Reprogrammable 3D Shape-Changing Pneumatic Material for Programmable Matter

Programmable matter refers to matter that can change its physical properties in a programmable and controlled manner. This type of material can alter characteristics such as shape, density, moduli, conductivity, and optical properties based on external inputs or autonomous sensing. Many methods exist for programming shape change through heat, magnetic fields, piezoelectric materials, and inflation. However, shape changes through inflation face challenges such as complexity in achieving precise shapes, energy consumption, and load-bearing capacity. In this work, a 3D shape-changing interface that is pneumatically actuated and can be reprogrammed is proposed. The design of the material is carried out by developing different fabrication methods and analyzing its behavior based on durability, reproducibility, and shape control. The resulting material consists of a silicone rubber membrane containing a polycaprolactone (PCL) layer as a phase change material (PCM) that may be solid or melted. By selectively melting different regions of the PCM layer, the membrane inflation, and thus shape, can be programmed. The shape after actuation is held autonomously as the PCM solidifies and may be completely melted again to restore its initial configuration. This work demonstrates an interface with such capabilities for the first time and may serve as a foundation for developing more advanced systems.