This medical-device project covered prototype recovery, system-architecture redesign, firmware development, EMC and safety testing, production validation, and field support. I connected customer requirements with hardware, firmware, mechanical, factory, and third-party teams to improve reliability and move the platform toward repeatable production.
First-generation firmware and pilot-production improvements
The first-generation prototype used Parallax Propeller MCUs and the Spin language. I managed pilot-production progress and improved the firmware:
- Ported the Spin development flow from Windows to macOS and Linux with the OpenSpin compiler, then introduced Git for cross-platform collaboration and traceability.
- Improved UART communication to reduce interference between wireless and peripheral devices.
- Fixed a CPU tick-overflow defect so the firmware could operate reliably beyond 24 hours.
Hardware and power-architecture redesign
For the next generation, I led cross-functional customer support, created the hardware-verification plan, and coordinated internal and external engineering resources. The redesign included:
- Raising the system backbone from 18 V to 24 V to increase power margin and reduce voltage drop over long cables.
- Reworking power distribution for motors, high-brightness lighting, control logic, and peripheral modules.
- Designing the initial shared motor-control schematic with overcurrent protection, PWM control, and an emergency-stop path, then working with hardware engineers through completion.
- Expanding the system into a modular multi-board architecture using RP2040 MCUs and Raspberry Pi CM4, with reusable firmware and interfaces for power, motion, displays, controls, and future expansion.
- Correcting long motor-power traces and other layout issues to improve stability and reduce EMI.
Connected software and firmware platform
I helped evolve the product from an offline standalone system into an IoT platform with centralized management, remote monitoring, upgrades, and integration with other devices.
- Introduced Embedded Linux kiosk mode and remote upgrades, reducing the need for on-site disassembly and maintenance.
- Established a shared RP2040 and Raspberry Pi CM4 development environment to maximize code reuse across boards.
- Replaced a simple serial/wireless keycode protocol with CANbus, RS232, and MessagePack, adding error checks and packet-loss detection for more reliable motion control. I designed and implemented the initial protocol before handing it to the firmware team for continued development.
- Introduced CI for firmware version management and quality control.
- Built a KiCad Python/SQLite tool to consolidate multi-board BOMs and reduce spreadsheet copy-and-paste errors.
- Built cloud time-series storage and dashboards for production and field telemetry, error logs, remote monitoring, and fault diagnosis.
EMC, safety, and production validation
I worked with the hardware team and third-party laboratories to investigate EMI, EFT, surge, and ESD failures across power architecture, PCB layout, shielding, cable routing, grounding, filters, chokes, and isolated DC/DC modules. I also supported assembly reviews, diagnostic workflows, recurring-defect analysis, urgent part revisions, and remote system troubleshooting, closing the loop among laboratory measurements, engineering documentation, factory results, and field feedback.