Simbex is seeking a Senior Embedded Systems Engineer to own the full hardware‑firmware stack for a next‑generation IoT wearable platform. This is a dual‑discipline role: you will independently design and develop embedded hardware circuits and PCBs alongside production‑grade Zephyr RTOS firmware — from component selection and schematic capture through board bring‑up, sensor integration, and field deployment. The ideal candidate is a hands‑on engineer who takes end‑to‑end ownership in building sensor‑based hardware and firmware.
Essential Functions:
Electrical Engineering & Hardware Development
- Own hardware design from component selection and schematic capture through PCB layout review and design-for-manufacture
- Lead board bring‑up: power sequencing, peripheral initialization, signal integrity verification, and fault isolation
- Design and characterize low‑power analog front‑ends and power management subsystems for battery‑operated wearables
- Develop hardware test fixtures and produce electrical characterization reports
Firmware Architecture & Development
- Architect and deliver production Zephyr RTOS firmware on ARM Cortex‑M/R targets
- Author device drivers, BSPs, and devicetree overlays; implement sensor acquisition pipelines for IMU‑based impact detection
- Design low‑power state machines and event‑driven architectures for wearable operation
- Set firmware coding standards, CI/CD pipelines, and architecture guidelines for the team
IoT & Wireless Connectivity
- Implement BLE stacks for real‑time telemetry and configuration; design OTA update mechanisms via MCUboot
- Integrate cloud connectivity (MQTT/CoAP) and evaluate edge vs. cloud trade‑offs for impact detection
Signal Processing & Algorithm Integration
- Port impact detection algorithms from MATLAB or Python into constrained C/C++ firmware
- Apply sensor fusion (Madgwick, Mahony, complementary filter) for accurate head kinematics from multi‑axis IMU data
- Optimize DSP routines for speed and memory footprint on resource‑constrained targets
Testing & Quality
- Define and execute unit, HIL, and system integration test plans; build automated regression frameworks
- Maintain design documentation, traceability matrices, and test reports; support compliance activities
Required Qualifications:
- BS or MS in Electrical Engineering, Computer Engineering, Embedded Systems, or related field
- 7+ years of embedded development experience, including 3+ years on production‑shipped products
- Hands‑on EE skills: independently read schematics, perform board bring‑up, and debug hardware/firmware interaction
- Proficiency with bench instrumentation (oscilloscope, logic analyzer, power analyzer) for power characterization and debug
- Experience selecting microcontrollers, RF SoCs, and sensor ICs (IMU, accelerometer, gyroscope) for product designs
- Strong C/C++ in bare‑metal and RTOS‑based embedded contexts
- Demonstrated Zephyr RTOS experience: devicetree, Kconfig, module system, and west toolchain
- Experience with ARM Cortex‑M SoCs (Nordic nRF52/nRF53, STM32, or similar) and peripherals: SPI, I2C, UART, USB
- BLE firmware experience and familiarity with OTA update workflows (MCUboot preferred)
Preferred Qualifications:
- Sensor fusion algorithm experience (Madgwick, Mahony) and algorithm porting from MATLAB/Python
- Exposure to sports biomechanics, head impact research, or wearable athletic sensing
- Cloud IoT platform experience (AWS IoT Core, Azure IoT Hub) and embedded security (TLS/DTLS, secure elements)
- Multi‑core SoC development (e.g., nRF5340) or experience in a regulated/safety‑critical product environment