Neural Face Interface for Spatial Computing
A silicone facial gasket with ten flat dry Ag/AgCl electrodes (8 active + REF + BIAS) that snaps onto your VR headset. A strap-mounted IronBCI box digitizes frontal EEG, EOG blinks, and facial EMG at 24-bit / 250 SPS and streams over Bluetooth LE 5 into PiEEG Cloud, pieeg-server, VRChat OSC, or BodyPress.
[01 · XR ARCHITECTURE]
Trace the gasket from dry Ag/AgCl pads to avatar and scene
Pick an XR subsystem to inspect how the 10-electrode facial mask, the IronBCI BLE 5 front-end, expression decoders, and OSC/WebXR outputs connect. Hover any specification row to highlight its nodes.
Live output preview
Values in the live panel are simulated to illustrate the runtime contract of each XR surface.
[02 · 4 HEADSET CONNECTION ROUTES]
Four ways to get BLE 5 from the mask into your headset
Stock standalone headset browsers disable Web Bluetooth. Pick the path that matches your session: desktop Web Bluetooth with Link mirroring, a local pieeg-server over Wi-Fi, UDP OSC into VRChat, or direct on-headset BLE via BodyPress / ARM64 Chromium.
Cloud on PC + Desktop Mirror
Desktop Chrome and Edge support Web Bluetooth natively. Pair PiEEG XR or PiEEG XR-16 directly at cloud.pieeg.com, then bring your PC desktop into the headset over USB-C Link, Air Link, Virtual Desktop, or Steam Link.
- 1Power the strap-mounted IronBCI box from a 5 V USB-C battery bank (LED on, advertising as PiEEG XR).
- 2On your PC, open cloud.pieeg.com/lobby in Chrome or Edge, click Connect, and pair PiEEG XR over Web Bluetooth.
- 3Mirror your PC desktop into the headset and launch Face Trainer v2, Neural Flight, or Avatar Studio.
https://cloud.pieeg.com/lobby # Click Connect → PiEEG XR (8 ch) or PiEEG XR-16 (16 ch)
[03 · HARDWARE EDITIONS, DEMOS & EXPERIENCES]
Two XR editions built around the open IronBCI front-end
Both editions share the same silicone facial gasket, strap-mounted STM32WB + ADS1299 conversion box, and 5 V USB-C battery supply. Choose 8 channels for facial EMG, blinks, and frontal EEG, or 16 channels when your paradigm also needs occipital visual-cortex electrodes.
8 ch + REF/BIAS · BLE 5PiEEG XR
10 dry Ag/AgCl padsSilicone facial gasket with eight active electrodes over the forehead, temples, and cheeks plus REF and BIAS. Designed for facial EMG expression decoding, EOG blink/gaze detection, and frontal EEG monitoring.
16 ch (8 Face + 8 Occipital) · BLE 5PiEEG XR-16
Dual ADS1299 · +8 visual cortexAdds eight rear head-strap electrodes over the visual and parietal cortex to the 8-channel facial gasket. Enables posterior alpha reactivity, SSVEP, and visual ERP paradigms alongside facial EMG.
| Specification | PiEEG XR (8-Channel) | PiEEG XR-16 (16-Channel) |
|---|---|---|
| Active Channels | 8 channels + REF + BIAS (10 dry Ag/AgCl pads on facial gasket) | 16 channels + REF + BIAS (8 facial gasket pads + 8 visual-cortex strap sensors) |
| Analog Front-End | Single 24-bit TI ADS1299 · 250 SPS · 1.0 µVpp input-referred noise | Dual daisy-chained 24-bit TI ADS1299 · 250 SPS · 1.0 µVpp noise |
| Wireless & MCU | STM32WB dual-core (Cortex-M4/M0+) · BLE 5 · advertises as 'PiEEG XR' | STM32WB dual-core (Cortex-M4/M0+) · BLE 5 · advertises as 'PiEEG XR-16' |
| Signal Coverage | Facial sEMG micro-expressions, corneal-retinal EOG blinks/gaze, frontal EEG | All XR-8 facial/frontal signals + posterior occipital/parietal EEG (O1, O2, Oz, POz, Pz…) |
| Power & Mount | 5 V USB-C battery bank or headset battery · 4-buckle snap-in gasket + strap box | 5 V USB-C battery bank or headset battery · 4-buckle snap-in gasket + rear strap sensors |
Starter XR Experiences & Decoders
Every experience runs client-side in cloud.pieeg.com or locally from pieeg-server (MIT licensed).
