Robotic Arc Welding Requirements Functionality

(1) A more advanced seam tracking system will decrease resources needed for programming. In the general case, this will allow the sensor to guide the robot from start to end with only a small number of intermediate poses in the case of complex weld joints. Naturally, the sensor guidance must include orientation as well as this is an important parameter to obtain defined quality and productivity.

(2) In cases where the sensor detects a change of orientation of the weld joint, the welding torch must be oriented at a specific angle relative the joint to produce the weld in accordance with the welding specification procedure. This procedure defines the conditions to comply with quality requirements and the torch orientation is as important as many other parameters to control.

Robotic Arc Welding in Future Trends

Robot systems for automation of welding are today a robust technology that combines productivity with quality in a variety of designs of robot stations. The technology is combined with a set of supporting techniques related to welding engineering (different processes, control of the welding process, etc.), sensor technology and simulation and programming. New welding processes such as rapid arc and laser welding will put further demands on control aspects on robot systems as the travel speed increases and process operating parameters become more narrow. The use of new production processes is however linked to product design and the preparation of robust programs for the Robotic Arc Welding station so that the benefits of new processes can be utilized to their optimum.

Robotic Arc Welding Developments for Higher Autonomy

Research and development work on industrial robots goes back to the 1950s when developments took place in the field of NC machine tools. These machines had many building blocks in common with robots and the first prototype of an industrial robot from Unimation saw the light of day in 1960, and was in operation at Ford in 1961. The robots at the time were relatively simple with so called Point To Point (PTP) control and were primarily used in materials handling and machine tending, with spot welding coming shortly after for Robotic Arc Welding.

Still in the 1960s, Trallfa (now ABB Robotics) developed a robot for spray painting. The concept of programming and control of such a robot was quite different. The principle was that the programmer grabbed the robot end-effector and moved it in space and time while the robot recorded the motions. Typically, many such programs with quite short cycle times were made in a short time and the best one was selected for production. The method turned out to be a practical solution for the application in mind. It was tested on other applications as well in the 1970s, including arc welding, but with less success.