Accelerometers

An accelerometer is a device that converts mechanical vibration or motion into an electrical signal. It measures acceleration (unit: g) by detecting the displacement change of a mass under acceleration. Its core principle is based on Newton’s second law. It can be categorized into piezoelectric, capacitive, and thermal convection types, with MEMS (micro-electromechanical systems) technology becoming the mainstream solution.

 

1. What are the Main Types of Accelerometers?

1) Piezoelectric Accelerometers

Utilize the piezoelectric effect of piezoelectric materials, which are suitable for high-frequency vibration monitoring (such as in aerospace).

 

Features: Wideband response and high natural frequency, but require an external power supply.

 

2) Capacitive MEMS Accelerometers

Measurement is achieved by detecting the change in the gap between capacitor plates and is widely used in consumer electronics (such as mobile phone pedometers).

 

Advantages: Low power consumption, high integration, and resolution up to μg levels.

 

3) Thermal Convection Sensors

Based on the principle of gas convection, they offer strong shock resistance and are suitable for automotive airbag deployment systems.

 

2. What are the Typical Applications of Accelerometers?

Industry 4.0: Equipment health monitoring (vibration analysis, predictive maintenance);

Autonomous Driving: Vehicle posture control, collision detection;

Medical Electronics: Wearable device activity tracking, respiratory monitoring;

Internet of Things: Smart home tipping alarms, structural health monitoring.

 

3. Key Selection Parameters of Accelerometers

Parameter	Description	Typical Range
Range	Maximum measurable acceleration	±2g to ±500g
Sensitivity	Output signal/acceleration	10mV/g to 1000mV/g
Bandwidth	Effective frequency range	DC-10kHz
Noise Density	Determines minimum measurable acceleration	10μg/√Hz to 100μg/√Hz