It is almost impossible to classify sensors. It is a too broad concept and daily new sensor types and applications are arising. Some authors classify them one way and others in a complete different way. As an example sensors could be classified as passive or active, or by construction as MEMS or by principle as piezoelectric or capacitive or by what they measure/sense as optical or ultrasonic, etc. Every type could be sub divided into more specific categories and so on.
Anyway, sensors are used to measure basic physical phenomena including, but not limited to:
- Acceleration - Shock & Vibration
- Angular / Linear Position
- Chemical/Gas Concentration
- Humidity
- Flow Rate
- Force
- Magnetic Fields
- Pressure
- Proximity - Spatial Presence
- Sound
- Temperature
- Velocity
- Radiation and high energy particles
- Biologic / Biometric
- Optical & Infrared Sensors