Condition Monitoring

The left case describes how to use our MEMS vibration sensor to monitor the condition of motors, allowing for predictive maintenance. The MEMS vibration sensor attached to a motor is directly connected to either PL-R4 SENSOR, a microcontrollerintegrated Industrial Raspberry Pi or rPL-vibration, a wireless sensor box.

In this case, over 15,000 data sets sampled by rPL-vibration at a sampling interval of 50 microseconds, are wirelessly sent to a rPL-master. If the measurement frequency is set to five times per day, the expected the battery life is 3 to 5 years. When raw data is received by the PL-R4, it is immediately processed by open source software, like SciPy, which applies mathematical algorithms, such as FFT or envelope transformation.

After plotting and evaluating the results, the data files are then sent to an external server, usually a customer’s database. Without knowing the mechanical parameters of the motors, our algorithms can still accurately detect early defects by continuously comparing defective index values with initial vibration samples. Because our PL-R4 motor condition monitoring software is open source, customers can freely customize the GUI, detection algorithm, or add additional features such as machine learning.

A Measurement Innovation with MEMS chips

Widely used in mobile phones, home appliances, and cars, microelectromechanical systems (MEMS) have made sensors significantly smaller and more reasonably priced. While time-of-flight collision sensors for cars and gyroscopes to detect angles of phones are well known, emerging MEMS technologies included doppler sensors to accurately measure speed and gas sensors which detect specific toxic gases.

Both have uses in industrial applications. As both MEMS and microcontrollers are IC chips, these two are easily combined. For example, our new acceleration sensor with the latest 20kHz MEMS accelerometer can directly connect to a PL-R4 SENSOR without any convertors. Combining MEMS sensors, a micro-controller, and an Industrial Raspberry Pi results in a high-end, industrial, economic, IoT measurement system.

Latest MEMS Acceleration Sensors Monitor Motor Condition

Mobile phones already equip MEMS accelerometers, but commercial-grade MEMS accelerometers can only measure up to 10kHz and have a low signal-noise ratio. Thus, their performance is not sufficient to monitor motors or other rotating mechanisms. However, combining the latest 20kHz+ MEMS accelerometers with a unique filtering circuit, our MEMS acceleration sensor has achieved unprecedented standard of high-frequency sensitivity with very little noise. Despite costing less than US$300, it can detect abnormal high frequency noise caused by damaged bearings. By connecting this sensor directly to a microcontroller integrated with an Industrial Raspberry Pi, the rPL acceleration sensor box, or PL-vibration, can detect 20kHz sounds that last as short as 50 microseconds. We are always looking for new ways to increase our portfolio of MEMS sensor products. Please contact us if you have projects or ideas to develop industrial-grade, MEMS-based sensors.