_”Use the power of your muscles to interact with the world
Mumai is an open-source muscle-machine interface that connects your body to any kind of electronic or mechanic device through the myoelectric (EMG) signals generated by your muscles.
The uses of this interface are limited only by your imagination. It can be used to control assistive robotic devices such as prostheses or exoskeletons. Alongside some of the freely available machine learning libraries (Scikit-learn, TensorFlow, Dlib…) it can be used to implement a gesture recognition controller to interact with electronic devices such as computers or smartphones. In the sports field, it can be used to optimize the level of exercising. At a university level, it can be used in biosignal processing courses, working as a biomedical instrumentation device. How this device will be used depends on you.
The problem
Electromyography, or EMG, is a technique from the medical field that comprises the recording and the study of the electric signals generated when a muscle contracts. EMG is widely used in clinical applications: kinesiological studies, medical diagnosis or rehabilitation, among others. Also, EMG is the preferred method to control robotic prosthesis or exoskeletons, since using the user’s cognitive processes is a natural and intuitive way of interacting with such devices. Besides these applications, EMG can also be used in hands-free computer control, physical training optimization, interactive art…
Professional EMG systems are very expensive, cumbersome (with lots of cables connecting the electrodes to the amplifier) and complex, and for this reason their use is usually limited to hospitals or professional laboratories. Although there are some portable and simpler professional EMG systems, they are also quite expensive to be used by hobbyists or research labs with a moderate budget.
The solution
The aim of this project is to develop an affordable and open-source wearable wireless network of EMG sensors that can be placed on any muscle. With this project my intention is to develop a hacker-friendly biofeedback interface to control devices ranging from computers or smartphones to robots with EMG signals. It can also be used simply as an instrumentation system to view and analyze the acquired EMG data. Although it probably cannot be compared with professional systems in the market, the EMG signal acquisition circuit is carefully designed, using low-noise components and techniques for active suppression of mains hum. Wireless communication allows the use of multiple sensors without the large number of cables that this type of devices usually have. Also, the wireless architecture allows for a great flexibility since there is no fixed number of acquisition channels.
Each EMG sensor is connected to a ESP8266 module, forming a Mumai node. The nodes send the EMG data through WiFi to a computer, smartphone or other devices, such as a robot or a home automation system. The following diagram summarizes how this interface works.”_