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TwiRinGo / a foldable electric bicycle


The wheels are equiped with electro-magnets.
By supplying the electromagnets with power, the wheels begin to turn. (ring motor principle)
Each time the pedal is moved forwards, the generator produces power and the TwiRinGo condenser gets recharged.
Due to both possibilities - the generator and the condenser - you donŽt have to use the pedals as much as a usual bike.
Being supplied through another technique, TwiRinGo has no need for chain and spoke.Therefore it gets possible to fold up TwiRinGo such as nearly all parts vanish inside the wheels.
Folded up, TwiRinGo measures only 38(Diameter) x 11(Thickness)cm.


Bauhaus-Universität Weimar

Bauhaus-Universität Weimar
Weimar, Germany

Prof. Heiko Bartels
Professur Produkt-Design
Bauhaus-Universität Weimar
Geschwister-Scholl-Straße 15
99423 Weimar


Hang Hoon Choi

Hang Hoon Choi
Weimar, Germany