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Sensor Technology Fundamentals and Applications: The Sensing Cornerstone of the Internet of Things
Posted in 知识科普 |Sensors, as the "sensory system" of Internet of Things (IoT), are the key technical basis for realizing the digitalization of the physical world. In this paper, we will systematically introduce the basic principles, main types of sensors and their typical applications in the field of IoT to help readers deeply understand the important position of sensor technology in the architecture of IoT.
I. Overview of sensor technology
1.1 Definition and Role of Sensors
Sensor (Sensor) is a detection device that can sense the measured information and can convert the detected information, according to a certain law, into electrical signals or other required forms of information output to meet the requirements of information transmission, processing, storage, display, recording and control. In the IoT architecture, sensors are located in the perception layer and undertake the important task of information acquisition.
1.2 Basic Sensor Characteristics
| Characteristic category | Specific parameters | clarification |
|---|---|---|
| Static properties | - Range - Accuracy - Resolution - Linearity | Indicators describing the performance of the sensor in steady state conditions |
| dynamic property | - Response Time - Stability - Lag | Describes the ability of the sensor to respond to changes in input |
Second, the main sensor type and principle
1.3 History of Sensors
The development of sensor technology has gone through a number of important stages, each of which has brought about significant technological breakthroughs and application innovations.
- First Generation (1950s-1970s): Mechanical sensors, mainly based on mechanical structures and simple electronic components
- Second generation (1970s-1990s): Electronic sensors with improved accuracy due to the use of integrated circuit technology
- Third generation (1990s-2010s):: Intelligent sensors, incorporating digital processing capabilities and communication functions
- New Generation (2010s-present): MEMS and nanosensors for miniaturization, intelligence and networking
Global Sensors Market Size Forecast (2020-2025)
| vintages | Market size ($ billion) | growth rate (esp. in economics) |
|---|---|---|
| 2020 | 1660 | – |
| 2021 | 1850 | 11.4% |
| 2022 | 2100 | 13.5% |
| 2023 | 2380 | 13.3% |
| 2024 | 2720 | 14.3% |
| 2025 | 3150 | 15.8% |
Second, the main sensor type and principle
2.1 Temperature Sensors
Temperature sensors are one of the most common types of sensors used in IoT applications, and their operating principle is based on the thermoelectric or resistive temperature properties of materials.
Main types and characteristics:
- thermocouples
- Principle of operation: Seebeck effect
- Advantage: Wide range (-200℃~2000℃)
- Application: Industrial process control
- thermistor
- Principle of operation: Semiconductor thermal effect
- Advantage: High sensitivity and low cost
- Application: Consumer Electronics
- infrared thermometry
- Working Principle: Blackbody Radiation Principle
- Advantage: non-contact measurement
- Applications: medical testing, industrial temperature measurement
2.2 Pressure sensors
Pressure sensors have a wide range of applications in industrial automation, automotive electronics and consumer electronics.
| typology | Working Principle | specificities | major application |
|---|---|---|---|
| resistive | piezoresistive effect | Simple structure and low cost | Industrial Pressure Measurement |
| capacitive | Capacitance change | High accuracy and low temperature drift | precision instruments |
| piezoelectric | piezoelectric effect | Fast response and large dynamic range | Dynamic pressure measurement |
III. Sensor applications in the Internet of Things
3.1 Smart Home Applications
Smart home is one of the most important application scenarios of IoT, in which all kinds of sensors play a key role.
Typical application scenarios:
- environmental monitoring - Temperature and Humidity Monitoring - Air Quality Detection - Light Intensity Sensor
- security system - Human Motion Detection - Door and Window Condition Monitoring - Smoke and fire alarm
- energy management - Electricity monitoring - Water and gas meter data collection - Solar system monitoring
IV. Sensor Selection and Application Design
4.1 Key Considerations for Sensor Selection
| dimension of consideration | Key indicators | Assessment points |
|---|---|---|
| Technical Parameters |
- Measurement range - Accuracy requirements - response time - resolution (of a photo) |
Determine technical specification requirements based on the specific needs of the application scenario |
| environmental adaptation |
- Operating Temperature Range - protection class - Anti-interference capability |
Consideration of the various influences of the actual application environment |
| economics |
- Acquisition costs - Maintenance costs - life expectancy |
Comprehensive assessment of total cost of ownership (TCO) |
4.2 Systems Integration Best Practices
Hardware integration points:
- Signal Conditioning Circuit Design
- Amplifier circuits
- filter circuit
- analog-to-digital conversion - power management
- Low Power Design
- Power Supply Ripple Suppression
- Electromagnetic compatibility considerations - Communication interface selection
- Analog output (0-5V, 4-20mA)
- Digital interface (I2C, SPI, RS485)
- Wireless Communications (WiFi, LoRa, NB-IoT)
4.3 Application case studies
Intelligent Factory Temperature Monitoring System
Below is a real-world industrial application example that demonstrates the use of temperature sensors in a smart factory.
System Composition:
- Sensor type: PT100 platinum resistance
- Measuring range: -50℃ ~ 200℃
- Accuracy requirement: ±0.5℃
- Sampling frequency: 10Hz
- Communication mode: RS485 bus
smart factory
Implementation effects:
- Equipment Failure Warning Accuracy Improved 40%
- Maintenance Cost Reduction 30%
- Product quality one time pass rate increase 15%
Content Reviewer: Josh Xu
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