Introduction to Home Automation

Editor's Notes

1. [SLIDE 1] Hello everybody! Are you excited to learn about Smart Homes? Let's start with a little video.
2. [SLIDE 3] Here's our agenda for today.
3. [SLIDE 4] A little about my experience with HA. I've been involved with HA for about 10 years. I'm using a whole bunch of different things that I can control remotely, from wall switches, to thermostats, to pet toys, you name it. I participate in DIY HA community by supporting new products, blogging, tweeting, contributing to Wikipedia, participating in HA contests (and occasionally winning some). I was crazy enough to get certified in several HA related fields.
4. [SLIDE 5] So, what is home automation? Here’s how Wikipedia defines it. I highlighted the two areas, that are most important, in my opinion. Those areas are “centralized control” and “automation of routine activities”. There's one other aspect that should be mentioned - awareness - informing or notifying users about what's happening in their home and aggregating that data, so that we could analyze it and use it to improve the efficiency of our life by automating certain tasks.
5. [SLIDE 6] For example... Imagine that you wake up every morning at 6am, go downstairs to turn on your coffee machine, then go back upstairs to take a shower. Turn on the TV or the radio to get update on the news. Then you leave for work. Now, wouldn't it be great if you could just wake up, push "Good morning" button and have the lights come up, TV turn on, coffee machine start brewing. And when you leave the house, have all those things just turn off automatically, so you wouldn't have to worry if you left something ON.
6. [SLIDE 7] Here's a list of a few things that are commonly found in automated homes. Some of those things could be simply plugged in to the outlets, others might require professional installation and setup. A separate category is the technology bridges that allow devices talking in different languages to communicate with each other.
7. [SLIDE 8] Here's how some of those smart products might look like. All these products are made by SmartLabs, company headquartered in Irvine, CA.
8. [SLIDE 9] Here's what a typical automated home blueprint looks like. You'd have some plugged in or wired in devices like lights or thermostats. Some sensors, which are usually battery powered. You would also have some control interfaces, like wall touch panels, or tablets. Or it could be a voice control interface like Amazon Echo. All those things would talk to an Internet-connected Hub, which would allow you to control your home from the outside and receive notifications to your mobile phone. Some systems would also have a cloud component that would be charged with processing events happening in your house and executing some actions or programs based on those events. A new trend in home automation are third party cloud services like IFTTT, that allow to bridge systems talking in different languages.
9. [SLIDE 10] Historically, every manufacturer was trying to differentiate its offering by designing their own communication protocol for their devices. And that was one of the reasons why it took so long for home automation to ramp up. Each protocol has its cons and pros. But fundamentally they all were designed as lightweight communication protocols for low-latency transmission of small data packets. In other words the protocol should be suitable for battery-operated devices. That's why WiFi in most cases is not the best choice when it comes to home automation - it's very power hungry. The granddaddy of home automation protocols - X10 - was developed in 1975 by Scottish company Pico Electronics. It's primarily a power-line protocol, meaning that the signal from one device travels to another through electrical wiring. Wireless X10 devices, such as key fobs and motion sensors use 310 MHz radio band. The problem with X10 is that it's very sensitive to interference in the power line. Some devices with motors and transformers, like vacuum cleaners, can absorb X10 signals. Message Queue Telemetry Transport (or MQTT) is a publish/subscribe messaging transport, using lightweight JSON payload. Since it doesn't have any built-in security, it's usually being used with TLS. ZigBee and Z-Wave are currently two most widely adopted protocols. Z-Wave uses proprietary radio whereas ZigBee is an international standard using 802.15.4 radio. Insteon is a dual-band mesh network, meaning that most devices send power-line and radio signals at the same time and each device functions as repeater. It's compatible with X10, but addresses most X10 issues, like speed of communication, acknowledgement of commands, number of devices supported on the network, etc. Bluetooth Smart could be found in most mobile phones, and devices like Apple's iBeacon. Thread is the most recent addition, currently used by Nest.
10. [SLIDE 11] How can we control all these devices? It could be either some specialized equipment (usually called hub) or a software application running on a regular computer or even on Raspberry Pi. Here's a list of some popular solutions. We are not got going to go into details of hardware components. As far as software goes, there are too many options available. Here are a few worth mentioning. HomeKit doesn't really fit into neither category. It's a hardware certification program. Apple requires strong encryption and a special chip for authentication. So, theoretically, existing products could not be updated for HomeKit. In practice, though, Apple allows that only hub to be HomeKit certified, not the devices. That was the case with Philips Hue and Insteon Pro. Google's answer to HomeKit is Project Brillo, which is a more comprehensive solution, that includes Android-based OS, core services and SDK for devices. It uses Weave as communication platform. Weave in turn could use Thread as device protocol. The other two apps are popular open-source projects.
11. [SLIDE 12] Cloud services allow to bridge different systems around your home. They could help with creating complex scenarios and communicate with remote services. You can use them to analyze the data created by sensors and use machine learning to give recommendations. For example, you know that Google Navigation analyzes traffic patterns and proposes alternative routes based on that data. Same principals apply to home automation. The service can analyze electricity usage in your home and suggest that you do your laundry, let's say, on Tuesdays between 2 and 5 pm.
12. [SLIDE 13] Here's a sample of IFTTT channels and the integrations they provide. For example, your NEST thermostat could make sure all lights are off when you leave the house. Or your BMW can open your garage door when you return home.
13. [SLIDE 14] As we all know in the past security was an afterthought in IoT, and home automation is no different. Most devices were not designed to be field upgradable. There are lots of devices on the market that were made 10-15 years ago with security issues that will never be fixed. Unfortunately, latest research shows that even secured communications could reveal sensitive data. For example by analyzing communication patterns, like frequency of communication, length of packets, etc, it's possible to determine if the user is currently at home or not.
14. [SLIDE 15] These are the key findings of a Symantec research where they tested 50 smart home devices from different systems. They found issues in all layers, from devices themselves, to mobile apps, to cloud services.
15. [SLIDE 16] Anybody want to see a demo?
16. [SLIDE 17] This is the kind of messages I get from my plants when they get thirsty. I'm using PlantLink system that has little sensors that you stick into the soil. They measure the moisture and based on the plant's type they tell me when each plant needs to be watered.
17. [SLIDE 18] Here we have a few Insteon devices, a lamp module, contact sensor and a remote control. They are linked between each other - without a central controller. If I press a button on the remote, it will send a radio command to the lamp module that will turn on this night light. TaDa! And this is a magnetic door sensor you might've seen in security systems. When the door is closed the two parts are close to each other. When you open the door they get separated and a radio command gets sent. So, I have a motion sensor outside of my front door, and whenever someone walks up the outside lights come on, the photo is taken by the camera and sent to my email. And when the door opens the lights in the foyer light up automatically.
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19. [SLIDE 20] Let's talk a bit more about the protocols used in home automation.
20. [SLIDE 21] Here's an overview of the protocols we've discussed. You can see similarities in radio frequencies they are using - either 900 MHz or 2.4 GHz. These frequencies do not require licensing (but require FCC/CE certification). Most use some sort of routed mesh networking. Most require a Hub or a central controller.
21. [SLIDE 22] Here you can see a few popular systems, the kind of devices, protocols and mobile platforms they support. Most systems also provide APIs that allow to extend its functionality.
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