While urban computing has often been envisaged as bridging place, technology and people, there is a gap between the micro-level of urban computing which focuses on the solitary user with technological solutions and the macro-level which proposes grand visions of making better cities for the public. The gap is one of scale of audience as well as scale of normative ambition. To bridge this gap the paper proposes a transdisciplinary approach that brings together actor–network theory with critical and participatory design to create prototypes that engage people and build publics. The theoretical discussion examines a way of thinking about size as performative and shiftable through practical design methods. The micro/macro prototyping approach is demonstrated via an empirical case study of a series of provocative prototypes which attempt to build a material public around the issue of community noise at Heathrow airport. The paper suggests that this approach allows issues to be followed and engaged with, and their dynamics re-designed across different scales. This proposes a new role and scope for the researcher/designer as proactively engaging in normative shaping and supporting of real world settings which bridge place, technology and people. 
Micro/macro prototyping