The basis of ifm’s vibration products is a Micro-Electro-Mechanical System (MEMS) accelerometer integrated onto an IC chip that powers the sensor. MEMS technology uses nano-sized (10-9) mechanical components with nearly no mass or movement. The image below shows the relative gap distance between components. As these gaps change with vibration, the capacitance of the MEMS chip changes in direct proportion to the vibration.
Advantages of MEMS technology:
Disadvantages of MEMS technology
Piezoelectric elements accumulate electrical charges in response to mechanical stress, such as vibration. The amount of accumulated charges is proportional to the level of vibration.
Piezoelectric accelerometers consist of a seismic mass attached to a piezo material (like ceramic). When the accelerometer is subjected to vibration, a force is generated and a small millivolt change is measured. This voltage is proportional to the acceleration of the mass.
Advantages of piezo technology:
Disadvantages of piezo technology