openEMSstim is a research kit based on Arduino
This is the openEMSstim, a research kit based on an Arduino Nano that modulates the amplitude of Electrical Muscle Stimulation (EMS) signals and integrates nicely with wireless projects such as wearables.
This is a kit for researchers to investigate electrical muscle stimulation (EMS). This leverages the simplicity of Arduino development with safe muscle stimulation units. The board itself is decoupled from the EMS signal path and just modulates the amplitude of the signal. Researchers can pair this up with their medical signal generators and develop wearable applications, such as bracelets that use EMS. The board is also controllable via Bluetooth and compatible with any BLE device you have (such as your smartphone). It includes also a whole range of APIs such as Android, IOS, node.js, python, processing and Unity3D.
*All pictures were taken at the UIST 2016 Student Innovation Competition which was entirely organized using the openEMSstim as an open-source technology for all student teams to work with. These are actual working prototypes built by the students of the competition.
EMS (electrical muscle stimulation) is a recent addition to computer interfaces. It allows a direct connection between a user and a computer through the user's muscles. It is applied for rehabilitation purposes but also for interactive applications such as creating immersive sensations in VR, or teaching you how to operate devices you have never used, or even help you solve problems. But there was not easy way to get researchers into using EMS without starting to hack existing medical devices, which is not a safe approach. So the openEMSstim, an Arduino-based board that pairs up to an existing medical device to allow for wireless operation of EMS signals, was created by Pedro Lopes. A few months of development, mainly attributed to the hard work of Max Pfeiffer and Tim Düente (from the University of Hannover at the chair of Prof. Michael Rohs) designed the initial circuitry. Then Pedro and his team got together for hand soldering and baking about 40 of these PCBs (some of them they even milled ourselves).
The board is based on decoupling the EMS signal and the control. They use digital potentiometers to regulate the amplitude of the EMS signal but these are galvanically isolated from the arduino signal. Hence you get two separate circuits, making it safer to use. Pedro wanted other researchers to be able to investigate EMS without having to start from scratch like he did, that’s why he chose an open source. If you are interested in building one yourself, there’s a whole tutorial here, step by step: https://github.com/PedroLopes/openEMSstim/blob/master/start-here-tutorials/1.getting_started_step_by_step.md