Robot-based roll forming

Challenge

With the expansion of vehicle manufacturers' model ranges (passenger cars, commercial vehicles) and simultaneous stagnation of total vehicle production in Europe, the quantities of sheet metal components per derivative are decreasing. The use of large and gigacast parts further reduces the demand for sheet metal parts, pushing conventional manufacturing processes (deep drawing) in press shops to an economic limit, as the high costs of component-specific forming tools can only be amortized over large quantities.

Objective The goal is to develop tool-reduced or tool-free manufacturing process chains for the economical production of sheet metal structural components. Robot-based roll forming can kinematically produce both basic shapes and secondary form elements of sheet metal structural components using universally applicable tools. These can be further adapted through functionalization, enabling a complete process chain from coil to ready-to-install, paintable components.

Social Relevance

Tomorrow's value creation requires new approaches that, among other things, enable investment-lean, agile, and highly flexible manufacturing of sheet metal structural components. Additionally, the technological approach makes significant contributions to improving sustainability. Minimizing direct material usage (approx. -20%) conserves material resources, as does the significant reduction in operating material requirements. This can lower the CO2 footprint to 10% or 1 per mill compared to conventional manufacturing methods. The technology is also capable of actively compensating for material fluctuations caused by increased use of secondary materials.

Approach / Solution

Unlike classical roll profiling or 3D roll forming with machine tools, a pair of rollers is moved as an end effector by a robot. The robot performs both the feed and the approach movements, and the rollers successively form flanges through reversing movements. The flanges can deviate from a straight edge, and the flange height or width can vary. The optical accessibility of the flange allows the realized geometry to be captured and any deviations to be detected. These can be compensated for in the next forming step, equalizing fluctuations in material quality and previous process control. The technology focuses on two key markets: in the aerospace sector, primarily aluminum wrought alloys are processed, while high-strength and ultra-high-strength steel grades are used for light commercial vehicles.