3-D robotic welding simulation benefits
Cover Story: Teaching robots how to weld using 3-D simulation is beneficial because welding is a complex, precise process that cannot be explained or taught easily to humans.
Elements of advanced motion control, 3-D vision, and robotic control combine in 3-D simulation software for robotic welding. The future in robotic welding is digital and simulation helps show possibilities that might not have been considered before.
Genesis Systems Group uses simulation to visualize and demonstrate complex or large-scale robotic processes before anything is built. This is especially helpful for welding, which is a complex, precise process that cannot be easily explained or taught to humans.
The 3DG Environment at the Genesis Systems Group Virtual Solutions Center is designed to combine virtual reality and immersive 3-D visualization to visualize a robotic process in the concept and design phases. The 3DG technology is designed to ergonomically evaluate parameters such as welding torch access and robot reach. The system consists of a 16-panel audiovisual wall that displays 2-D and 3-D images. It’s also portable, which makes it easy to dismantle and set up.
"It’s a great tool for us," said Brendan Brown, virtual solutions engineer at Genesis Systems Group. "With the 3DG Environment, we’re able to draw clients into the experience and give them a real-life feel for what they will get with one of our systems. They get to see what we do upfront and all the pre-order work we do to give them the right solution."
They also use the 3DG system to conduct reviews with their in-house design and tooling groups for a collaborative process.
"You wear a set of regular 3-D glasses like you would get at a movie theatre," Brown said. "Then with the joystick, you can drive around the model, to go around the machine, get underneath it, come inside, and look at it from all angles."
For example, a welding robot on a three-axis gantry is positioned to MIG weld the frame of a large dump truck used in the mining industry and the multicolored sections represent the part.
"Some of these parts are 40 feet long," Brown said. "This part requires multi-pass, heavy thick-plate welding. It’s a 48-hour cycle time to weld one piece. This part actually grew 2- to 3-in. during the welding process just because of the heat and draw on it (distortion)."
Brown said the simulation environment allows them to demonstrate advanced processes to their clients that they may not have imagined were feasible. The automotive and appliance industries are starting to take a closer look at laser welding.
"We won a handful of customer orders because we were able to laser weld, which has a lot less heat and distortion. We’ve done simulations to show them. One gentleman in my department does strictly weld distortion and heat analysis. He can show a customer how with traditional MIG welding on a certain part you might have 5 mm of draw or deflection in it, but with laser welding it’s down to 1 mm."
Laser welding benefits
Across the hall from their Virtual Solutions Center is Genesis’ Automated Solutions Center, where they test technologies such as remote laser welding and a laser seam stepper.
Genesis is using the robotic laser seam stepper to test customers’ parts that have been traditionally spot-welded. They also have a few robotic systems already in the field.
The laser seam stepper is a servo-driven, self-contained laser head. "One of the advantages is that you don’t need the large laser safety cabinets common with most laser welding processes," Brown said. "The robot will move above the part, then drive the laser head down, basically applying force with the head, which helps push the two materials together. Then it runs a bead up to 40 mm in length. You don’t need the giant light-tight enclosure, and a lot less fixturing is involved. It’s a much better finish than a traditional spot weld and certainly more consistent."
Brown said advanced welding technologies such as remote laser welding and the laser seam stepper still prompt the same concerns for part fit-up and other critical variables as do conventional welding processes. The process still has to be understood in its entirety to successfully automate it.
Tanya M. Anandan is contributing editor for the Robotic Industries Association (RIA) and Robotics Online. RIA is a not-for-profit trade association dedicated to improving the regional, national, and global competitiveness of the North American manufacturing and service sectors through robotics and related automation. This article originally appeared on the RIA website. The RIA is a part of the Association for Advancing Automation (A3), a CFE Media content partner. Edited by Chris Vavra, production editor, Control Engineering, CFE Media, firstname.lastname@example.org.
- 3-D simulation can be used to teach robots how to weld.
- Teaching laser welding to robots can reduce distortion and deflection and improve accuracy overall.
- While robots can be taught how to weld, humans need to have a strong understanding of the process.
What other benefits can come from teaching robots how to weld?