Sensor

SENSOR

     A sensor is a device that detects and responds to some type of input from the physical environment. The specific input could be light, heat, motion, moisture, pressure, or any one of a great number of other environmental phenomena. The output is generally a signal that is converted to human-readable display at the sensor location or transmitted electronically over a network for reading or further processing. 

Different Types of Sensors in Electronics

In our day-to-day life we got used to use different types of sensors frequently in our power systems such as electrical and electronics appliances, load control systems, home automation or industrial automation, and so on.

All types of sensors can be basically classified into analog sensors and digital sensors. But, there are a few types of sensors such as temperature sensors, IR sensors, ultrasonic sensors, pressure sensors, proximity sensors, and touch sensors are frequently used in most of the electronics applications.

• Temperature Sensor
• IR Sensor
• Ultrasonic Sensor
• Touch Sensor
• Proximity Sensors
• Pressure Sensor
• Level Sensors
• Smoke and Gas Sensors

Analog Sensors

There are different types of sensors that produce continuous analog output signal and these sensors are considered as analog sensors. This continuous output signal produced by the analog sensors is proportional to the measurand. There are various types of analog sensors; practical examples of various types of analog sensors are as follows: accelerometers, pressure sensors, light sensors, sound sensors, temperature sensors, and so on.

Digital Sensors

Electronic sensors or electrochemical sensors in which data conversion and data transmission takes place digitally are called as digital sensors. These digital sensors are replacing analog sensors as they are capable of overcoming the drawbacks of analog sensors. The digital sensor consists of majorly three components: senor, cable, and transmitter. In digital sensors, the signal measured is directly converted into digital signal output inside the digital sensor itself. And this digital signal is transmitted through cable digitally. There are different types of digital sensors that overcome disadvantages of analog sensors.

The future of sensor technology

• Sniffing out the 'smell of fear'

Professor Sun explains:

"Today there is an array of sensors being used at airports, ferry terminals and big events such as sports matches. We're all familiar with X-ray machines and metal detectors and you could even class sniffer dogs as a form of sensor. Our work, however, is designed to offer a better, more cost-effective and portable solution."

The projects, which are also supported by the Home Office Scientific Development Branch, have two key objectives. Firstly, to see whether robotic noses could replace sniffer dogs to track down illegal cargos such as explosives or drugs. Using animals in this context has several drawbacks - they must work in short shifts and require expensive training and upkeep - so an automated system would be welcome. A second aim is to assess the feasibility of using novel smell sensors to detect the 'fear' pheromone - a key physiological indicator that could be correlated with abnormal human behaviour.

• Managing concrete corrosion
• Keeping railways on track: The latest application for these innovative sensors is pantographs - overhead power lines - for railways.

Applications

• Pressure Sensors

• Piezoelectric transducer

• Humidity Sensor
• Gas Sensor: