Sensors form the edge of the electronics ecosystem, in which the physical world interacts with computers, thereby providing a rich array of data to be available at a click of a mouse. We have had sensors, actuators and RFID tags around for a couple of decades now which has made our lives easier to a great extent. From identification and tracking of objects while managing inventory to even the miniscule sensors present in our cell phones, gaming consoles and automobiles, Sensors have become quite ubiquitous.

With the “Internet of Things” era being ushered in, the potential of sensors have grown multi-fold. The Internet of Things (IoT) is the networked interconnection of objects through identifiers such as sensors, RFID tags and IP addresses. The Internet of Things aims to interconnect all things around us and ensure intelligence. There are several reasons why the IoT has become the flavor of the day; Internet Protocol Version 6 extended the number of unique Internet addresses making it possible for trillions of objects to connect to the net. This along with the ascent of cloud computing and the depreciating cost of sensors, have contributed to making the world a much connected and smaller place to live in.

Some of the standard sensors include movement (via accelerometer), sound, light, electric potential (via potentiometer), temperature, moisture, location (via GPS), heart rate, GSR (galvanic skin response/ conductivity) and more. These sensors are included in a variety of devices and solutions. The trend is moving towards multi-sensor platforms that incorporate several sensing elements.

Here is a look at how sensors are relevant in our day-to-day life:

Sensor and Medical Electronics:

Advanced development in sensors has enabled the design of miniature, cost effective smart medical devices. Medical professionals today require real-time, reliable and accurate diagnostic results which are provided by devices that are available either at hospitals or with patients at home being monitored remotely. There are developers constantly working towards incorporating sensors into the lives of patients which can capture both beneficial and detrimental health factors. Imagine physiological data being collected without your realization. Sensors embedded in the floor mat can measure your weight and gait; an arm patch can detect heart rate, blood pressure and blood sugar, while sensors in your toothbrush can detect cavities that would require attention or early signs of ulcer. Though these examples seem surreal, there are several of these sensor embedded devices already available in the market. The medical sensors in wearable devices are being used to build applications which can detect panic or medical emergency and which will notify friends, family or emergency services for help.

Approved in 2011, digestible sensor is another interesting development in healthcare. A digestible sensor is a sensor (similar to a pill) that transmits information about a patient to medical professionals to help them customize the care to the individual. Digestible sensors will monitor your bodily systems and wirelessly transmit what’s happening in your body to another device like your smartphone or computer for your own review or the review of your doctor. With the advent of IoT and related services, health records are getting networked and vital information can be made available to patients and his/her practitioner at any point of time and location. The various sensors that find application in healthcare include pressure, temperature, chemical flow, level, position and image and biosensors.

Sensors and Home Automation:

Smart buildings or homes are now the order of the day for those looking at convenience, security and a green environment. Networked homes automatically dim or turn off lights when people leave and adjust energy use based on physical presence. Such networked homes depend on a network of sensors to determine people’s usage of resources along with environmental factors like temperature, humidity and the time of the day.

One of the most popular use of sensor technologies is the motion detector. These sensors can sense when there are people entering or leaving the room. The benefits are two-fold – to switch lights on and off when entering or leaving a room or to trigger a burglar alarm when the house is empty. Light sensors or photo sensors as they are commonly called monitors ambient light levels and reports them back to the automation controller. These are used in conjunction with motion sensors to switch lights on automatically when someone enters a room. They can be also used to ensure few lights only operate after dark.

Temperature sensors are usually embedded into a thermostat unit or radiator actuator valve, but there are sensors that can be easily embedded into walls as well. Combined with a humidity sensor, these sensors can be used to automatically control air conditioners or de-humidifiers or even to control windows (automatically open or shut).

Sensors and Industrial Automation

Sensors play a very important role in the Industrial automation segment by making products or systems highly intelligent and automatic. This allows one to detect, analyze, measure and process various changes occurring in the system. These industrial sensors also play an important role in predicting and preventing future events.  Industrial sensor integration manufacturing automation include proximity sensor, vision sensors, ultrasonic sensors, position sensors, photoelectric sensors, temperature sensors, inclination sensors etc.

At the heart of industrial automation is a new generation of advanced intelligent sensors and motor drives which are connected through low-latency and real time networks to high performance performance programmable logic controllers (PLC) and Human-Machine Interface (HMI) systems. In order to be beneficial, sensors must be fast and reliable to be able to monitor or measure conditions in a fast paced industrial environment. The network should then be able to communicate this information with minimum latency and interruptions to ensure response in real time.

Sensors and Wearable Electronics:

A few years ago, it was difficult to integrate sensors with wearables because of the size of the sensors. With the advent of miniaturized, high-quality sensors, wearables can now be easily deployed for gathering physiological and movement data (gesture and voice recognition).

Most wearables use multiple sensors that are typically integrated into sensor networks. In the case of body-worn sensors for medical purposes, data can be gathered and uploaded to a remote site such as a hospital server. Sensors in wearables allow continuous physiological monitoring with reduced manual intervention and at a low cost. The explosion in Internet-connected sensors means that new classes of technical capability and application are being created.

Seeing how sensors have progressed in the last decade, it is exciting to think of the new sensing capabilities that will become widely available in the future.

*Published in EE Times India