German automotive development company, Edag Engineering, has created a bionically optimised sports car structure using hybrid manufacturing and laser technology.
The Edag Light Cocoon, which was premiered at the Geneva Motor Show in 2015 and won a 2016 German Design Award, demonstrates the latest in lightweight construction techniques. The car frame is covered with a weatherproof textile outer skin, which is backlit to give a veined pattern.
The vehicle structure was engineered in collaboration with Laser Zentrum Nord, additive manufacturing firm Concept Laser, and the BLM Group, an Italian laser cutting machine provider.
The Light Cocoon frame is a combination of intelligently processed steel profiles fixed in place by additively manufactured 3D nodes - connecting structures functioning a bit like brackets. The nodes are produced as required for each vehicle, while the profiles are cut to the appropriate shape and length, initially using 3D bending and then with 2D and 3D laser cutting.
The focus is on joining together individual components to create a hybrid structure. The components are laser welded with a fillet weld on the lap joint.
The additively manufactured nodes can be adapted to reflect each load stage, for example by incorporating additional stiffening elements to cater for high load requirements.
Edag Engineering devised the frame concept, the laser welding was carried out by Laser Zentrum Nord, the BLM Group undertook 3D bending and laser cutting, and Concept Laser made the nodes with its LaserCusing additive process.
The nodes were produced on an X line 1000R machine from Concept Laser, which has a build envelope of 630 x 400 x 500mm3 and operates a 1kW laser.
The nodes are built around a support structure, which absorbs internal stresses and prevents the component from warping.
The basic idea of the Light Cocoon is to have a node/profile design that can be customised to reflect the needs of the particular car model. By employing processes that do not involve many tools, the aim is to manufacture all bodywork versions economically and flexibly.