Face Trainer v2
Common-Average Reference across 8 channels, 40-D time/spectral feature vector (200 ms @ 12 Hz), and Leave-One-Rep-Out cross-validation with per-electrode importance bars.
Avatar Neurofeedback Studio v2
Two-state contrastive calibration (20s quiet baseline vs 20s target state) ranks all channel × band features by within-session Cohen's d and wires them to VRM blendshapes.
Neural Flight (WebXR)
First-person procedural flight in WebXR where sustained focus drives lift and climb rate. Starts in autopilot preview and switches live in the headset.
VRChat OSC · Brain Regions
Partition channels into custom groups (Frontal, Zygomatic, Occipital) and stream rolling-normalized [0, 1] float parameters to VRChat avatars and chatbox.
Recorded Hardware & Avatar Sessions
PiEEG XR overview
Face interface mounted on a headset, streaming biosignals into avatar control.
Headset test with PiEEG dashboard
Live neural signals from the XR gasket into the PiEEG dashboard.
Avatar studio
Facial EMG and brain state driving a live avatar.
[04 · FIELD RESEARCH, VR PRESS & ECOSYSTEM]
Tested in VR sports performance and covered by global XR press
From athlete neurophysiology drills in virtual reality to independent reviews in the US, Japan, Germany, and the UK, PiEEG XR is built as an inspectable instrument for spatial computing.
PiEEG XR in sports research
“PiEEG XR is enabling us to gain a deeper insight into our immersive experiences, adding a neurophysiological dimension to the study of how athletes respond during specific training tasks. Its integration with virtual reality environments opens up new possibilities for objectively investigating what happens whilst performing different exercises and how the response changes in the face of varying demands. Although we are still working on methodological optimisation and signal quality control, it is so far proving to be a tool with great potential for sports-related research.”
Independent VR & Hardware Press Coverage
International coverage of PiEEG XR across dedicated virtual reality and hardware publications.
“This Quest 3 Accessory Makes Your VR Avatar Expressive Without Face Tracking”
Covers PiEEG XR as an open-source biosignal face interface that trains facial expression detectors and maps focus and sEMG into real-time VR avatar control without optical face-tracking cameras.
“The BCI device 'PiEEG XR,' which attaches to a VR headset and is controlled by brainwaves, has launched a crowdfunding campaign”
Japanese and English coverage by the MoguLive editorial team detailing Emotional Sync, Neural Interaction, the Focus-to-Action API, and the 250 SPS 24-bit BLE 5 IronBCI hardware stack.
“For VR: PiEEG XR measures brain activity in real time”
Technical hardware breakdown by Silvio Werner covering the replacement facial cushion, dry electrodes, 250 SPS wireless Bluetooth streaming for standalone headsets, and native VRChat compatibility.
“Revolutionising Avatar Control: PiEEG's Brain-Computer Interface for Quest Headsets”
Highlights how a snap-on facial gasket brings low-cost biopotential sensing to standalone VR headsets for developers, gaming experiments, and cognitive research.
VR Protocols, Engines & Companion Hardware
UDP :9000 · /avatar/parameters/*Global or per-region normalized band powers & fEMG blendshapes
immersive-vr · immersive-arIn-browser 3D neurofeedback scenes (Neural Flight, XR Wave View)
Native Headset BLE AppOffline 3D signal monitoring & per-channel electrode health
WebRTC P2P → Local Bridge5 MB Rust bridge outputs named OSC channels on 127.0.0.1
pieeg-server --lslStream raw 250 SPS µV to OpenViBE, MNE-LSL, and LabRecorder
4 dry sEMG + 6-axis IMUCompanion wrist strap for synchronized hand gesture + face XR
El Abbassi, Y.; Rakhmatulin, I. PiEEG XR: A WebXR Brain-Computer Interface Platform for Neural-Adaptive Avatar Control in Mixed Reality. Preprints 2026, 2026060016.
PiEEG XR is a research and developer kit, not a medical device. Operate strictly from a 5 V battery bankor the headset's internal battery over USB-C. Never connect the board to mains wall power while worn.
Snap the gasket onto your headset or test in Mock Studio
Back PiEEG XR on Kickstarter, inspect the 8-step interactive setup and noise verification guide, or open PiEEG Cloud right now to test Face Trainer v2 and Avatar Studio.