IoT refers to the connection of all objects, whether big and small, static or mobile, to the Internet and all the services available there. If you've been in the industry for some time, you'll recognize this as an evolution of embedded and distributed M2M systems that have been building over the course of many years. Now, since we have talked much about the Internet of Things (IoT) let’s talk about one of the components that makes it throb, the sensors. If everything is connected to everything and still we don’t know what is happening, then what good is it to have? This is precisely where sensors come into play.
A sensor is a sophisticated device that measures a physical quantity like speed/pressure and converts it into a signal that can be measured electrically. Sensors are based on several working principals and kinds of measurements. You will not only be surprised to know how many sensor types exist, but also how many exist within each sub-category. Choosing the right sensor based on your power, space, cost, ergonomics, etc. may not make or break your solution, but surely make a difference to how it operates.
Let’s see a case where we are looking for sensors to fit in object tracking. The aim is to track a target placed in front of a device. There are many IoT sensors that can be used for a simple application like line following (IR LED and a Photodiode, LED and LDR, etc.), but this is a simple case where a simple sensor can be selected. We can also go for ultrasonic sensor to scan from side to side, till the sensor detects a drop in distance. This is one of the cases where expensive products can be replaced with cheaper sensors.
Selecting the right IoT sensor is not a strict process. This is about eliminating all the wrong choices.
In other words, the sensor has to be selected in concordance with your target’s size, shape, and range. When we say the word “target”, we refer at the same time, a small ball, an object like a chair, or even a human being in front of the device. All of these three features have to be on the same line with the specification of the device to be designed. But even so, it is hard to define the best sensor since the performance and precision of this depends on many factors.
In the next article, we will explore the features of IoT sensors that can be used for object or obstacle detection.