Enterprise Internet of Things Handbook

Sensors

Sensors and actuators are the backbones of IoT. These are the entities that bridge the gap between the real world and the virtual world. In this section, we are going to look at sensors and in the next section, we are going to look at actuators.

Sensors are devices that can measure a particular property of nature. To simplify things, take a temperature sensor. A temperature sensor generally uses a thermistor. A thermistor is an electronic component whose resistance changes with changes in temperature.

In most thermistors, the resistance decreases as the temperature increases. These are called Negative Temperature Coefficient (NTC) thermistors.

Now, this resistance can either be converted to voltage and be read by a microcontroller ...