Research will start early next year on a collaborative project called NOMAD, aimed at the development of technologies to replace the assembly line-based approach to welded fabrication.
Caterpillar Belgium SA helped to initiate the project. Other key members of the team include Finnish-based Delfoi, a partner company of DELMIA, and a specialist advanced manufacturing simulation company.
The aim of the project is to develop technology that will allow "constraints free" manufacturing in which the welding process can be taken to the part, as in manual welding, instead of the part moving along an assembly line from one process to the next (as in robot welding).
This will allow fabricators to not only cope with different product designs efficiently, but to cope with varying demand by using more or fewer robots as appropriate.
The proposed system will result in the removal of human operators from hazardous fabrication environments, also making it easier to contain pollution.
Keith Herman, senior research and development engineer at Caterpillar is the project's technical co-ordinator and claims that the development was to satisfy changing customer requirements.
"In the past, our customers were happy with standard products, but now they demand customised parts that are designed specifically to match their applications," he says.
"We, like other companies, are finding it difficult to deliver these customised parts quickly and economically, with current fabrication tcchniques. At the moment, the robotic welding of customised parts is inefficient."
The reduction in the number of skilled and trained welders capable of producing these products manually, had added to the problem, according to him.
It is envisaged that the resulting system will be an automated fabrication cell capable of efficient and reduced cost production of unique, customised products.
Initially, NOMAD will concentrate on large sized steel structures but it is expected that dissemination to other industry sectors will occur before the end of the decade.
According to Heikki Aalto, executive vice president of Delfoi, "NOMAD will cut costs by automating the arc welding process, negating the need for expensive jigs."
This is because the sensor systems will identify a part and then the robot will apply the correct welding program even when they are truly customised, unique products.
"The technology should also be capable of re-vitalising traditional fabrication industries in Europe - construction, shipbuilding, off highway vehicles, structural fabrication, military vehicles and heavy handling equipment," says Aalto.
The European Commission is providing funding for the project, under the aegis of its Framework V Competitive and Sustainable Growth Program (G1RD-CT-2000-00461), Autonomous Manufacture of Large Steel Fabrications.
Delfoi and the NOMAD team will be utilising DELMIA's IGRIP as a key tool to enable the automation of robotic weld programming.
Welding information will be obtained from the CAD system simultaneously with a "weld planner", which will be especially developed as part of the project.
The position and orientation of the part to be welded will be fed into IGRIP via sensor systems.
With this information, a model of the cell will automatically be created in IGRIP, with the automatic robot programming to follow.
Other partners within the NOMAD project include Robosoft SA (France), TWI Ltd (UK), Fraunhofer IFF (Germany), Reis Robotics Robotics (Germany), ESAB AB (Sweden), and Nusteel Structures Ltd (UK).
