Robot vision-based automatic rivet placement system and method

Patent metadata

Field	Value
Publication number	US-11648604-B2
Application number	US-201917289020-A
Country	US
Kind code	B2
Filing date	Oct 8, 2019
Priority date	Jul 10, 2019
Publication date	May 16, 2023
Grant date	May 16, 2023

Abstract

A robot vision-based automatic rivet placement system and method. The automatic rivet placement system includes: an industrial robot installed on a frame, a multi-functional end effector, a rivet blowing mechanism, a detection disk, and a rivet holding tray. The multi-functional end effector consists of a flange disk, a support frame, an industrial CCD camera, a laser displacement sensor, a spring, a mixing rod, and a vacuum nozzle. The multi-functional end effector is connected to a terminal end of the industrial robot via the flange disk. The industrial CCD camera is installed directly in front of the support frame, and is used to acquire a rivet image and measure a rivet parameter. The laser displacement sensor is installed at a side surface of the support frame, and is used to measure a rivet depth.

First claim

The invention claimed is:

1. A robot vision-based automatic rivet placement system, comprising: an industrial robot ( 1 ), a multi-functional end effector ( 2 ), a cover plate component ( 3 ), a rivet blowing mechanism ( 4 ), a detection disk ( 5 ), a vacuum generator ( 6 ), a valve group ( 7 ), a control cabinet ( 8 ), a frame ( 9 ), a rivet holding tray ( 10 ) and an industrial personal computer ( 11 ), wherein
the industrial robot ( 1 ), the cover plate component ( 3 ), the rivet blowing mechanism ( 4 ), the detection disk ( 5 ), the vacuum generator ( 6 ), the valve group ( 7 ) and the rivet holding tray ( 10 ) are installed on the frame ( 9 );
the multi-functional end effector ( 2 ) is composed of a flange disk ( 12 ), a support frame ( 13 ), an industrial CCD camera ( 14 ), a laser displacement sensor ( 15 ), a spring ( 16 ), a mixing rod ( 17 ) and a vacuum nozzle ( 18 );
the multi-functional end effector ( 2 ) is connected to a terminal end of the industrial robot ( 1 ) via the flange disk ( 12 );
the support frame ( 13 ) is used to fix elements on the multi-functional end effector ( 2 );
the industrial CCD camera ( 14 ) and the laser displacement sensor ( 15 ) form a rivet space pose measurement module, wherein the industrial CCD camera ( 14 ) is installed directly in front of the support frame ( 13 ) and is used to acquire a rivet image;
the laser displacement sensor ( 15 ) is installed on a side surface of the support frame ( 13 ) and is used to measure a rivet depth;
the spring ( 16 ) and the mixing rod ( 17 ) form an elastic mixing mechanism and is used to mix the rivet holding tray ( 10 ); and
the vacuum nozzle ( 18 ) is installed below the support frame ( 13 ) and is used to pick up or place a rivet.

2. The robot vision-based automatic rivet placement system according to claim 1 , wherein the cover plate component ( 3 ) is composed of a guide rail component ( 19 ), a first connecting piece ( 20 ), a rivet feeding tube ( 21 ), a cover plate ( 22 ), a pneumatic sliding table ( 23 ), a limiting block ( 24 ) and a second connecting piece ( 25 );
the first connecting piece ( 20 ) is used to connect the guide rail component ( 19 ) and the cover plate ( 22 ); the second connecting piece ( 25 ) is used to connect the pneumatic sliding table ( 23 ) and the cover plate ( 22 ); and the limiting block ( 24 ) is used to limit a position of the cover plate ( 22 ).

3. The robot vision-based automatic rivet placement system according to claim 2 , wherein the rivet feeding tube ( 21 ) is located directly below the cover plate ( 22 ); and
when the pneumatic sliding table ( 23 ) pushes out the cover plate ( 22 ), an inner hole of the rivet feeding tube ( 21 ) is aligned with a rivet inlet hole of the cover plate ( 22 );
and when the pneumatic sliding table ( 23 ) withdraws the cover plate ( 22 ), the inner hole of the rivet feeding tube ( 21 ) is sealed by the cover plate ( 22 ).

