At Sensors Expo 2018, Antonio Cirone from ST Microelectronics demonstrated and discussed different approaches for predictive maintenance for motors, fans and more using accelerometers, environmental and acoustic MEMS sensors.
The demo has two motors. The green motor is balanced properly and the red motor is out of balance. Spectrum analysis of the triaxial accelerometer output from the two motors shows the frequencies and the magnitude of the unbalance. However, temperature and humidity variations are also important.
The demo features the STEVAL-BFA001V1B, an industrial reference design kit designed for condition monitoring (CM) and predictive maintenance (PdM). Intended for monitoring motors, pumps and fans, the reference design can accelerate the development of predictive maintenance solutions for these applications.
Sensors in the reference design are:
- iNEMO 6DoF (ISM330DLC), an inertial measurement unit (IMU) using a 3D digital accelerometer and a 3D digital gyroscope
- Piezoresistive digital pressure sensor (LPS22HB) with a 260 to 1260 hPa absolute pressure range
- Capacitive digital relative humidity and temperature sensor (HTS221)
- Omnidirectional digital microphone sensor (MP34DT05-A)
The free firmware package (available on STSW-BFA001V1) includes dedicated algorithms for time and frequency domain signal processing and analysis of the 3D digital accelerometer with 3 kHz flat bandwidth. The reference design kit includes drivers for pressure, relative humidity and temperature sensor monitoring as well as algorithms for acoustic emission (AE) analysis.
Designed specifically for industrial usage, the layout (50mm x 9mm x 9mm) of the STEVAL-BFA001V1B meets IEC61000-4-2/4 and EN60947 requirements for industrial applications.