We can ﬁnd sensors everywhere. Sensors are vital to our awareness of our surroundings and provide safety, security, and monitoring of the environment and health.
Among recent advances in sensor technology, smart sensors have been in the spotlight in their potential significance and wide range of application areas.
Ordinary sensors can be transformed into smart sensors, allowing them to perform complex calculations with collected data; thanks to the integration of computing and IoT in industrial processes.
Aside from increased capabilities, smart sensors have shrunk in size and flexibility, transforming bulky machines into high-tech intelligence. Smart sensors have evolved into devices with signal conditioning, embedded algorithms, and digital interfaces to detect and self-awareness.
What is a smart sensor?
A smart sensor combines a sensing element, an analog interface circuit, an analog to digital converter (ADC), and a communication interface in one housing.
The components of a smart sensor include sensors, power, communication, and signal processing typically provided by a microprocessor that can perform one or more functions, i.e., logic functions, two-way communication, and make decisions.
The five key components of a smart sensor are:
- The central unit or a microprocessor manages all the functions.
- Battery as the source of energy
- A transceiver interacts with the environment and collects data.
- Memory is used as storage media for storing data or processing data.
- Communication module that includes transceivers and forwards queries and data to and from the central module.
A smart sensor basically acquires physical, biological, or chemical input, converts the measured value into a digital format, and transmits the information via Ethernet to a computer monitoring point. In other words, the sensor signal is fed to the microprocessor, which processes the data and provides an informative output to an external user.
These sensors are designed as the Internet of Things components that convert real-time data into digital data sent to a gateway. Smart sensors can now predict and monitor real-time scenarios and take corrective action in real-time, thanks to these capabilities. Intelligent sensors perform complex multi-layered operations such as collecting raw data, adjusting sensitivity, and filtering, motion detection, analysis, and communication.
Wireless sensor networks (WSNs), for example, are smart sensor applications in which the nodes are connected to one or more other sensors and sensor hubs, forming a communication technology of some sort. Furthermore, data from multiple sensors can be combined to draw conclusions about an existing problem; for example, data from temperature and pressure sensors can be used to predict the onset of a mechanical failure.
A smart sensor possesses several functional layers starting from signal detection from discrete sensing elements, signal processing, data validation, and interpretation to signal transmission and display. Multiple sensors can be combined into a single, smart sensor system, with the microprocessor controlling operating properties such as bias voltage and temperature.
Types of smart sensors
- Acoustic: This type of smart sensors recognize audio vibration or frequency to determine activity, location, intensity
- Chemical: It measures fluid composition and concentration of biological/chemical compounds
- Electrical: It identifies and examines changes or disruptions in electrical or magnetic signals based upon environmental inputs or conditions
- Environmental: It monitors and assesses the deviations in physical state, conditions, or surroundings
- Image: It converts light waves into electrical signals to constitute a digital, optical form for visible condition monitoring
- Motion and force: These types of sensors measure static and dynamic objects to determine the type and rate of changes to their physical properties
- Touch: It detects body capacitance during physical contact between objects
Advantages of smart sensors
- Cost improvement – Reduce repair costs and maintenance downtime through better monitoring. Reduce the cost of bulk cables and connectors needed to connect different blocks (i.e., electronic circuits).
- Remote diagnostics, thanks to the processor within the package.
- Increase operational efficiency through automation. Perform real-time inventory tracking with improved demand planning.
- Enhancement of applications such as self-calibration, computation, communication and multi-sensing.
- System reliability is due to the reduction in system wiring and the ability to diagnose its own faults and effect.
- Better signal to noise ratio
- Non-linearity and cross-sensitivity