Real-time monitoring of pressure distribution in microrolling through embedded capacitive sensing

The temporal and spatial distributions of pressure across the roll-workpiece interface during the micro- form-rolling process are critical indicators for the quality of the formed textures. This paper presents a novel method for monitoring the pressure distribution through a set of capacitive sensors embedded within the roll. Numerical and analytical models of the sensor-embedded roll have been established for determining the optimal sensor dimension to maximize the capacitance output in the pico-Farad range, under space constraint. A transfer function of the sensor is established for retrieving the pressure distribution. The technique is evaluated by simulation and confirmed through experiments.