Collision & Friction
Collision & Friction

Collision & Friction

Experts: Mathew Aitchison (Architecture), Norbert Koch (Physics), Ernesto Marceca (Chemistry), Wolfgang Schäffner (Cultural History and Theory)

Participants: Ashley Paine (Architecture), Santiago Di Lella (Biological Chemistry), Rolfe Bart (Design / Architecture), Carla Farrugia (Cultural History and Theory)


In urban space, the encounter of diverse mobile and immobile elements is highly organised. Just consider for example the U-Bahn (or underground) and the strict organisation of its movements: different tracks, doors open and close, people hop on and off. Nonetheless, when mobile objects meet in urban space, they may collide or friction may be caused on surfaces and interfaces.

Research Problem & Questions

Cars crash. A traffic jam is the consequence. U-Bahn and S- Bahn trains get cancelled and people have to wait at the stations. These two examples illustrate collisions and frictions, which commonly affect urban mobility systems in a negative way; they disrupt smooth processes. At KOSMOS 2012, the interdisciplinary research team turned this understanding upside down and took “Collision & Friction” as productive force. Instead of thinking collision and friction as facets of urban mobility that should always be avoided, the participants focussed on possible productive aspects and new ways of coordination.


The research process of the participants was supported by impulse lectures of different experts from Cultural History and Theory as well as Physics. Visiting Tempelhof airport, currently one of the most important and vivid spaces where urban development takes place in Berlin, encouraged the participants to grasp some political and social aspects of urban mobility planning in addition to academic approaches.

Research process & results

Berlin’s public transport system causes disruptions and requires passengers to put up with long transfers as well as waiting times. It was exactly these circumstances that gave rise to the concept of Flow City. The research team took “Collision & Friction” in urban space as their starting point to develop a new model of public transport. Calling upon disciplinary backgrounds ranging from Architecture to Chemistry the participants generated a model of an intelligent, user-oriented urban transport system called Flow City. It transforms the structure of single tracks and sections of Berlin’s current traffic system into one consistent network. Smaller and automated vehicles are used in order to enable passengers to reach their destinations directly and without time-consuming transfers. In Flow City, it is not the passenger who has to change trains anymore; instead it is the wagon – the bubble – of the train that moves separately and changes on behalf of the passenger. Via bypass connections crossings of different tracks are linked and differences of the track levels are resolved by a mass-independent system called Bubble Inertial Transportation System.

Flow City turns long and inconvenient transfers into a thing of the past.