4. The robot vision-based automatic rivet placement system according to claim 3 , wherein the cover plate ( 22 ) is provided with four holes having different diameters; and edges of the four holes are respectively welded with arc-shaped opening retainer rings.

5. The robot vision-based automatic rivet placement system according to claim 2 , wherein the rivet blowing mechanism ( 4 ) is composed of an air pipe fast connector ( 26 ), a valve core ( 27 ), a valve body ( 28 ), a pipe clamp ( 29 ), sealing rings ( 31 ), a rivet placement pipe ( 32 ), a floating connector ( 33 ), and an air cylinder ( 34 ), wherein the valve core ( 27 ), the sealing rings ( 31 ) and the valve body ( 28 ) form a valve of the rivet blowing mechanism ( 4 ).

6. The robot vision-based automatic rivet placement system according to claim 5 , wherein the air pipe fast connector ( 26 ) is connected to a left end of the valve core ( 27 );
the floating connector ( 33 ) connects a right end of the valve core ( 27 ) and a piston rod of the air cylinder ( 34 );
the pipe clamp ( 29 ) connects the valve body ( 28 ) and the rivet placement pipe ( 32 );
the rivet feeding tube ( 21 ) is installed at an upper end of the valve body ( 28 ); and
two sealing rings ( 31 ) are respectively sleeved in two grooves of the valve core ( 27 ).

7. The robot vision-based automatic rivet placement system according to claim 6 , wherein the valve core ( 27 ) is of an elongate cylindrical structure; the valve core ( 27 ) is provided with an air path channel and a rivet channel; and the air path channel is connected to the air pipe fast connector ( 26 ).

8. The robot vision-based automatic rivet placement system according to claim 2 , wherein the detection disk ( 5 ) is composed of an air blowing nozzle ( 35 ), an air nozzle support frame ( 36 ), an acrylic plate ( 37 ), a light source support frame ( 39 ), a backlight source ( 40 ), a hollow round disk ( 41 ), a baffle plate ( 42 ) and a waste box ( 43 );
the acrylic plate ( 37 ) and the hollow round disk ( 41 ) are fixed above a table plate ( 38 ) and directly opposite to the backlight source ( 40 ); and the baffle plate ( 42 ) and the waste box ( 43 ) are placed on a right side of the hollow round disk ( 41 );
the air nozzle support frame ( 36 ) is used to fix the air blowing nozzle ( 35 ) on the hollow round disk ( 41 ), and the light source support frame ( 39 ) is used to fix the backlight source ( 40 ) below the table plate ( 38 ).

9. The robot vision-based automatic rivet placement system according to claim 1 , wherein the detection disk ( 5 ) is composed of an air blowing nozzle ( 35 ), an air nozzle support frame ( 36 ), an acrylic plate ( 37 ), a light source support frame ( 39 ), a backlight source ( 40 ), a hollow round disk ( 41 ), a baffle plate ( 42 ) and a waste box ( 43 );
the acrylic plate ( 37 ) and the hollow round disk ( 41 ) are fixed above a table plate ( 38 ) and directly opposite to the backlight source ( 40 ); and the baffle plate ( 42 ) and the waste box ( 43 ) are placed on a right side of the hollow round disk ( 41 );
the air nozzle support frame ( 36 ) is used to fix the air blowing nozzle ( 35 ) on the hollow round disk ( 41 ), and the light source support frame ( 39 ) is used to fix the backlight source ( 40 ) below the table plate ( 38 ).

10. The robot vision-based automatic rivet placement system according to claim 1 , wherein 35 rivet holding trays ( 10 ) are provided in total, and are arranged in five rows and seven columns.

Assignees

• Univ Nanjing Aeronautics & Astronautics

Inventors

• Tian Wei
• Zheng Yi
• Zhuang Zhiwei
• Liao Wenhe
• Zhang Lin
• Li Bo
• Hu Junshan

Classifications

• B21J15/32 Primary

  Devices for inserting or holding rivets in position with or without feeding arrangements · CPC title

• B25J19/022

  using lasers · CPC title

• B21J15/26 Primary

  operated by rotary drive, e.g. by electric motor · CPC title

• B23P19/007

  Picking-up and placing mechanisms · CPC title

• B25J11/007

  Riveting · CPC title