Application of low-cost MEMS accelerometer to measure unbalancing and load on a BLDC motor

The vibration analysis is widely used in industry as an efficient tool to monitoring equipments integrity and its structures. The vibration monitoring usually is a task which include large and expansive equipments. Recently, micro eletromechanical systems (MEMS) accelerometers devices has been used successfully in this purpose, having results each more times significant. The present work shows a low-cost MEMS accelerometer used to measure two variables in rotating machines: the unbalancing and mechanical load. Using the acceleration measurements in the three axis was possible to trace the FFTs characteristics of rotational movement of a BLDC motor for electric bike. With this measurements, it's possible to recognize when the machine is operating in anyone of this conditions and evaluate how much unbalancing or mechanical load are being applied.