pebl
Firmware to clinical software for a neuromuscular assessment device.
pebl is a clinical-grade handheld neuromuscular assessment device built by pebl health inc., where I am the founding software engineer on a small team. The device fuses a load cell, a pressure matrix, an IMU, and a haptic actuator, and runs a short battery of tests. My work spans four repositories: ESP32-S3 firmware in C, a Rust and Tauri desktop app called PSL with a React frontend, a Python SDK, and an iOS companion app. The connecting thread is a custom binary wire protocol with CRC-16/CCITT framing, implemented byte-for-byte identically in C, Rust, and TypeScript so firmware, desktop, and phone all agree on the wire. PSL republishes device data into the neuroscience research ecosystem over Lab Streaming Layer and gRPC, and a clock-sync engine using min-RTT filtering and a weighted-least-squares drift model keeps multi-kilohertz sensor streams aligned. The hardware and the clinical science are my teammates' work; the software stack is mine.
Highlights
- Binary wire protocol (CRC-16/CCITT) implemented byte-identically in C, Rust, and TypeScript
- PSL desktop app: device discovery, multi-device dashboard, and live stream views
- Republishes device data to research tooling over Lab Streaming Layer, gRPC, and a Python SDK
- Clock-sync engine aligning multi-kilohertz sensor streams across devices
- iOS companion app with on-device DSP: FFT tremor analysis, Mahony AHRS, adaptive staircase