As young children’s screen time has significantly increased in recent years, their healthy use of digital media is a topic of interest. To support children’s healthy screen use, we are developing Romi, a physical screen peripheral device interface. Romi was designed to help children to transition from screen to out-of-screen by reducing negative experiences when ending screen time. To specify the design concept, we conducted the preliminary interview and experience prototyping focusing on screen-time transition. Based on design attributes which are the peripheral presence, the connection between screen and device, and friendly character, we implemented Romi interface. We believe our approach will provide motivation and inspiration for designing a physical interface for supporting children’s self-regulation.

In this paper, we present a metamaterial structure called thermoformable cells, TF-Cells, to enrich thermoforming for post-print modification. So far, thermoforming is limitedly applied for modifying a 3D printed object due to its low thermal conductivity. TF-Cells consists of beam arrays that affluently pass hot air and have high heat transference. Through heating the embedded TF-Cells of the printed object, users can modify not only the deeper area of the object surface but also its form factor. With a series of technical experiments, we investigated TF-Cells’ thermoformability, depending on their structure’s parameters, orientations, and heating conditions. Next, we present a series of compound cells consisting of TF-Cells and solid structure to adjust stiffness or reduce undesirable shape deformation. Adapting the results from the experiments, we built a simple tool for embedding TF-Cells into a 3D model. Using the tool, we implemented examples under contexts of mechanical fitting, ergonomic fitting, and aesthetic tuning.