controller, wherein the second controller is adapted to control movements of the second robot arm and second end-of-arm tool;
calculating an off-set between the location of the at least one datum feature of the primary component, as measured by the camera, and the reference coordinate frame;
registering the off-set information in the second controller;
sending the off-set information stored in the second controller to a first controller over a robot-to-robot communication architecture; wherein the first controller is adapted to control movements of the first robot arm and first end-of-arm tool;
creating a coordinate frame in the first controller based on the off-set information received from the second controller;
moving the primary component to an interfacing position, wherein interfacing surfaces on the primary component are presented at a proper position and orientation for the secondary component to be attached thereto;
sending the created coordinate frame, including the position of the at least one datum feature after moving the primary component, from the first controller to the second controller;
using the created coordinate frame and the position of the at least one datum feature to identify the location of the interface surface for the secondary component on the primary component relative to the at least one datum feature based on the created coordinate frame; and
moving the second end-of-arm tool to bring the secondary component into engagement with the interface surfaces of the primary component.

2. The method of claim 1 , further comprising, forming a joint between the primary component and the secondary component with a joining tool attached to a joining robot arm.

3. The method of claim 2 , wherein forming a joint between the primary component and the secondary component with a joining tool attached to a joining robot arm further comprises:
welding the secondary component to the primary component with a welding tool attached to the joining robot arm.

4. The method of claim 1 , further comprising:
simultaneously with moving the second end-of-arm tool to bring the secondary component into engagement with the interface surfaces of the primary component;
monitoring forces measured by a force gauge mounted on the second robot arm, wherein the force gauge is adapted to measure forces being placed onto the secondary component by the second robot arm and second end-of arm tool to determine when there is contact between the primary and secondary components and to measure the force that the secondary component is being held in contact with the primary component.

5. The method of claim 4 , further comprising:
simultaneously with forming a joint between the primary component and the secondary component with a joining tool attached to a joining robot arm;
continuously monitoring forces measured by the force gauge mounted on the second robot arm; and
varying the position between the primary component and the secondary component to achieve a pre-determined force schedule.

6. The method of claim 4 , further comprising:
simultaneously with forming a joint between the primary component and the secondary component with a joining tool attached to a joining robot arm;
continuously monitoring forces measured by the force gauge mounted on the second robot arm to detect thermal distortion between the primary component and secondary component; and
varying the position and force applied between the primary component and the secondary component in reaction to thermal distortion between the primary component and secondary component.

7. The method of claim 1 , wherein moving the primary component to an interfacing position, wherein interfacing surfaces on the primary component are presented at a proper position and orientation for the secondary component to be attached thereto further comprises:
moving the first robot arm and first end-of-arm tool, and simultaneously, moving the primary component with respect to the first end of arm tool, to move the primary component to an interfacing position, wherein interfacing surfaces on the primary component are presented at a proper position and orientation for the secondary component to be attached thereto.

8. The method of claim 7 , wherein moving the primary component with respect to the first end of arm tool, further comprises:
articulating a trunnion mounted on the first end-of-arm tool, wherein the trunnion supports the primary component within the first end-of-arm tool and is moveable with a single degree of freedom to rotate the primary component relative to the first end-of-arm tool.

9. The method of claim 1 , wherein visually inspecting the primary component further comprises:
visually inspecting the primary component with a camera mounted on the second end-of-arm tool.

10. The method of claim 1 , wherein visually inspecting the primary component further comprises:
visually inspecting the primary component with a camera mounted at a fixed location.

11. A component assembly system comprising:
a first end-of-arm tool mounted onto a first robot arm, wherein the first end-of-arm tool is adapted to grasp a primary component;
a second end-of-arm tool mounted onto a second robot arm, wherein the second end-of-arm tool is adapted to grasp a secondary component;
a non-contact inspection device adapted to visually inspect the primary component and locate datum features on the primary component;
a first controller adapted to control movements of the first robot arm;
a second controller adapted to control movements of the second robot arm and to compare the location of the datum features of the primary component, as measured by the inspection device, to a reference coordinate frame stored in the second controller, wherein the second controller is further adapted to calculate an off-set between the location of the datum features of the primary component, as measured by the camera, and the reference coordinate frame, and to register the off-set information in the second controller;
a robot-to-robot communication architecture interconnecting the first controller and the second controller, wherein the second controller sends the off-set information to the first controller over the robot-to-robot communication architecture, wherein the first controller is adapted to create a coordinate frame based on the off-set information received from the second controller and move the primary component to an interfacing position, wherein interfacing surfaces on the primary component are presented at a proper position and orientation for the secondary component to be attached thereto; and
a force gauge mounted onto the second end-of-arm tool, wherein the force gauge is adapted to measure reaction forces in the interface surfaces when there is contact between the primary and secondary components.

12. The component assembly system of claim 11 , further comprising:
a joining tool mounted onto a joining robot arm, wherein the joining tool is adapted to

Assignees

• Gm Global Tech Operations Llc

Inventors

• Saez Miguel A
• Spicer John P

Classifications

• B25J9/1628

  characterised by the control loop · CPC title

• B25J13/085

  Force or torque sensors (B25J13/082, B25J13/084 take precedence) · CPC title

• B25J9/1697

  Vision controlled systems · CPC title

• B25J9/1687 Primary

  Assembly, peg and hole, palletising, straight line, weaving pattern movement · CPC title

• B25J15/0019

  End effectors other than grippers · CPC title