In celebration of #MarchIsForMakers, an initiative to get more coders interested in building hardware, I started this 4-part introduction to wearable technology. Click here to see Part I of the series Getting Started with Wearables, and here for Part II on Finding the Right Microcontroller.
Putting Together Your Toolkit
Wearable tech is small enough to be worn, so your average hammer and nail set won’t do when making something purposed for micro-scale. There are a variety of different tools and sensors you will need to be familiar with in order to get started. Even if you don’t have a project in mind, it’s best to know what tool or sensor to use, for what purpose, and what they do. In today’s post in the series, I have put together a short guide to help you know what’s what :
Circuit: A circuit is a series of electronic components connected on a board of strip using wires. On a circuit board, conductive tracks are etched into it using copper sheets to allow for the flow of electricity.
Breadboard: A board of connections prearranged and represented by a hole. The holes have a metallic spring underneath that links them by column. Breadboards are used to house circuits. For example, you connect an LED to the breadboard using a resistor (the power control source).
Jumper wires: These are wires used to connect sensors and wireless modules. Jumper wires are female and connect to a male pin terminator in a sensor or modules that allow electrical current control. The pins can also be used to connect to a breadboard to house circuits.
(Figure I: An arduino uno microcontroller is linked to a breadboard using jumper wires. Notice the USB cable on the upper left that can function as a power source or laptop connection. The breadboard also has a red DOF motion sensor attached to it ready for programming. Image Source: Wikipedia Commons)
Switch: A component that can open or close an electrical circuit connection.
LED: A small source of light based on a semiconductor
Resistor: A resistor limits the electricity that flows to a LED keeping it at an optimum amount of power.
Accelerometer: A motion sensor that measures acceleration forces, in particular, g-force, which determines rate of change. Accelerometers in your wearable projects helps to determine and analyse if the device is moving and/or tilted.
(Figure II: Clime is an example of an environmental sensor that tracks humidity, light, temperature, and movement. Image source: climesense.com)
Oximeter: A type of electro-cardigraph (ECG) reader that measures blood oxygen and pulse rates.
Skin Conductance sensor: A sensor that measures body temperature and how much you sweat. These are most useful in exercise tracking wearables that can track how many calories burned during a workout based on hydration, temperature, and acceleration levels.
Environmental sensors: These type of sensors can measure humidity, temperature, and read UV rays.
EEG sensors: An electro-encephalograph reader is leveraged in wearables to provide certain types of biofeedback to the user. Using powerful algorithms, these sensors can measure brainwave activity and can be programmed to respond to user attention and meditative states, common for tracking sleep activity.
Light sensors: A type of optical sensor that measures ambient light. Light sensors can be connected to LEDs which allow for greater user control.
After researching, I found most of the tools to range in price from $2-$15 USD, which is not bad considering scale. Depending on strength, flexibility, power control, and programmable options, sensors can range anywhere from $5 for the most basic type of magnometer to $100 for an elite EEG sensor. It’s up to you to decide how much you want to invest, but a great option would be to go for a project kit which has the microcontroller, tools, and sensors already included. In the next and final post in this series, I’ll go over some project kits that are both affordable and great for beginners available.