Rob O’Connell
12/9/2025
PSU 7 213
Robotic Welding
Robotic welding is the process of using an automated robotic arm that manipulated a
welding gun to join metal pieces. It has many benefits over traditional welding as far as safety,
production, and quality control. The first robotic welder, the UNIMATE, was used by General
Motors in 1962. It was developed by George Devol, Joseph Engelberger and the Unimation
company. Since then, the technology has been developed to where AI software programs the
robots and handles much of the coding of the motors and welder. This topic has always interested
me because I have done a lot of welding myself and would one day like to set up or even build a
robotic welder.
The first robotic welders were used for spot welding in the GM automobile production
lines. This was a dangerous and tedious task for manual welding, leading to quality issues,
injuries, and low productivity. The UNIMATE robot changed all of that, paving the way for a
safer, more productive future. By the 1980’s, other companies like Kuka, Motoman, and Fanuc
started manufacturing robots for spot welding, but they were expensive and difficult to set up.
They still saved so much time and effort that by 2006, over 60,000 robots were working
throughout America. These early robots were purely pre-programmed by skilled software
engineers and coders who had to have extensive knowledge in welding and coding. The robots
could not deal with any variation in parts because there was no feedback loop to readjust the
weld path if parts were out of alignment. This made robots only a good investment for massive
automobile factories to use in high volume, simple parts.
The first welding process that these robots performed was spot welding. This process
joins two parallel sheets of metal by applying pressure with two contacts on both sides of the
sheets and then sending a high amperage electric current through to fuse the metal. There is no
filler metal, so parts must be completely clean to avoid porosity and week weldments. Using this
process, it is hard to reach into tight corners or far from the edge of the part. Later, robots
expanded to arc welding, which uses a filler metal and electric arc to melt and fuse materials.
The most common arc welding process is MIG, or metal inert gas, which uses a power source,
wire feeder, and an inert shielding gas around the weld. The circuit is completed through the wire
that feeds out of a gun at the end of the robot’s arm, through the part, and returns to the power
Rob O’Connell
12/9/2025
PSU 7 213
source through the ground clamp. An extremely hot arc forms where the wire contacts the part,
depositing the filler metal as a weld as the wire is fed in. The wire speed, voltage, and gas flow
must be tuned perfectly to get the right size and penetration of weld for that specific part. Other
less common forms of robotic welding include TIG, SAW, and LBW. As robots are becoming
more advanced with more axes and controllability, they can weld extremely complex parts very
quickly.
Today, hundreds of companies manufacture robotic welders and software systems to run
them. New advancements are always being made, including using AI based vision systems to
look at a part, create a weld path and execute it with little or no human input. New processes like
laser beam welding (LBW) are being developed and have massive benefits as far as cost and
productivity. This process uses a laser beam that wiggles back and forth over filler metal. It is
fast and strong and does not warp parts as much as arc welding because there is less heat input.
The most recent software lets you add welds in the 3D modelling stage and automatically
programs the robot to weld it according to your parameters. Cameras and laser guidance systems
look for any variation in parts and adjust the position of the weld to fit perfectly. Some systems
even check weld quality and adjust the temperature of the weld as it goes. While all this software
capability is out there, it can still be difficult to set up and run smoothly because there are so
many variables.
The productivity and versatility of robotic welders is increasing exponentially. Not only
can they work around the clock, but they are getting faster, safer, and more customizable. This
allows companies to do smaller runs of parts, conforming with JIT production principles. The
complex robotic arms paired with moving jigs and fixtures allow for single step weld procedures
on extremely complex assemblies that formerly may have needed multiple steps and jigs to weld.
Some ethical issues have been discussed as well with robots. There is the fear that they
will take coveted jobs in the industry, but I think this is not a problem. Manual welding will
always be necessary for repairs of single parts where setting up a robot is impractical. More jobs
are being created designing and setting up. Robots also work better alongside humans, using
tracking software that pauses the robot if someone is too close. These are known as Cobots, for
their ability to work alongside humans.
Rob O’Connell
12/9/2025
PSU 7 213
References
[1] E. Cole, “Industrial Automation’s Biggest Challenges: Welding in Complex Environments,”
Automate.org, Dec. 20, 2024. [Online]. Available:
https://www.automate.org/robotics/industry-insights/automation-challenge-weldingcomplex-environments. Accessed: Dec. 11, 2025.
[2] “What Is Robotic Welding and How Does It Work?,” VPIC Group. [Online]. Available:
https://www.vpic-group.com/blog/what-is-robotic-welding-and-how-does-it-work.
Accessed: Dec. 11, 2025.
[3] “The Evolution of Robotic Welding — A Historical Retrospective,” Robots.com. [Online].
Available: https://www.robots.com/articles/the-evolution-of-robotic-welding-a-historicalretrospective. Accessed: Dec. 11, 2025.
[4] “MIG Welding: Techniques, Advantages, and Applications,” ESAB University. [Online].
Available: https://esab.com/us/nam_en/esab-university/blogs/mig-welding-techniquesadvantages-and-applications/. Accessed: Dec. 11, 2025.