Thin Shell Buckling enabling Fluidic Sensing

Due to their inherent compliance, soft fluidic robots can demonstrate the exceptional property of intrinsic sensing. This property enables the detection of environmental stimuli by monitoring the pressure of the robot's internal fluid cavity without requiring any embedded electronic components. Here, we look to leverage this intrinsic sensing capability in soft, thin shells to detect properties of unknown fluids. By placing a free, thin hemispherical shell against an unknown fluid basin, we aim to identify the fluidic characteristics by deflating the shell and investigating its buckling behavior. We use analytical methods to explore how the presence of the fluid alters the thin shell buckling problem of the hemisphere. Then, we discuss experimental and numerical techniques that show how monitoring the pressure-volume trend of the pneumatic cavity yields insights into the properties of the unknown fluid. This sensing methodology creates new opportunities for applications like hazardous fluid identification or low visibility sensing in fields like autonomous or surgical robotics.