Expanding Gesture Control with the Myo
The Myo armband is a relatively recent innovation in touch free technology control from Thalmic Labs, using proprietary sensors that monitor the electrical activity in the user’s muscles to produce a digital response.
These sensors, embedded in 8 rubberised modules, read the muscles electrical impulses when the user makes specific movements and hand gestures, these are relayed via Bluetooth to the command device such as a mobile phone or a computer, that it is synced with.
EMG and IMU
There are two kinds of sensors in the armband that are designed to track movements and hand gestures, 8 electromyographic sensors, and one 9-axis inertial measurement unit, both of which initially proved expensive to develop. The inertial unit contains a gyroscope, accelerometer and a magnetometer, which are all 3-axis variants. When used together, these two sensor types can register a near-infinite amount of physical inputs.
Due to the Myo’s flexible form factor, it’s constructed of individual circuit boards instead of one PCB, this helps maintain separation around the forearm and allows it to bend properly when being used. The 8 ‘pods’ of the device are designed to be a snug fit around the user's arm in order for it to function correctly and is one-size-fits-all. A flexible rubber membrane construction maintains the integrity of the Myo, and the complex electronic modules are connected through this flexible membrane in a daisy-chain fashion.
The armband gets it power via a built-in lithium-ion battery that is charged using a micro-USB cable, and on average a single charge will provide enough power to run the Myo for a whole day. Technical features include dual indicator LED’s, ARM Cortex M4 Processor, and haptic feedback with short, medium and long vibrations.
Arms and Arduino
The list of applications for this multi-platform product is growing rapidly as more and more developers adopt the technology. The Myo can be used to control the playback of music from popular apps like Spotify, making a fist and rotating your arm right or left can turn the volume up or down, and waving left or right will change tracks. You can interface and control your laptop, pilot a drone or simply control your latest presentation. There have also been some interesting projects using the Myo armband with an Arduino based board, which you can find here
Recently, Myo applications began making headway in the medical field with interesting developments using artificial limbs, it’s apparent that the possible avenues for this unique product are only restricted by our imagination and may have considerable scope in helping the less able bodied.
If you want to explore the outputs from the sensor in the device, there is an app on the Myo Market called Myo Data Capture. This app produces 4 CSV files that can store all of the information that is streamed, including, data from the accelerometer, gyroscope, orientation, orientation in Euler angles and the electromyographic sensors.
The Myo armband has the potential to revolutionise how humanity can interact with machines and other technology, with new and exciting applications being created as fast as you can think of them, the future does indeed appear bright for this particular device and for the applications it can inspire.
For more information about the Myo armband, click here.