Senior Mechanical Engineer

XII Medical, Inc.; Union City (CA); On-site; USD 120,000 - 190,000; Full time

Job summary

XII Medical, Inc. is seeking a Senior Mechanical Engineer to lead the design, development, and validation of mechanical components for durable medical equipment used at home.

You will own subsystems from concept through commercialization, collaborating with R&D, electrical/firmware, and manufacturing to ensure performance, safety, and regulatory compliance. The role requires strong mechanical fundamentals, hands-on problem solving, and the ability to thrive in a fast-paced startup environment.

Qualifications

• Strong understanding of mechanical engineering fundamentals and product development processes.
• Experience with durable medical equipment (DME) development and design controls.
• Hands-on prototyping, testing, and troubleshooting of electromechanical systems.

Responsibilities

• Lead mechanical design of components, enclosures, and systems for DME.
• Own design control deliverables and traceability from concept to sustaining engineering.
• Collaborate with R&D, Electrical/Firmware, Quality, Regulatory, and Manufacturing.
• Perform analyses (tolerance stack-ups, FEA, thermal) to support decisions.
• Develop prototypes, validate designs, and iterate based on test data.

Skills

Prototyping

Diagnostics

Cross-functional

Regulatory awareness

Education

Bachelor’s degree in Mechanical Engineering

Tools

SolidWorks

GD&T (ASME Y14.5)

FEA

Minitab

Job description

XII Medical is a clinical-stage medical technology company on a mission to develop and commercialize best-in-class sleep apnea therapies that simplify treatment, expand access, and improve patient outcomes. A seasoned leadership team, world-class board of directors, and a strong investor syndicate position XII Medical to achieve that mission and meaningfully improve the quality of life of sleep apnea patients and their families. XII Medical offers competitive compensation and benefits and a vibrant culture built on its core values.

Position Summary

The Senior Mechanical Engineer is responsible for leading the design, development, and validation of mechanical components and systems for durable medical equipment (DME)—reusable mechanical and electromechanical devices used in home. This individual will own mechanical subsystems across the full product lifecycle—from early concept and prototyping through design verification, validation, design transfer, commercialization, and sustaining engineering.

This role requires strong engineering fundamentals, hands-on problem-solving, sound technical judgment, and the ability to lead in a fast-paced, start-up environment.

The Senior Mechanical Engineer will collaborate cross-functionally with R&D, Electrical/Firmware, Human Factors, Manufacturing, Quality, Regulatory, and external partners to ensure designs meet performance, safety, reliability, and regulatory requirements in compliance with the FDA Quality Management System Regulation (21 CFR Part 820), ISO 13485:2016, ISO 14971, and applicable product standards.

Mechanical Design & Development

• Lead the design and development of mechanical components, assemblies, and systems for durable medical equipment, including enclosures and patient-contact surfaces
• Design enclosures for EMC and thermal management
• Generate and maintain 3D CAD models, engineering drawings (applying GD&T per ASME Y14.5), and design documentation
• Perform and review engineering analyses (e.g., tolerance stack-up, hand calculations, FEA, stress/strain, thermal, fatigue) to support design decisions and demonstrate design margin
• Develop prototypes and iterate designs based on testing, user feedback, and field data
• Design for the full DME use environment, including repeated cleaning and disinfection, transport and handling, foreseeable misuse and abuse loads, and multi-year service life
• Select materials (e.g., metals, engineering plastics, elastomers, foams, textiles) considering strength, durability, chemical compatibility with cleaning agents, flammability, and biocompatibility (ISO 10993) for patient-contacting surfaces
• Design enclosures and chassis for electromagnetic compatibility (EMC) in partnership with Electrical Engineering, including shielding strategy, seam and aperture control, conductive gaskets and coatings, grounding and bonding paths, and cable routing
• Own thermal management of electromechanical assemblies, including heat-sinking, natural and forced-convection airflow, and venting balanced against ingress protection, supported by hand calculations and thermal/CFD simulation

