Robotic Specialists
By Ola Svanstrom and Nicholas Sheble
Robots are multi-talented. They perform a number of different tasks with high precision, high speed, and heavy loads.
When a specific task—and only this task—is required, it makes sense to use a customized version of the multi-functional robot. An example of this highly specialized expert robot is one that sorts different goods with very high speed. Spot welding in the automotive industry is another example where talented “professionals” are of high value.
Reach under car frame
Modern assembly lines for car manufacturing are chock full of robots.
Most of these robots look like the ones we expect to see: They have a long arm with a “hand” that can bend forward and backward and turn around like a golfer in a full swing.
However, there are other mechanical movement systems in place that normally would not be what we call “robots,” even though they work in a way similar to their more prominent relatives. These robots can weld, grip, move, lift, sort, paint, grind, or hold parts of a car together to help other robot colleagues perform different tasks in an optimal way.
For a car manufacturer, it makes sense to install multi-talented robot types because they can handle so many different tasks without making major adjustments.
When we look at the automotive support robots that join parts, it turns out the majority of them today are there for thermal welding. Thermal welding can use one of several technologies: conventional spot welding, laser welding, and laser soldering or friction steer welding. Regardless of the specific technology, the same robot can operate the thermal joining mechanism.
Ten years from now, thermal welding technology will likely still be dominant when compared to mechanical joining or chemical methods. Given this trend, and the growing requests from the automotive industry for higher flexibility and lower cost, it makes sense to complete the portfolio of robots in an assembly line with specialized welders.
The latest welding technology is multi-talented and light. It is more compact than previous machines, and it saves valuable space in the production line, which allows the hosting of two welding specialists—one may be hanging from the ceiling or mounted on a second working level in relation to the moving car body.
Its agility is such that it can actually reach under a car frame to perform less accessible welding operations.
System with three light arms
Robot controllers have made gains too, and they allow for coordinated movement of several robots and simultaneous working on the same piece. If the new agile welding robot connects to such a system, other robots can position the work piece for welding.
Due to the flexible mounting of these welding robots, several of them can handle a car body at the same time and even reach below or into the car without disturbing each other.
Safe movement concepts ensure a collision-free operation at all times.
While the robot-specialists dance around the car body and weld with high speed in all corners, the multitalented mechanic can concentrate on the manifold other operations.
This combination of generalists and specialists opens up manufacturing to radically new concepts. Through this achievement, respot lines get shorter and faster with eight robots working simultaneously.
The assembly of body sides and roofs becomes more flexible and faster when spot welders and power robots help each other. This increased flexibility is highly appreciated by the automotive industry.
It supports the trend to manufacture more car models on the same line, which not only speeds up the process but also enables optimal use of the valuable assets in the production line. A modern assembly line cannot effectively work without specialists that support the multi-talented robots.
There are specialists for quite different applications. One is a picking robot that is a system with three very light arms and a gripper that can lift and transport light items such as chocolate pieces or pralines and sort them into boxes. Some robots would be too slow for this even though they could perform more functions in the sorting process.
The concept of specialist robots is gaining ground in industry.
Whenever mass production of parts is required, a specialist may very well be the more flexible and economic
solution.
ABOUT THE AUTHORS
Ola Svanström (ola.svanstrom@ch.se.abb.com) is a 20-year veteran and manager at ABB Robotics. He has a M.Sc. in mechanical engineering and an MBA. Nicholas Sheble (nsheble@isa.org) is senior technical editor at InTech.