A fully self-powered hybrid system based on CMOS ICs and large-area electronics for large-scale strain monitoring

Large-area electronics (LAE) enables diverse transducers on large, flexible substrates (~10m
²
), making possible expansive sensor arrays and energy harvesting devices. We present a second-generation system for high-resolution structural-health monitoring of bridges achieved by combining LAE with CMOS ICs in a scalable architecture. It aims to enable strain sensing scalable down to cm-resolution over the large-area sheets. Compared to previous work [1], the system presents several advances, including self-powered operation with embedded energy harvesting, generalized readout and control interfaces for sensor arrays based on thin-film transistors (TFTs), and full integration of instrumentation and communication circuits for multi-sensor acquisition, digitization, and self calibration. The instrumentation subsystem achieves multi-channel strain sensing with sensitivity of 23μStrain
_RMS
, at an energy/measurement of 148nJ and 286nJ for readout and sensor-access control, respectively. The power-management subsystem achieves 30% efficiency for power inversion and inductive power delivery using a thin-film harvesting circuit with a solar module, and 80.5% overall efficiency for generating three voltage supplies via CMOS DC-DC converters.