Open Source · Open Hardware

Prosthetic Sensors
Open for All
Humanity

OpenMuscle is building affordable, open-source pressure myography sensors that predict finger movements using machine learning. No patents. No paywalls. Just technology that belongs to everyone.

Explore on GitHub How It Works
60
Sensors (FlexGrid)
~$45
Per Device
MIT
Licensed
Real FlexGrid-64 holdout data (683 samples)

What is OpenMuscle?

An open-source biosensing ecosystem for wearable prosthetic control. We use pressure myography — not EMG — to detect muscle contractions and predict individual finger movements in real time.

Open Hardware

ESP32-S3 microcontrollers, custom flexible PCBs, 3D-printed enclosures. FlexGrid packs 60 sensors into a 15×4 grid at just 3mm thick. All designs released under CERN-OHL-S v2.0.

Machine Learning

Random Forest Regressors predict finger movements from pressure data. The LASK5 labeling device captures ground-truth training data. Python pipelines process UDP sensor streams in real time.

Community Driven

Collaborators worldwide: Ultimate Robotics (EMG, Ukraine), Delta Robotics (artificial muscles), PCBWay sponsor, devEco group. Featured on Hackaday and Electromaker.

How It Works

1

Wear

FlexGrid wraps around the forearm with 60 pressure sensors detecting muscle topology changes

2

Sense

Sensors capture pressure myography data and transmit via UDP over WiFi from ESP32-S3

3

Learn

LASK5 captures labeled finger positions. Random Forest models train on paired sensor + label data

4

Predict

ML model predicts individual finger movements in real time from raw pressure readings alone

Deep Dive into the Technology

Explore the Repos

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OpenMuscle-FlexGrid

60-sensor (15x4) forearm band with flexible PCB and ESP32-S3. Current flagship hardware.

Hardware CERN-OHL-S

OpenMuscle-LASK5

Label Acquiring System K5 — handheld device for capturing ground-truth finger positions for ML training.

Hardware ML Training

OpenMuscle-Software

Python & MicroPython codebase for data collection, preprocessing, and Random Forest finger prediction.

Python MIT
“
An amputee couldn't take home a prosthetic because of proprietary restrictions. That's when I decided — this technology needs to be free for everyone.
Tory
Founder, OpenMuscle
Read the full story

Help Us Build the Future of Prosthetics

We need testers, developers, and believers. Whether you can wear a sensor, write Python, or just spread the word — there's a place for you.

Get Involved Star on GitHub