Imaginaries, the fruit of discussions in the context of collaboration between researchers and professionals, can manifest in various material forms. In this contribution, our aim is to examine the imaginaries surrounding so-called ‘open’ technical innovation and its material forms through the case study of an ANR MeetUX Labcom collective. Our intention is to understand how the process of designing an integrative digital platform for “innovation through user experience” methods, envisaged as part of this project, contributes to the construction of a common ground, and how this process crystallises the collective’s imaginations of technical innovation. We will look specifically at the three issues that characterise the collective imagination of innovation: the importance of co-designing the innovation with all the stakeholders; the attention that needs to be paid to the place and role of emotions; and the choice of a platform as the goal of cooperation for a collective.