{"@context":"https://schema.org","@graph":[{"@context":"https://schema.org/","@type":"JobPosting","@id":"#jobPosting","title":"Principal Embedded Algorithms & Firmware Engineer

• Reproducible offline pipeline (Python / Matlab) for HR / RR / SpO with motion handling; first pass at BP / PTT.
• Data capture stack : synchronized PPG + IMU logs, simple labeling tools, ground-truth protocols.
• Firmware MVP on Cortex-M / ESP32 : sensor drivers, timestamping, buffering / streaming (BLE), low-power plan.
• Baseline report : signal quality, latency, and energy budget with a roadmap to on-device vitals.

Responsibilities

• Design & validate biomedical pipelines (PPG motion artifact reduction, baseline drift, sensor fusion with IMU).
• Derive vitals (HR / RR / SpO ) and explore BP via PTT; define calibration / quality metrics.
• Architect embedded firmware : drivers, DMA, double-buffering, storage / streaming, clock sync, power modes.
• Prepare filters / models for TinyML / CMSIS-DSP / NN; profile & optimize (fixed-point where needed).
• Guide hardware choices (AFE, LEDs / PDs, IMUs, antenna constraints); support bring-up and lab validation.
• Own data quality : capture protocols, ground-truth pairing, QA dashboards, and acceptance criteria.

• 5-8+ years across biosignal processing (PPG) and embedded firmware on Cortex-M / ESP32.
• Shipped something that lived on a human body (medical / wellness / sports).
• Proven motion artifact handling in the wild; calibration experience.
• Strong Python + C / C++; comfort with profiling / optimization on MCU targets.
• Lab chops : scopes, logic analyzers, PCB bring-up, AFE tuning, RF basics.

Edge ML (TinyML, CMSIS-NN, TFL-M), OTA, BLE / GATT design, antenna tuning, small-batch manufacturing test. Engagements and benefits

• Contract : 3-month SOW with clear milestones; option to convert to full-time.
• Compensation : competitive day rate / salary + equity option on conversion.
• Tools, dev kits, and lab access supplied as needed.
• Remote (EU / UK) with regular lab days in London.