Product Development & Design Controls

• Lead mechanical development through all phases of product development, from concept through design transfer, commercialization, and sustaining engineering
• Own design control deliverables for assigned subsystems, including design inputs, outputs, verification, validation, and design reviews
• Ensure traceability between user needs, design requirements, risk controls, and test results
• Lead risk management activities for mechanical subsystems (e.g., DFMEA, hazard analysis) per ISO 14971, and implement and verify risk control measures
• Support human factors/usability engineering (IEC 62366-1) as it relates to mechanical interfaces, controls, ergonomics, and patient and caregiver handling

Testing & Validation

• Define test strategy and develop and execute design verification and validation (V&V) test protocols, including test method development and validation
• Support EMC pre-compliance and certification testing (emissions, immunity, ESD) and thermal characterization (thermocouple and IR mapping, worst-case ambient and duty cycle), and drive mechanical design fixes for any failures
• Analyze test data using appropriate statistical methods (e.g., confidence/reliability-based sample sizes) and document results in formal reports
• Lead failure investigations and root cause analysis for design-related issues

Cross-Functional Collaboration

• Partner with Manufacturing Engineering to ensure design for manufacturability (DFM) and design for assembly (DFA), and lead design transfer to production
• Collaborate with Quality and Regulatory teams to ensure compliance with applicable standards and requirements, and support regulatory submissions (e.g., 510(k)) and third-party safety testing
• Work with suppliers and contract manufacturers to support component development, material selection, and process capabilities (e.g., injection molding, sheet metal, machining, welding, extrusion, foam and textile fabrication)
• Mentor and provide technical guidance to junior engineers and technicians, including review of designs, analyses, and documentation

Documentation & Compliance

• Create and maintain comprehensive engineering documentation in accordance with internal procedures and regulatory requirements
• Author and maintain design history file (DHF) content, and support device master record (DMR) development and engineering change orders (ECOs)
• Ensure compliance with FDA, ISO, and internal quality system requirements
• Identify opportunities to improve product performance, reliability, serviceability, and cost, including value engineering of existing products
• Contribute to innovation efforts, including concept generation and feasibility assessments
• Stay current with new materials, technologies, and design methodologies relevant to medical device development

Qualification Requirements:

• Strong understanding of mechanical engineering fundamentals and product development processes
• Advanced proficiency with 3D CAD (e.g., SolidWorks or similar)
• Working knowledge of GD&T (ASME Y14.5) and tolerance analysis
• Experience with FEA and statistical tools (e.g., Minitab); DOE experience a plus
• Experience designing enclosures for EMC (shielding, gasketing, grounding) and thermal management (heat-sinking, airflow, thermal simulation) of electromechanical products
• Demonstrated experience working under design controls in a regulated product development environment (FDA 21 CFR Part 820, ISO 13485, ISO 14971)
• Experience designing durable, reusable mechanical and electromechanical products for demanding use environments
• Familiarity with DME-relevant standards (e.g., IEC 60601-1 and applicable particular standards) and experience working with third-party test labs
• Hands-on experience with prototyping, testing, and troubleshooting mechanical systems
• Strong analytical and problem-solving skills
• Excellent communication and collaboration skills in cross-functional teams
• Ability to manage multiple priorities and lead technical workstreams in a fast-paced, start-up environment

Education & Experience Requirements

• Bachelor’s degree in Mechanical Engineering or related field required
• 7+ years of mechanical product development experience (or 5+ years with a Master’s degree), including 3+ years in medical devices
• Durable medical equipment or comparable electromechanical medical product experience strongly preferred
• Sleep industry or wearables experience preferred
• Demonstrated track record of taking at least one product from concept through commercial launch

Travel Requirement

• Ability to travel domestically and/or internationally as needed
• Primarily onsite at the company’s facility, with occasional offsite work for testing, vendor visits, or with manager approval