This tutorial introduces the application of IoT in Home automation.
Home automation has three major parts :
- Communication protocols
Each of these parts is equally important in building a truly smart home experience for your customers. The important consideration is the firmware that resides in your hardware managing your data, managing data transfer, firmware OTA updates, and performing other critical operations to make things talk.
Some of the areas where consumers can expect to see home automation-led IoT-enabled connectivity are:
- Lighting control
- Lawn/Gardening management
- Smart Home Appliances
- Improved Home safety and security
- Home air quality and water quality monitoring
- Natural Language-based voice assistants
- Better Infotainment delivery
- Al-driven digital experiences
- Smart Switches
- Smart Locks
- Smart Energy Meters
Home Automation Components
The major components are as follows:
- IoT sensors
- IoT gateways
- IoT protocols
- IoT firmware
- IoT cloud and databases
- IoT middleware (if required)
IoT sensors involved in home automation are in thousands, and there are hundreds of home automation gateways as well. Most of the firmware is either written in C, Python, Node.js, or any other programming language.
Home Automation Sensors
- Temperature sensors
- Lux sensors
- Water level sensors
- Air composition sensors
- Video cameras for surveillance
- Voice/Sound sensors
- Pressure sensors
- Humidity sensors
- Infrared sensors
- Vibrations sensors
- Ultrasonic sensors
We can use one or many of these sensors depending on our need.
The famous temperature sensors are DHT11/22, DS18B20, LM35, and MSP430 scries from TI. The MSP430 series is more accurate than the rest, but at the same time, it is one of the most expensive for prototyping or initial product testing purposes. MSP430 tops all temperature sensors, as the precision and battery consumption is minimal with them.
The DHT11 has a very restricted temperature range and suffers from accuracy issues. DHT22, on the other hand, is a little bit more accurate but still, doesn’t make it the preference.
Lux sensors measure luminosity and can be used to trigger various functions ranging from cross-validating movements to turning the lights on if it becomes too dark. Some of the most popular light sensors are TSL2591 and BH1750.
Water Level Sensors
While building the prototype, we may consider a solid-state eTape liquid level sensor or, like others, just use an HC-SR04 ultrasonic sensor to measure the water level. Float level sensors and other ICs like LM1830 offer a more precise measurement capability to IoT developers – although, they are substantially much more expensive than others
Air Composition Sensors
There are many specific sensors that are used by developers to measure specific components in the air:
(i) CO monitoring by MiCS-5525
(i) MQ-8 to measure Hydrogen gas levels
(iii) MICS-2714 to measure nitrogen oxide
(iv) MQ135 to sense hazardous gas levels (NH3, NOx, Alcohol, Benzene, smoke CO2).
Most of these sensors have a heating time, which also means that they require a certain time before they actually start delivering accurate values.
These sensors mainly rely on their surface to detect gas components. When they initially start sensing, there’s always something that’s there on their surface, some sort of deposition that requires some heating to go away.
Video Cameras for Surveillance and Analytics
A range of webcams and cameras specific to hardware development kits are usually used in such scenarios. Hardware with USB ports offers to integrate camera modules to build functionality.
For eg., Raspberry Pi Ras comes with a camera module (Pi cam) that connects using a flex connector directly to the board without using the USB port. This makes the cam extremely efficient.
Sound detection is very essential for monitoring babies from automatically turning lights on and off to automatically detecting your dog’s sound at the door and opening it up for your pet. Some commonly used sensors for sound detection include the SEN-12462 and EasyVR Shield for rapid prototyping.
These sensors bring the capability of sensing humidity/RH levels in the air to smart homes. The accuracy and sensing precision depends a lot on multiple factors, including the overall sensor design and placement. But certain sensors like the DHT22 and 11, built for rapid prototyping, will always perform poorly when compared to high-quality sensors like HIH6100 and Dig RH.
Home Automation Protocols
For Building the home automation, the protocol that the device will use to communicate to gateways, servers, and sensors.
- Bluetooth Low Energy or Bluetooth Smart: Wireless protocol with mesh capabilities, security, data encryption algorithms, and much more. Ideal for IoT-based products for smart homes.
- Zigbee: Low-cost, mesh networked, and low-power radio frequency-based protocol for IoT. Different Zigbee versions don’t talk to each other.
- X10: A legacy protocol that utilizes powerline wiring for signaling and control.
- Insteon: Communicates with devices both wirelessly and with wires.
- Z-wave: Specializes in home automation with an emphasis on security.
Home Automation Gateways
For developing a home automation product, often a standalone product sending data to a server is not enough. Due to battery and protocol limitations, the data from a sensor or sensors present in a home has been routed through an IoT gateway.
To select the perfect gateway for IoT home automation, some of the factors are as follows:
- Communication protocols supported
- Real-time capabilities
- MQTT, COAP, and HTTPS support
- Security and configuration
Home Automation Frameworks
The architecture makes control and information flow possible. Home control consists of five components:
- State machine
- Event bus
- Service registry
The core architecture of Home Assistant:
All of these components working together create a seamless asynchronous system for smart home IoT. The best part about the home assistant’s core architecture is how carefully it has been designed and developed to support IoT at home.
OpenHAB is a home automation and IoT gateway framework for smart homes. Similar to Home Assistant, OpenHAB works nicely with Raspberry Pi and comes with its own design tools to create a UI for your home automation product.
The Architecture of OpenHAB
- Modularity: It is realized with the bundle concept
- Runtime dynamics: So that software components can be managed at runtime
- Service orientation: There are services for various components to speak with each other and exchange information
The following layer stack is
- Modular layer: Manages dependencies between bundles
- Life cycle layer: Controls the life cycle of the bundles
- Service layers: Defines a dynamic model of communication between various modules
- Actual services: This is the application layer, using all other layers
- Security layer: Optional, leverages Java 2 security architecture and manages permissions from different modules
Home Automation Smart Lighting
Smart lighting achieves energy savings by sensing human movements and their environments and controlling the lights accordingly. Wireless-enabled and Internet-connected lights can be controlled remotely from IoT applications such as mobile or web applications.
Home Automation Smart Appliances
Smart appliances make management easier and provide status information of appliances to the users remotely. E.g: a smart washer/dryer that can be controlled remotely and notified when the washing/drying cycle is complete. Open Remote is an open-source automation platform for smart homes and buildings that can control various appliances using mobile and web applications. It consists of three components:
(1) a Controller – that manages scheduling and runtime integration between devices.
(2) a Designer– allows for to creation of both configurations for the controller and user interface designs.
(3) Control Panel – allows to interact with devices and control them.
Home Automation Intrusion Detection
Home intrusion detection systems use security cameras and sensors to detect intrusions and raise alerts, The form of alerts can be in the form: of Email and a short video clip as an email attachment.
Home Automation Smoke/ Gas Detectors
Smoke detectors are installed in homes and buildings to detect smoke which is typically an early sign of fire. It uses optical detection, ionization, or air sampling techniques to detect Smoke The form of the alert can be the form: of signals that send to a fire alarm system a Gas detector can detect the presence of harmful gases such as carbon monoxide (CO), liquid petroleum gas (LPG), etc.
Read other IoT Tutorials