Inflatable systems have been attracting attention in the field of interaction design. Conventional tabletop-sized pneumatic systems tend to be complex because they require bulky and noisy equipment. Therefore, several liquid-to-gas phase change actuators that use vaporization have been proposed. But these actuators have problems with controllability, reusability, and reconfigurability. In this study, we propose InflatableMod, novel inflatable modules based on the efficient control of liquid-to-gas phase change actuators. These are designed with a compact circuit that has a liquid transfer function to feed the required amount of low-boiling-point liquid into the pouch and a heating function to inflate the pouch by the volume change. This approach allows for a compact, silent, and untethered inflatable system. It is also possible to create an untethered and reconfigurable multi-inflatable system because each module is synchronized. In this paper, we propose the design of the modules, evaluate their performance, and present application scenarios.

In recent years, actuators that handle fluids such as gases and liquids have been attracting attention for their applications in soft robots and shape-changing interfaces. In the field of HCI, there have been various inflatable prototyping tools that utilize air control, however, very few tools for liquid control have been developed. In this study, we propose HydroMod, new constructive modules that can easily generate liquid flow and programmatically control liquid flow, with the aim of lowering the barrier to entry for prototyping with liquids. HydroMod consists of palm-sized small modules, which can generate liquid flow with the electrohydrodynamics (EHD) phenomenon by simply connecting the modules. Moreover, users can configure and control the flow path by simply recombining the modules. In this paper, we propose the design of the modules, evaluate the performance of HydroMod as a fluid system, and also show the possible application scenarios of fluid prototyping using this system.