CSF117 Module 3 IoT Sensors

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Welcome to the IoT sensors module. This module aims to facilitate learning of the different types of sensors and how they can be used in creating IoT solutions. We will look at analog sensors and digital sensors and how these can be interfaced with Arduino
Welcome to this module where we will learn about the different types of sensors that are used in IoT. It helps to have gone through the previous modules of IoT architecture and components as well as IoT protocol stack. Any computing system will have an input and an output. IoTs are no different. They too have inputs and outputs. The difference being that the inputs are from sensors such as temperature, humidity, sound and so on. Outputs for IoT are manifested by actuators such as motors, servos, segment displays, speakers and so on. In this module we will learn about sensors. The next module will cover actuators. Sensors are hardware components that collect data from the environment. They are part of the IoT ecosystem and bridge between the physical world and the digital world. They collect data about the environment such as temperature, humidity, pressure and so on. When sourcing for the type of sensor for your project, there are several considerations you need to make. The first one is the purpose of the component. For example, you may want to detect the temperature of a room. This would require a sensor that provides some signal based on the varying temperature. Another consideration is the range of values. Sensors will have an operating range and you will need to source for one that can work for you in your project’s environment. Another consideration is the accuracy and precision of the sensor. Depending on the project you are working on, it is important to get the right sensor. Additionally, you may want to choose between a digital sensor and an analogue one. Digital sensors tend to make it easier for you to read data, from a programming standpoint and also from the logistical perspective because some Arduino and other boards tend to have few analog input pins. Also, some analog sensors might require additional analog components such as resistors, capacitors, transistors and so on to regulate the signal enroute to your Arduino input pin. Sometimes, extra components may be required when using sensors, especially for analogue sensors. For example, it may be necessary to add components such as transistors, capacitors, resistors, voltage dividers or even MOSFETs. These analogue components may be used to prepare the signal for input to the microcontroller so that it is at the expected voltage range and power requirements for the input pins of your microcontroller. This means that before you plug in a sensor, it is important to know the operating voltage and current.