Page 38 - Welding Robots Technology, System Issues, and Applications

Welding Robots
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empty ones. That operation is done periodically with the help of electro-
mechanical fork-lift-trucks.

Most of the features presented for this example will be explored in this book for
robotic welding applications, namely the capacity to simulate the procedure, the
capacity to adjust on-line and change parameterization, the capacity to monitor the
system, the database like way of specifying sequence of operations, etc.

1.3.2 Are Robots Adapted to Robotic Welding?

From the presented example it is evident that using robots in actual manufacturing
setups is a choice for flexibility, agility, a way to reduce cost and increase quality.
The modern world produces a huge variety of products that include welding in
their manufacturing processes, which means that also welding could benefit from
the introduction of robot manipulators. But are actual robots adapted for robotic
welding?

Basically actual robot manipulators include the following features:

1. Programmable control system, using powerful programming languages and
environments.
2. It is possible to define positions/orientations, define reference systems,
parameterize trajectories and other actions, and play that continuously with
high precision and repeatability.
3. Advanced PLC capabilities are also available, namely, IO control and data
acquisition, and several communication interfaces and protocols. These
functionalities enable robots to coordinate actions with other equipments
and sensors, and being integrated with other computers and manufacturing
systems existing in the setup.

The most important characteristics of actual robot manipulators are summarized in
Table 1.1.

Since most welding techniques require motion control, sensor integration and
coordination with the welding power source (controlled using IO digital and analog
signals, or fieldbuses), then robot manipulators are an almost perfect match for the
vast majority of welding processes. Difficulties may also arise in automating the
welding process, namely using robots. In fact, introducing robots means increasing
complexity in the manufacturing process, and requires skilled personnel to handle
programming and maintenance. That may constitute a major drawback, not
allowing companies to take full advantage from the flexibility stored inside the
robotic manufacturing machines. This puts focus on human-machine interfaces
(HMI) for control, command and supervision, leaving space for the software
architecture used to develop the HMI solutions.