The mAd Bike is a bicycle concept for advertising and corporate brand building purposes. Instead of making a billboard on wheels or a parade float, we set out to design a bicycle frame structure that not only conveys a message, but also serves a function.
The hydroformed sheet metal concept in Stage II required expensive tooling, which is not practical for one-offs or small series. For Stage III we designed an all-aluminium frame joined solely by adhesive bonding (no welds or mechanical joints). The key idea is to use two air bent aluminium sandwich panels which are cut with the help of 1:1 printed templates derived from the flattened sheet metal CAD model. A special head tube, seat tube and bottom bracket are machined to match the two halves and all the parts are bonded together in one step. The rear fork ends use a crushed core design stiffened with aluminium wear plates. The frame weighs 4 kg.
Acknowledgements: 3M Finland provided us with the adhesive, applicator gun, surface conditioning abrasives and wrap film.
The simple sheet metal design in Stage I managed to look different, but the ride qualities were almost non-existent and the level of finishing was too low. To use sheet metal in a more advanced manner, ideas2cycles gave a multidisciplinary team of students the task of designing a bike that showcases modern sheet metal technology. The Videbike -team created a concept for a public bike that could be used by students and staff for moving around the Aalto University campus. The flex-formed main frame is TIG-welded from 1,5 mm AW 5083 aluminium alloy. The frame weighs approximately 2 kg and the complete bike 14 kg. The project was part of the Product development project -course and the prototype was unveiled at the Product development project -gala 2011 (see video below).
How the Aalto Bike was made:
Unveiling of the Aalto Bike:
The first development stage prototype was air bent from laser cut 3 mm carbon steel and welded together. The frame weighs 7 kg and the rear fork is barely stiff enough for riding. It was designed and manufactured in three weeks by the students in the ViDeBike team. A cheap, quick and dirty prototype like this was a useful learning experience before moving on to more expensive and advanced designs seen in development Stage II (The Aalto Bike).