Embedded Capacitive Pressure Sensing for Electrically Assisted Microrolling

This paper presents the design, characterization, and experimental evaluation of a wireless capacitive pressure sensor embedded within a rotating workroll of a microrolling machine for monitoring the production of micrometer-scaled texture on thin metallic workpiece. The sensor converts the spatial and temporal variations of pressure across the interface between the roll and workpiece into capacitance values, thereby experimentally establishing a quantitative correlation between the online measurement and the geometric features being formed on the workpiece, in real time. Analytical and numerical models have been developed to guide the design of the sensor to maximize the capacitance output while satisfying the space constraint. A sensitivity matrix linking the measured capacitance with pressure distribution has been established through numerical analysis. Simulation and experiments confirmed the effectiveness of the embedded sensor in enabling intelligent microrolling.