Jonathan Leary

San Diego, California US

Dexcom

Dexcom: Mechanical Engineer II

• Led testing of Dexcom's next generation wearable platform from POC to V&V handover.
• Led small team using NUD/ECO and risk-based approach to prioritize and execute characterization, cliff, and reliability testing at component and system level.
• Test planning, p-diagrams, risk register, documentation etc.
• Developed tests...
• Developed equipment...
• Electro-mechanical debugging of complex wearable systems. Worked as part of several mission-critical 'Tiger Teams' to find and prove root cause on issues such as Environmental Stress Cracking, Adhesive Delamination, Rapid Voltage Decline/Brown-outs, Battery Electrolyte leakage, and other product performance related issues.
• Developed Windows software for NFC communication and test specimen preparation and tracking, DUT data parsing and automated analysis using SAS JMP API including normalization and filtering, chart generation, distributions, T-tests, etc.
• Developed novel methods and semi-automated equipment for attaching 0402 passive SMD components to end of 0.25mm dia. coax wire to emulate specific test loads, without the use of solder or significant thermal exposure.
• Measurement routines and fixtures
• Instron method and fixture development, including advanced uses of strain input to capture dynamic analog electrical data from DUT, and Digital I/O to trigger and sync external measurement equipment such as DMM, Oscilloscope, or SMU during compression/tensile/shear testing.
• Highly skilled with use of optical microscopes and physical tools such as scalpels, tweezers, soldering irons, hot-plates, alongside CAD/CAM systems such as bench-top milling machines, 3D-printing, automated epoxy and adhesive dispensing equipment, to dissect and debug devices, prepare novel device configurations for test, and enable rapid prototyping of small electro-mechanical devices.
• Use of embedded systems to enable high-n testing with limited expenditure, e.g. recording data to SD card from many sensors on a shared I2C or SPI bus, logging current, voltage, temperature, humidity through various environmental conditions. Development of a small form-factor multi-sensor BLE enabled PCBA to measure temperature, ambient pressure, humidity, condensation droplet formation inside a thumbnail sized enclosure.
• Developed POC for MongoDB database integration into test flow and equipment such as LabView test beds, custom windows software, to demonstrate benefits of centralized data storage and access across R&D test teams, enable dashboarding and automated reporting and documentation on platforms such as Confluence.

Fleet Fuel Testing

Fleet Fuel Testing: Manufacturing Technician

• Manufacturing of test kits for visible clarity, entrained water, and microbial contamination of biofuels.
• Developed fixturing to improve lot size, yield, and reduction of RSI risk.
• Increased efficiency of manufacturing processes through implementation of sub-assembly batch processing and improved organization of material inputs and outputs.