CleverHand

CleverHand is an open-source, modular Human-Machine Interface (HMI) system designed for the acquisition of biosignals (EMG, ECG, EEG, etc.) and the delivery of sensory feedback (electrotactile, vibrotactile, visual, etc.). The system is intended for use in research and educational settings, as well as a platform for the development of assistive technologies, prosthetics, and exoskeletons.

The project is in the early stages of development, so expect some debugging and troubleshooting before it is ready for use.

If you are interested in contributing to the project, feel free to raise issues, submit pull requests, or contact us directly.

CleverHand

Module	Bracelet factor

Repository structure

• hardware contains the hardware design files (KiCad)
• firmware contains the firmware for the communication between the modules and the host
• software contains the software for the communication between the main module and the host (GUI, LSL, python, C++)
• tools contains the tools for the configuration of the CleverHand device or plotting the data:
  • Cleverhand-configGUI is a simple GUI to configure the CleverHand device and stream EMG samples.
  • clvhd_lslplotter is a simple GUI to plot the data streamed from the CleverHand device using LSL.

Features

• Modular Architecture

  Up to 32 integrable modules, each containing 5-8 surface electrodes embedded directly into the PCB.

• Adaptable Addressing System

  Module addresses based on their physical position in the chain, eliminating the need for hardcoded addresses.

• High-Quality Signal Acquisition Samples EMG signals at a rate of 4 kHz with 24-bit resolution.

• High-Density Design

  Each module measures 20mm x 20mm and houses five 3mm x 18mm electrodes.

• Portability

  Offers both wired (Ethernet) and wireless communication options.

• User-Friendly Interface

  Comes with an intuitive GUI for easy parameter configuration, real-time visualization, and data streaming via LSL.

Study

Details

Motivation

Electromyography (EMG) is a technique used to measure the electrical activity of muscles. It is widely used in the field of human-machine interaction, as it provides a non-invasive method of monitoring muscle activity. For example, EMG can be used to control prosthetic devices, allowing amputees to regain some of their lost functionality. EMG can also be used to control exoskeletons, allowing for the restoration of motor function in patients with neurological disorders. In addition, EMG is used in the field of sports science to monitor muscle activity during physical activity.

Context

Current devices used for EMG signal acquisition are often bulky and expensive or lack the necessary features to meet the needs of researchers and clinicians.

Wearable EMG devices

Device	Price	Electrodes	Sampling rate	Resolution	Comments
Myoband	200$	8 bipolar electrodes	200 Hz	8-bit	It was very handy and easy to use for experiments as the users just had to put it on their arm and it was ready to use. Unfortunately, the Myoband is no longer available for purchase.
MyoWare EMG Sensor	40$	3 bipolar electrodes	200 Hz	10-bit	The MyoWare EMG Sensor is a low-cost EMG sensor that can be used to measure muscle activity. It is a good option for prototyping, but it lacks the necessary features for research and clinical applications.
Delsys Trigno Avanti	2000$	16 bipolar electrodes	2000 Hz	16-bit	The Delsys Trigno Avanti is a high-end EMG system that offers a wide range of features. It is a good option for research and clinical applications, but it is expensive and not very portable.

Non-wearable EMG devices

Device	Price	Electrodes	Sampling rate	Resolution	Comments
OT Bioelettronica Sessanta Quattro	10000$	64 monopolar electrodes	2000 Hz	24-bit	The Sessanta Quattro is a high-end EMG system that offers a wide range of features. It is a good option for research and clinical applications, but it is very expensive.
Delsys Trigno Wireless System	?	32 monopolar electrodes	?	?	The Trigno Wireless System is a high-end EMG system that offers a wide range of features. It is a good option for research and clinical applications, but it is very expensive.
OT Bioelettronica Muovi+	25000$	4x32 monopolar electrodes	2000 Hz	24-bit	The Muovi+ is a high-end EMG system that offers a wide range of features. It is a good option for research and clinical applications, but it is very expensive
OT Bioelettronica Quattrocento	50000$	382 monopolar electrodes	2000 Hz	24-bit	The Quattrocento is a high-end EMG system that offers a wide range of features. It is a good option for research and clinical applications, but it is very expensive.

Approach

Our system features a modular architecture, allowing for the integration of 1 to 32 modules. Standard modules house ADS1293 or ADS1298 EMG acquisitions chip, enabling the sampling of 3 to 8 channels of EMG data at a rate of 4 kHz with a 24-bit resolution.

To achieve a high-density design, the bottom layer of the PCB contains eight gold-plated areas (3mm x 18mm) that can serve as electrodes. This high-density design, with a module size of 20mm x 20mm, facilitates precise and detailed analysis of muscle activation patterns, especially in applications that require high spatial resolution.

To ensure the versatility of the modules it is also posible to use the gold plated electrodes to mount adpters for other type of electrodes (jack connector, snap connector, flex electrodes).

The addressing system employed by the device is adaptable, with the address of each module determined by its physical position in the chain. This design eliminates the need for hardcoded addresses and simplifies the overall usage.

Module	Price	Electrodes	Sampling rate	Resolution
CleverHand	200$	16x8 monopolar/bipolar electrodes	4 kHz	24-bit

Additional features

Feature	Description
Modular	1 to 32 modules per device
Visual	2 RGB LEDs per module
IMU	Can be equipped with an IMU module
Electrotactile	Can be equipped with an electrotactile module
Vibrotactile	Can be equipped with a vibrotactile actuator
Communication	Wireless (Bluetooth, WiFi, LORA, ...) or wired (USB, Ethernet, ...)
Attachments	Standard, bracelet, mesh
Interface	GUI, LSL, python, C++

Diagram