Encouraging understanding and effective learning
Together with several other employees, Professor Reisgen attended the trade fair and visited the exhibition stand. One of his main aims was to find out more about current developments in electronic training systems and to compare the products on offer. "I was surprised to say the least that the systems are already up and running". Having looked at other products, it was clear to us that the Fronius system is in a class of its own, particularly in terms of ease of handling, quality and overall professionalism", was the view of Professor Reisgen. The RWTH "Science Evening" in Aachen formed the next stage, alongside the acceptance test. The Science Evening is held every two years on a Friday at various RWTH institutes, when they open their doors and offer attractive promotions on the campus sites. The ISF, run by Professor Reisgen, invited Fronius to show off its Virtual Welding simulation and training system. "The welding simulator was a real attraction for attendees. Visitors enjoyed trying out the system and the results were very suc-cessful. This response led us to expect a similarly positive reception by our trainees", the ISF head concluded. And practical experience on the institute's course of using the system has proved him right.
Every year, Professor Reisgen and his staff train between 350 and 400 students in welding techniques. Although on the course the emphasis is on teaching theory, welding expert Professor Reisgen knows from experience that, "Essentially, what students really need to grasp is the process. Say in the case of arc welding, there are so many variables that influence the quality of the weld and are partly dependent on the skill of the welder. There are anything up to 500,000 manual welders in Europe and it is these welders our engineers will be working with in the future. They need to know just how difficult it is to produce a fault-free weld seam". To this end, the ISF offers practical training exercises in small groups of four people. The time-consuming and expensive real-life exercises with electrode and TIG torch now successfully complement the virtual system.
The high level of enthusiasm shown by students helps them to learn more effectively. Even students with no previous experience of using a welding torch quickly start to develop a feel for the technique. "For them the tasks are fun, there is no fear of 'making a mess of things'. The enthusiasm is tangible. We are not able, and do not, wish to offer workshop training, but we can provide training in basic skills and understanding. For example, how body posture and torch handling can affect performance, what wire feed speeds to expect, and how the different welding parameters are inter-related. We could never do this with the materials themselves, as it would mean each student performing hundreds of welds", explained Professor Reisgen describing fur-ther aspects of the training. The high level of competition among trainees that has almost turned into a sport has also encouraged learning. Work results and students' progress are documented by the Virtual Welding system. This spurs students within and between the different groups on, leading to higher quality results.
Image and reality play an essential role in computer-based simulation and modern teaching methods, and is the reason Virtual Welding is so popular among students in Aachen. Given that there are severe limits on both welding trainer places and staffing capacity, Virtual Welding opens up opportuni-ties that would not otherwise be there. Real-life welder training workstations with extraction equipment, requires more than double the investment needed for the Virtual Welding system. On top of this comes the cost of materials, filler material and gases. Time factors are at least as significant. While in real-life welding situations, a considerable chunk of working hours is lost through changing into appropriate clothing, preparing the workplace and cleaning it up again afterwards, practically no time is lost with the Virtual Welding system.
In terms of time, the net hours spent on practice are almost the same as the gross hours. Because the virtual system is self-explanatory and intuitive to use, explanations, instructions and safety supervision are not necessary. When factors such as time saved finding suitably qualified teaching staff are taken into account, the increase in capacity and efficiency speaks for itself.
The efforts of ISF trainers and researchers to identify ways to communicate understanding of welding processes to students do not stop there. They are even looking at tools to help train the very best 'top-level' welders. This could involve practicing fault-free welding in places that are difficult to access. Or virtually testing very complex manual welding tasks in physically demanding or awkward conditions beforehand and integrating the results into electronic data-based systems for design and manufacturing processes. "Virtual Weld-ing technologies mean that the simulation of accessibility, collision, handling and welding speed, which are common features of automated and robot-assisted processes, could be transferred to manual welding processes", explains the ISF manager, looking ahead to the near future.
Professor Reisgen of the ISF at RWTH
Professor Uwe Reisgen has led the ISF, based at the Faculty of Mechanical Engineering at the RWTH University in Aachen since 2007. The "Königlich Rheinisch-Westfälische Polytechnische Schule" opened on 10 October 1870 in Aachen, with 32 teachers and 223 students on the roll. Today, the RWTH, with its 260 institutes across nine faculties, is one of the leading European business and research organisations. There are currently around 33,000 students enrolled on more than 100 courses. The ISF has been involved in modern welding and joining technologies for nearly 60 years. A key focus, alongside fundamental process analysis, is the application-oriented implementation of the knowledge gained to help (further) develop joining technologies for innovative materials and structures. The availability of a wide range of core joining technology competencies means successful solutions can be found to most joining technology problems. In total, the ISF employs 100 staff.
Virtual Welding: Simulation and training in arc-welding techniques
"Virtual Welding" provides a virtual environment for trainees to get used to the types of hand movements needed and sounds made during the process of arc-welding. It works on the basis of a tracking system. In contrast to optical tracking systems often used by game developers, Virtual Welding employs a magnetic tracking system. Using this system, even the tiniest hand movement is reproduced in a virtual world and is displayed on the screen or 3D glasses on the welder helmet. Below the workpiece, a magnetic encoder generates a spherical magnetic field. A sensor detects the position of the welding torch. The digitised signal containing the position data forms the input for the visualisation software, which evaluates the positions of the torch and workpiece. An additional sensor on the welding helmet provides a "real" view of the welding task, whether close up, from a distance or from different angles. The effect of gravity on the viscous weld metal and solidification of the metal can be seen in remarkable detail as the position of the torch relative to the workpiece changes. The typical weld seam characteris-tics resulting from the influence of different welding parameters are faithfully reproduced. In addition, the welder hears equally typical welding noises in real time. Through practice, the technical understanding of trainees - an essentially rational skill - is thus developed, alongside inextricably linked sensory perceptions.
Fronius International GmbH
Fronius International is an Austrian company with headquarters in Pettenbach, other sites in Wels, Thalheim and Sattledt, and production facilities in the Czech Republic and Ukraine. Fronius is active in the fields of battery charging systems, welding technology and solar electronics. The company employs 2,677 staff worldwide, 1,923 of whom are based in Austria. 93% of Fronius products are exported through its 14 sales subsidiaries, two agencies (Turkey/welding technology and China/solar electronics) and 130 sales partners around the world. 14.9% of the total turnover of 329 million Euro is re-invested (financial year 2009). With its outstanding products and services and 649 active patents, Fronius is world technology leader. 358 employees work in research and development.
Fronius International GmbH
Froniusplatz 1, A-4600 Wels
Tel. +43 / (0)7242 / 241 2590
Fax +43 / (0)7242 / 241 95 3940