Flexible Ultra-Low Power Strain Gauge Readout Platform for Sensor-Integrating Bolts

The monitoring of machine conditions and structural elements is crucial for predicting physical damage, avoiding downtime, and ensuring the reliability of critical infrastructure. sensor-integrating machine elements (SiMes) enable in-situ measurement of relevant parameters while maintaining compatibility with standard designs. However, the integration of sensors and electronic systems in these components is challenging due to strict spatial and structural constraints. This paper presents a compact, ultra-low power readout platform for sensor-integrating bolts, capable of multiaxial force and torque measurement. The platform utilizes a modular design, combining a flexible folded PCB for the measurement circuitry with rigid module for power supply and communication, optimizing the use of limited space. The modular approach allows evaluating application specific energy supply and communication protocols. The proposed strain gauge readout system minimizes the energy consumption per measurement and can compensate temperature dependent offset drift, making it a suitable solution for energy constrained applications in varying environmental conditions.