The Bionic Bike was presented at the Hannover Messe 2015 as an outstanding development success in functional 3D printing. The bike, whose frame was developed from scratch using the ELiSE process and manufactured by citim GmbH from an aluminium alloy using the laser beam melting process, demonstrates the advantages of the ELiSE lightweight construction process in combination with additive manufacturing methods such as the functional integration of lighting and cable routing or the production of complex geometries to stiffen edges and surfaces. The elimination of welding seams also results in a uniform material structure.
The possibilities of additive manufacturing provide previously unattained freedom in shaping. Hollow structures can be adapted to local loads at specific points and can be stiffened with lattice structures designed to withstand loads. Algorithms specially developed for this purpose are available. For example, the Bionic Bike benefits from the stiffening by adaptive lattice structures in the area of the highly loaded bottom bracket. The result: 60% weight reduction and a unique design.
The following classical engineering methods and bionic development tools of the ELiSE process were combined in the development of the Bionic Bike:
- Topology optimization to determine optimal load paths
- Parametric optimization based on evolutionary algorithms to design the ideal frame geometry with variable cross-sectional shapes
- CAO for minimizing notch stress
- Structural stiffening by means of adaptive beam structures at highly stressed areas inside the structure
- Integration of bionic principles based on the model of lightweight structures of the shells of diatoms