Presented on the 12th Latin American Robotics Symposium - Uberlândia - MG - Brazil

1. A VBM System for Inteligent
Robotic Welding
MEng. Cristiano Steffens, Eng. Bruno Quaresma, Eduardo Leivas,
Eng. Jusoan Mór, Márcio Aguiar, Sidnei Filho, Valquiria Hüttner,
Prof. Dr. Silvia Botelho, Prof. Dr. Vagner Rosa
Federal University of Rio Grande – FURG
Computational Sciences Center – C3
2015

2. Organization
• About the Nautilus-BOT project
• Welding Robot
• Welding power source and wire feeder
• Machine Vision
• FPGA

3. About
• The Nautilus project
o Innovation, scientific and technologic development on Brazilian naval
construction and offshore industry
o Work on different steps of the process of constructing a dockyard
o Multidisciplinary teams
• The Nautilus-BOT project
o A subproject of the Nautilus project
o Aims to enhance the welding process and product quality via automation
and robotization

4. Typical Setup of a Linear Welding System
Welding System

5. The BUG-O MDS Welding Robot
MDS Robot, BUG-O System. Source: BUG-O Systems

6. The BUG-O MDS Welding Robot
• Robust Modular Robot
o Rails and Carriages
o Linear Weaver
o Pendulum Weaver
• Can be used on a large variety of surfaces
• Able to make different welding seams
• Weldor adjusts the linear rail and the parameters in runtime

7. The BUG-O MDS Welding Robot
Bent Rigid Rail
Source: BUG-O Systems
Rigid and Semi-flex Rail
Source: BUG-O Systems

8. The BUG-O MDS Welding Robot
Seam Pattern
Source: BUG-O Systems
Welding Groove

9. BUG-O Systems ECX-B 0021
Parts Representation of BUG-O MDS. Source: Bug-O Systems

10. Welding power source and wire feeder
• Lincoln Flextec 450 multi-process welder
o Stick, DC TIG, MIG, Flux-Cored, Arc Gouging welds
o Factory and field operation (portable)
o Voltage and amperage control
• Lincoln Linc Feed 33 wire feeder
o Feedback system on the wire drive guarantees consistent speed
o Controls wire and protection gas
o Can be controled via Flextec 450
• Remote control module

11. Welding power source and wire feeder
Welding Power Source
Sorce: Lincoln Electric
Wire Feeder.
Sorce: Lincoln Electric

12. Machine Vision System
• Groove measurement and modeling
• Custom LED lighting system
• Terasic D5M Camera + Altera D0-Nano
• Full control of the camera registers
• HW & SW integration
• USB and Bluetooth communication
• Embeded image processing

13. Machine Vision System
Altera DE0-Nano.
Source: Altera
Camera Terasic D5M.
Source: Altera
Illumination Circuitry

14. Machine Vision System
Image Acquisition Setup Welding Groove Properties

15. Processing in the VBM system
Line Segment DetectionHDR Input Images

16. Machine Vision System (SW)
• Contrast enhancement
• Noise reduction
• Edge and line detection
• Heuristics
• Pixel to metric unit conversion
• Welding equipment settings

17. FPGA Based Control
Early Stages of the Pinout Mapping

18. Results (Measured x Ground-truth)
Ground-truth VBM Output
Property Average Std. Dev. Average. Std. Dev
Gap A 19.950 0.184 19.916 0.342
Gap B 6.706 0.275 6.557 0.295

19. Results (Uncertainty)
Property Average value Standard Deviation
Gap A 19.523 0.227
Gap B 6.222 0.111

20. What has been done after?
• Tests on more specimens
• Robot control improvements (positioning and weaving)
• Multi-exposure composition
• + Noise removal filters
• + Line detection algorithms

21. What has been done after?

22. What’s next?
• Modularization
o Robot control
o Power source and wire feed control
o VBM system
• Runtime recognition of the groove dimensions and welding
• Weld quality evaluation

23. A VBM System for Inteligent
Robotic Welding
cristianosteffens@furg.br
Federal University of Rio Grande – FURG
Computational Sciences Center – C3