Making anything “Smart”

• Very little of this smart home stuff is really “necessary”
• For me it’s a game of “can I make this work?”
• Like putting together a puzzle or solving a riddle
• What are the Principles and Tools I use when tackling a smart home puzzle?

Principles of the Tinkerer:

• Willingness to figure stuff out
  • If I waited until I understood something completely before attempting it, I would rarely accomplish anything
  • Asking an “expert” is fine, but figuring it out by experimenting and failing should always be part of the process
• Be prepared to break it
  • To make the best kinds of discoveries I have to be prepared to take things apart and poke around inside to see how they work
  • That means you might break it in the process of figuring out how it works
  • Maybe it’s not a great idea to tinker around with very expensive or difficult to replace equipment
  • Same goes for items that are critical for safety.  It’s fine to take apart a lamp, or a vacuum, or the coffee maker, but not the smoke detector.
• Document your disassembly
  • “Don’t lose the screws”
  • We all have easy access to a digital camera with our phones.  Take lots of pictures as you take things apart so you’ll have a record when it comes time to put it back together

Tools of the Tinkerer:

• Basic understanding of Electricity
  • If you don’t know the difference between a Volt and an Amp you probably shouldn’t be poking around inside anything electrical.
  • Fortunately there are many good resources for learning the basics of electricity.
  • I’m a Physician.  I have taken many many classes on all kinds of topics. My favorite textbook is still “Basics of Electricity”.  I keep it by my workbench even to this day.
  • Electricity is based on Magnetism, and Magnetism is Magic.  That means having an understanding of Electricity and being able to manipulate Magnetism and Electricity makes us modern day Wizards.
  • So find a good source and get a solid functional understanding of Electricity
• Get a Mulit-meter
  • I use my cheap $12 multimeter almost every day.
  • Continuity is the most important function.  It tells you when one end of a wire, or a contact point is electrically connected to another.  For example, I use it to find which solder point on a circuit board is connected to the on/off switch.
  • AC voltage detector is also super important.  Before tinkering around with electrical wiring in your house, use the AC detector to make sure the power is off to the wires you’ll be working on. Sometimes there are wires from two different circuit breakers in the same junction box.  Just turning off the breaker to the lights you’re working on doesn’t guarantee that all the wires in the box are safe to touch.
  • DC voltage detector is very useful for troubleshooting. If some electronic device isn’t working, I poke around looking for DC voltage.  If I can’t detect voltage where I think it should be that’s a good clue about which component might be causing the problem.
• Soldering Iron
  • This intimidates a lot of people.  Being able to solder (or unsolder) will take your electronics tinkering to the next level.
  • My tips for soldering:
    • Magnification
    • Thin gauge solder
    • Helping Hands to hold parts in place
    • Hold the iron still, move the solder wire
• Benchtop Power Supply
  • It’s very handy to have an adjustable source of power
  • Also shows the current when the device is running
  • With most multimeters you can get current readings too, but it’s not as convenient as just having it built in to the power supply

Making Dumb things Smart:

So you’ve disassembled your coffee maker, and you can see how it works, now what? Now you have to put together some electronics magic.  What Spells do electronics Wizards use?

• ESP microcontroller
  • The ESP8266 has been the main micro controller in just about every smart home product for > 5yrs.
  • It’s cheap, wifi, and there are plenty of ways to program it
  • ESP32 is the newer more powerful version
  • If you want to DIY some smart devices you absolutely must become familiar with the ESP microcontrollers
• Firmware
  • This is how you control the ESP microcontroller. There are many DIY firmware options available
  • Tasmota is my #1 recommendation
  • Simple user interface, lots of documentation, lots of development, lots of users to help
  • At this point there isn’t much Tasmota can’t do
• GPIO pins
  • General Purpose Input/Output
  • These can serve to sense or send low voltage signals
  • ESP8266 has 11 usable GPIO pins
  • ESP32 has 36
• Relay
  • The secret weapon for making any dumb thing smart
  • The simplest magic is to replace the mechanical “dumb” on/off switch with a relay
• Button or Switch
  • This can be any input device that gives an on/off, yes/no, 1/0 type of signal
  • Things like:
    • Physical buttons
    • End-stop switches
    • Motion detectors
    • Magnetic “Reed” switches (usually door/window sensors)
    • Any point in a device where some contact point goes from having a little voltage to having 0 voltage or being grounded

Summary:

• Don’t be limited by what smart devices are available off the shelf
• Be willing to tinker, poke around and figure things out
• Understanding Basics of Electricity makes you a modern day Wizard

Learn to use the ESP microcontroller, Relays and Buttons, and you can do just about anything