If you haven’t heard #MarchIsForMakers. As an initiative to get more tech savvy people interested in hardware, several tech organizations are promoting projects for tinkerers. For coders, writing programs requires us to have knowledge of how computer servers work to compile code. This March, we’re encouraged to get our hands dirty literally and make a programmable device in order to learn in the process. To celebrate, my latest series will focus on wearables, with the first post offering an introduction. Let’s get started!
What’s the Big Deal?
Google Glass, Fitbit wristbands, Apple Watches– they all fall into the category of wearable technology. Wearables are computer and electronic based tech that can be worn by a user, and includes basic functions, features, or fashion. Wearables can be networked to store data or send alerts to the user depending on the maker’s interest. Much of the tech used to create wearables are not new, but with the trend of the quantified self gaining popularity, the data gathered from wearables allows users to gain greater insight of themselves. Sensors used in the design can do tasks such as track sleeping patterns, count calories burned, measure heart rate, luminate surroundings, and even provide aid in hearing. Following along the internet of things trend, wearables are fashion with a focus: providing info users want and need on demand.
For those interested in building their own wearable device, there are materials that you’ll need to get started. Here’s a look at what your toolbox should include:
The Microcontroller: This is a small, programmable computer. Some are even washable. Examples include Arduino, Raspberry Pi, Launchpad, Penguino, Teensy and others. My writeup on different types of wearable microcontrollers you can use is planned later in the series, so I won’t go into detail here. Just know that the microcontroller is the computer and “brain” of the wearable.
(Figure 1: Squarewear, a mini programmable microcontroller great for wearables)
Sensors: The sensors gathers information about the environment or user. This includes light, temperature, motion (via acc) or location (via gps) of the environment, and heart rate (ECG), brain waves (EEG), and muscle tension (EMG) of the users. While some microcontrollers may come with basic sensors, advanced sensors may have to be obtained separately from a manufacture. I’ll dive into these more heavily in another post of our series.
(Figure 2: an EMG sensor that measures pulse rate connected to a battery-powered Arduino microcontroller)
Actuators: These are motor drives that are responsible for controlling the project. The most common are linear actuators used in basic disk drives and come with connectivity wires to power it from the microcontroller via USB. You will use the actuator to connect the microcontroller to programming script on that makes the wearable function. This particular tool is hard to understand, so I included a great video tutorial below on how an actuator (in this case a servo motor) is programmed:
Input and Outputs: Unlike the pins you would see on a traditional motherboard, microcontrollers will have eyelets and snaps made of metal which you can loop conductive thread through or connect cables with. You’ll want to have a few input and output cables handy as well as USB connectivity wires to assist you on your project.
Conductive Textiles: These textiles include thread, fabric, electrical paint, fabric for capacitive touch sensors, hook-and-loop for switches. What makes them unique is that the material contains metal within it which allows electrical currents to flow.
(Figure 3: a connected piece of conductive fabric that will measure hand motion)
Power: Some microcontrollers have an holder for coin batteries which are great for low-powered projects. Those with a standard JST connector are more versatile.
(Figure 4: a battery powered MSP430 Launchpad)
Networking: In order to communicate with devices, the internet, or other wearables, you will need a wifi connection.
Computer, laptop, or netbook: While the microcontroller does serve as the basic computer used in wearables, you’ll want to have another PC available to provide you with a UI and to code your scripts.
(Figure 5: Scratch script that will program the microcontroller connected by USB cables. Notice the connected actuator on the right)
Once you have a basic toolbox, you can dive into some really cool projects. Make Zine, Hackaday, Instructables, and Adafruit Industries all publish great books, videos, and tutorials on projects that cover anything from creating LED light powered signs to weather monitoring to even assembling your own open-source smart watch. If you are looking for materials, Maker Shed offers great prices on tools and networking tidbits, or you can visit your local hardware store. Just to make sure we have overall understanding to how things connect, I’ll be discussing microcontrollers in the next post of the series. Stay tuned for more ideas of which microcontroller you should include in a project and how to program it.