Machine Health Monitoring Using a Novel Low Cost Elastomer Based Vibration Sensor

This paper reports the application of an inexpensive polyurethane (PU) foam based vibration sensor for monitoring the state of operation of a 3-phase induction motor. Benchmarking the PU foam sensor data with a commercially available MEMS accelerometer ADXL335 suggests that the location of placement of the sensors on the machine has a strong effect on their relative sensitivity. While the PU foam sensor has less bandwidth (~80Hz) than the ADXL335 (>500Hz), it is more sensitive to sub-harmonics of the motor vibrations (that indicate loose housing) while also showing measurable response at higher harmonics of the vibration (that indicate misalignments).