What are IoT sensors?
A sensor is a physical device or biological organ that can detect and collect information about the surrounding environment and transmit the detected information to other devices or organs. These sensor devices can be electrical, mechanical, magnetic, electromechanical, electromagnetic, optical, or chemical, etc. Sensors are placed at the location of use or near a network, and come in various sizes depending on the application. They can be individual components or integrated into other products, such as installed inside engines, smart thermostats, smartwatches, or smartphones. The data collected by sensors is sent back to a central network for storage and processing.
Fruit diameter sensor Fruit diameter sensor
What data do sensors collect?
IoT sensors can collect any data that can be observed or measured. Here is a partial list:
● Temperature and heat
● Pressure
● Moisture
● Motion
● Vibration
● Chemical/Smoke/Gas
● Optical information, such as infrared and visible light
● Fluid information, such as gases, liquids, and slurries
● Sound and acoustics
● Visual information (cameras, patterns, etc.)
● Current/Electricity
● Position
● Speed
Antenna and sensor node layout for detecting flood levels
Considerations for installing IoT sensors
When planning and implementing an IoT project, consider the following:
What is the application? Depending on the purpose, sensors can be installed in a confined space (e.g., inside a room or building) or at relatively distant locations (e.g., at a construction site). The specific use determines the type of sensors, what data needs to be collected, how data is sent, and sensor placement.
What data needs to be collected? For mission-critical or time-sensitive data, sensitive location data, or geospatial-related data, higher precision sensors are required. Determine, based on the specific application, what secondary data needs to be collected in addition to the primary data, and clarify the accuracy of the collected data.
How often is data collected? Data can be collected continuously at preset intervals, triggered by events, or collected as needed. In continuous manufacturing applications, such as chemical processes, sensors need to record data continuously, but not all applications require such frequent data collection.
In what environment will the sensors operate? Sensors operating in harsh environments (pressure, temperature, vibration, radiation, etc.) need protection to ensure their stability and sustainability.
How much data will be collected? Some sensors collect only a few bytes of data, while others (such as cameras) collect megabytes of data. The more data collected, the greater the storage capacity and the higher the requirements for data transmission.
How often is data transmitted back to the central network? Applications with mission-critical or time-sensitive data need to send data immediately after collection for processing. Other applications, such as autonomous vehicles, need to transmit sensor data to a local computer center for processing, rather than to a central network. From an energy perspective, the higher the frequency of data transmission, the more power it consumes.
How is data transmitted back to the network center? Data collected by sensors can be transmitted via cables or wirelessly. The specific application will determine the transmission method.
How are sensors powered? IoT sensors can be powered by batteries, solar energy, or cables. Sensors installed in remote or hard-to-reach locations can be powered by batteries or solar energy. However, replacing batteries for thousands of sensors in remote areas is a difficult and impractical task. In such applications, sensors should be low-power and efficient to extend battery life. The higher the data transmission frequency and the larger the data volume, the more power is consumed. In this case, the power technology and energy supply method of the sensors need to be considered.
What are the security requirements? Sensitive or confidential data needs to be encrypted before transmission, and sensors need to be authenticated before data is processed at the central network.
What are the data format requirements? Different applications have different data formats. When data is sent back to the central network, the platform must be able to integrate all data of different formats.
What is the total cost? The total cost includes the cost of purchasing sensors, as well as all costs incurred during installation, integration, operation, maintenance, replacement, and eventual decommissioning. Compared to a sensor network built with many cheap sensors deployed over a large area, a small sensor network using a few expensive sensors locally may have lower costs.
What specific technology is required for installing IoT sensors? Some sensors are part of the IoT ecosystem and are easy to configure, requiring limited programming to deploy. Others may require specialized programming and integration to use.
