Biofeedback sensor integration
Polar H10 Work
The Polar H10 is a practical chest-strap sensor for making heart rhythm, RR intervals, ECG, and accelerometer data available to XR and research tools. My work around it is not one app. It is a set of minimal signal packages, public contracts, companion utilities, Quest broker paths, Android checks, Unity integration work, and research-calibration tools for keeping biosignal routes visible enough to debug.
Purpose
A signal route, not a gadget demo
A biosignal is only useful in an XR system when the route is explicit. The important questions are practical: which device owns the Bluetooth connection, whether the stream is standard heart-rate data or raw Polar PMD data, how the samples are timestamped, whether the headset or Windows machine is observing, and which schema a downstream consumer can trust.
The public work keeps those questions separate. Polar H10 Signals owns minimal source packages for HR/RR, PMD ECG, and PMD accelerometer payloads. Rusty XR owns broader reusable data models and decoders. The Quest broker owns headset-side stream publication. The Windows companion owns operator-side capture and planning. Android tools own phone-side Bluetooth checks and diagnostics. Unity work shows how direct BLE and broker-routed paths can be compared inside a Quest scene.
The intent is biofeedback engineering for research and creative XR systems: inspectable streams, clear ownership, reproducible diagnostics, and public protocol notes. It is not medical software and it does not make clinical claims.
Public boundary
- Reusable schemas, decoders, command shapes, and diagnostics are public-facing.
- Raw captures, local run artifacts, study identifiers, and private stream names stay out of public pages.
- Polar PMD streams such as ECG and accelerometer are treated as single-owner during live tests.
- Public examples should keep app-specific simulation logic separate from sensor transport.
Signals in scope
- Standard BLE Heart Rate Measurement notifications for BPM and RR intervals
- Battery and service visibility checks for setup diagnostics
- Polar PMD ECG frames when a raw cardiac waveform is required
- Polar PMD ACC frames for chest-motion and breathing-related experiments
- LSL, OSC, broker, and local JSONL routes for downstream tools
Project map
Where the H10 work lives
These are the public-facing layers of the current Polar H10 work. Some implementation history remains private or project-specific; the public page describes the reusable behavior and documented boundaries.
Polar H10 Signals packages
Polar H10 Signals is the smallest public integration surface: a Rust protocol crate, a .NET protocol package, an Android/Quest Kotlin source bridge, and Unity event DTOs. It is not a full app. It gives host apps source-anchored command builders and decoders for standard HR/RR plus PMD ECG and accelerometer frames.
Rusty XR data contracts
Rusty XR carries framework-neutral BLE, LSL, and Polar models. The
public rusty-xr-polar surface includes Polar H10 GATT UUIDs, PMD
command builders, Heart Rate Measurement decoding, ECG frame decoding,
uncompressed ACC frame decoding, and LSL stream schemas.
Quest broker path
The Quest broker can publish Polar-shaped diagnostic stream events for HR/RR, ECG, and ACC. This gives headset and desktop consumers a stable stream contract before every app shell has native Bluetooth, LSL, or deployment details finalized.
bio:polar_hr_rrfor standard heart-rate notificationsbio:polar_ecgfor Polar PMD ECG payloadsbio:polar_accfor Polar PMD accelerometer payloads- Quest broker APK source
Windows capture and planning
Rusty XR Companion includes a Windows-only H10 capture service using WinRT Bluetooth LE APIs. It can read battery metadata, subscribe to heart-rate and RR notifications, optionally start PMD ACC streaming, write JSONL witness records, and plan whether PC, Quest, dual HR/RR, or two-sensor comparison owns a live test.
Android phone diagnostics
The Android companion work keeps phone-side protocol checks in the phone app rather than Rusty XR core. The public Polar slice scans for the H10, connects long enough to discover services, reads the Battery Level characteristic, reports Heart Rate and PMD visibility, and closes cleanly.
Unity Quest integration
The Unity Quest work uses a scene-authored BLE and Polar graph, a headset HUD, runtime permission handling, direct Polar routing, and broker-routed comparison paths. The important public idea is the split between direct Unity ownership and broker ownership of the same H10 PMD stream.
- Stable scene objects for permission, BLE readiness, scan/connect, and HUD state
- Direct route records HR/RR and decoded PMD ACC/ECG frames
- Broker route records the same signal family as stream events
Viscereality research tooling
Viscereality uses H10 data as part of breath and cardiac biofeedback research. The public boundary is the system idea: combine chest-strap heart rhythm or accelerometer data with phone, Quest, and browser tooling while keeping research claims and raw recordings bounded.
Use cases
What this makes possible
The useful result is not simply that a headset, phone, or Windows machine can see the H10. The useful result is that a project can choose a route deliberately and still produce comparable evidence: local capture on Windows, headset-owned PMD, phone-side Bluetooth diagnostics, LSL observation, OSC or broker bridge traffic, and Unity-side direct-vs-broker comparisons.
That is what lets H10 work support visual-state experiments, breath-estimator calibration, cardiac timing, XR biofeedback, and tooling diagnostics without mixing every prototype into one private runtime.
Reusable offerings
- Minimal Rust, .NET, Android/Kotlin, and Unity source surfaces for host apps
- Protocol-level documentation for BLE, PMD, and LSL stream shapes
- Quest broker event names and payload conventions for H10-like signals
- Windows capture records for local evidence and plotting
- Android smoke checks for sensor presence, battery, and service visibility
- Unity scene patterns for permission, connection, HUD, and signal comparison
Earlier protocol reference
An earlier public PolarH10 reference site documents protocol notes, formula sheets, and implementation background. Newer Rusty XR work uses those notes as reference material while keeping current contracts in the Rusty XR and companion repositories.
References
Public docs and repositories
Mesmer Prism projects
- MesmerPrism. "polar-h10-signals." Minimal source packages for HR/RR, PMD ECG, and PMD accelerometer integration.
- MesmerPrism. "Rusty-XR." Public repository for reusable XR contracts, examples, and docs.
- Rusty XR. "BLE, LSL, and Polar H10 Pipeline." Public routing and decoder notes.
- MesmerPrism. "Rusty-XR-Companion-Apps." Windows companion and operator tooling.
- Rusty XR Companion. "Polar H10 Windows Capture." Public capture-service boundary.
Protocol and vendor references
- MesmerPrism. "PolarH10." Earlier independent protocol and implementation reference.
- Polar Electro. "Polar BLE SDK." Public open-source SDK used for protocol cross-checking.
- Android Developers. "Bluetooth permissions." Android BLE permission reference.
Polar and Polar H10 are trademarks of their respective owners. This work is independent and is not affiliated with or endorsed by Polar Electro.