Misalignment Detection using a Wireless Sensor Mounted on a Rotating Shaft

Mechanical systems such as motors, pumps, engines, and turbine are all operation based on different shafts. Due to the heavily use of shafts, various faults such as cross-sectional cracks, looseness and misalignment may occur during their service life. In this study a novel approach is investigated to monitoring the shaft problems. The advancement in low cost and low power Micro Electro Mechanical Systems (MEMS) make it possible to develop an integrated a wireless sensor which can be mounted on the surface of rotating shafts to obtain vibration signals for condition monitoring. This measurement scheme can make the fault diagnosis of rotating shafts more effective because the signal to noise ratio is higher due to the direct sensor installation and combined response measurements. In this paper it focuses on using this sensing scheme to monitor shaft misalignment. Both theoretical analysis and experimental results shows that the scheme outperforms the Instantaneous Angular Speed (IAS) measurement in detecting shaft misalignments.