Bearing Fault Monitoring Based on Flexible Piezoelectric Accelerometer

Bearings as indispensable parts of modern industry, play the key role in the rotating performance, quality, and reliability of mechanical equipment. It is necessary to develop attractive strategies to continuously monitor the status in real time to evaluate the lifetime performance of bearings. In this work, different from conventionally-utilized accelerometer fixed on the bearing housing, this work focuses on flexible piezoelectric accelerometers with low-frequency sensitivity and high voltage output. Through the by in-situ direct writing printing technique, the flexible piezoelectric accelerometers is fabricated by the piezoelectric polymer PVDF-TrFE coating on the substrate of a beryllium-copper cantilever beam. The performance of flexible accelerometer mounted on the bearing housing of the self-designed bearing testbench is evaluated by monitoring the failure of the inner and outer rings of the bearing. The measured time domain signals and spectrums indicate that the flexible accelerometer embodies excellent vibration monitoring capability and detection accuracy. This study preliminarily explored the feasibility of flexible piezoelectric polymer spraying technique in vibration monitoring and sensing.