1. Overview
Accelerometers are motion sensors that measure acceleration forces (static or dynamic) along one or multiple axes. These devices convert mechanical motion into electrical signals, enabling quantitative analysis of vibration, tilt, shock, and dynamic movement. As core components in modern sensing systems, accelerometers play critical roles in consumer electronics, industrial automation, automotive safety systems, and aerospace navigation.
2. Main Types and Functional Classification
| Type | Functional Characteristics | Application Examples |
|---|
| Capacitive MEMS | High sensitivity, low power consumption, digital output | Smartphones, wearable devices |
| Piezoelectric | Self-powered, excellent frequency response | Vibration analysis, impact detection |
| Piezoresistive | High shock tolerance, analog output | Automotive crash testing, industrial monitoring |
| Servo (Force-Balance) | Ultra-high precision, low noise | Inertial navigation, seismic monitoring |
| Optical MEMS | Immune to electromagnetic interference | High-precision scientific instruments |
3. Structure and Components
Typical accelerometers consist of:
- Seismic mass with specific inertial properties
- Elastic suspension elements (springs or beams)
- Displacement detection circuit (capacitive, piezoelectric, or resistive)
- Temperature compensation circuitry
- Signal conditioning electronics
- Protective housing (metal/ceramic/polymer)
Modern MEMS devices integrate microstructures on silicon substrates with digital interfaces (I2C/SPI).
4. Key Technical Specifications
| Parameter | Description | Importance |
|---|
| Measurement Range | 2g to 500g | Determines application suitability |
| Resolution | 0.1mg to 10mg | Impacts measurement precision |
| Frequency Response | DC to 10kHz | Affects dynamic signal capture |
| Nonlinearity | 0.1% to 1% FS | Measurement accuracy indicator |
| Temperature Range | -40 C to +150 C | Environmental reliability |
| Power Consumption | 5 A to 10mA | Battery life consideration |
5. Application Fields
- Consumer Electronics: Smartphones (screen rotation), gaming controllers
- Automotive: Airbag deployment, electronic stability control (ESC)
- Industrial: Predictive maintenance systems, vibration monitoring
- Healthcare: Fall detection devices, rehabilitation equipment
- Aerospace: Flight control systems, structural health monitoring
- Case Study: iPhone's ADXL345 MEMS accelerometer enables step counting and orientation detection
6. Leading Manufacturers
| Manufacturer | Representative Product | Key Features |
|---|
| Analog Devices | ADXL345 | 3-axis, 13-bit resolution, I2C interface |
| STMicroelectronics | LSM6DSO | 6-axis IMU, AI-enabled edge computing |
| Bosch Sensortec | BMI270 | Low-power wearable sensor, 16Hz noise |
| TE Connectivity | KX134-1211 | 400g high-shock measurement |
| Honeywell | QA-750 | Tactical-grade servo accelerometer |
7. Selection Guidelines
- Determine required measurement axes (1D/2D/3D)
- Match range/sensitivity with application requirements
- Assess environmental conditions (temperature, vibration)
- Select appropriate output interface (analog/digital)
- Evaluate power consumption constraints
- Consider calibration requirements and long-term stability
8. Industry Trends
Key development directions include:
- MEMS technology advancement towards atomic-scale sensitivity
- Integration with gyroscopes and AI processing (smart sensors)
- Wireless sensor network compatibility
- Increased adoption in autonomous vehicles and IoT edge devices
- Development of ultra-low-power wake-up accelerometers
- Fiber optic accelerometer systems for aerospace applications
- Enhanced shock survivability for industrial harsh environments
