Position Summary for Senior Mechanical Engineer The Senior Mechanical Engineer leads mechanical design of disposable and consumable components for life-science instruments and medical devices. This role brings deep, hands-on expertise in plastics design, injection molding, and plastics joining/welding for IVD and human-use medical device consumables, along with a strong command of design for user experience, human factors, and bioburden/sterility control. The skill set is intended to support an ongoing portfolio of related development programs (for example, dialysis and other extracorporeal consumables, diagnostic cartridges or cassettes, drug-delivery consumables, and other single-use fluidic or reagent-handling components). The Senior Mechanical Engineer partners closely with chemical, systems, electrical, software, and human factors engineering to integrate fluidic, chemistry, controls, and usability requirements into manufacturable, reliable, and user-friendly consumable designs, while providing technical leadership and credible client interface throughout each program. Key Responsibilities Consumable & Plastics Design • Lead mechanical design of consumable/disposable components (e.g., cartridges, cassettes, fluid-path sets, connectors, filters) for life-science instruments and medical devices. • Apply best-practice plastics design principles (wall thickness, draft angles, ribs/bosses, gate and parting-line placement) to ensure part manufacturability and performance. • Specify and validate plastics joining and welding methods (ultrasonic welding, heat staking, solvent bonding, laser welding) appropriate for fluid-path integrity and biocompatibility. • Evaluate materials for chemical compatibility and biocompatibility, partnering with Quality and Regulatory as needed. • Design sterile barrier packaging systems (e.g., pouches, trays, seals) suited to the target sterilization modality and shelf-life requirements. • Apply design-for-user-experience and human factors principles (IEC 62366) to consumable design, including error-proofing, tactile/visual feedback, and ease of loading for both clinical and home-use operators. • Design consumables for bioburden control and sterility assurance, including material selection and compatibility with sterilization modalities (EtO, gamma, e-beam). • Lead design-for-manufacture (DFM) and design-for-assembly (DFA) reviews with internal manufacturing/operations teams as well as external tooling vendors and contract manufacturing partners, including tolerance stack-up and GD&T analysis. • Lead verification testing of consumables (e.g., burst/leak testing, drop/shock, fatigue, shelf-life) to support design verification and validation. Lead process validation efforts for consumables. • Support pilot builds and design-transfer activities, ensuring consumable designs are robust for high-volume manufacturing. Technical Leadership & Client Interface • Serve as the technical authority on consumables design, manufacturability, and human factors across the program portfolio. • Present mechanical design status, risk assessments, and manufacturability trade-offs at design reviews and client meetings. • Mentor mechanical engineers on plastics design, DFM/DFA for both internal and external manufacturing, and sterility/bioburden best practices. • Represent the mechanical/consumables workstream credibly to clients, balancing innovation, manufacturability, and program constraints. Cross-Functional Collaboration • Partner with process- and materials-focused engineering colleagues to ensure fluid-path materials and geometries meet chemical compatibility, biocompatibility, and performance requirements. • Partner with Systems Engineering to ensure consumable-level requirements are captured, traced, and verified within the system design-control framework. • Coordinate with Quality and Regulatory on biocompatibility (ISO 10993), sterilization validation, and design-history-file documentation. • Collaborate with Operations and Supply Chain on tooling strategy, supplier qualification, and scale-up planning. Qualifications Required • BS in Mechanical Engineering; MS preferred. • 7+ years of mechanical design experience, with significant focus on disposable/consumable components for IVD or human-use medical devices. • Deep, hands-on expertise in plastics design and injection molding, including resin selection, tooling considerations and DFM/DFA practices for both internal and external manufacturing. • Experience with die cutting, coating, converting and associated processes utilized in the production of high-volume consumables. • Direct experience specifying and validating plastics joining/welding methods (ultrasonic welding, heat staking, solvent bonding, or laser welding). • Demonstrated experience applying human factors and user-experience principles to consumable or disposable product design. • Working knowledge of labeling and primary and secondary packaging. • Working knowledge of sterilization modalities, bioburden control, and sterile packaging design for medical device consumables. • Proficiency with GD&T, tolerance stack-up analysis, and CAD tools (e.g., SolidWorks). • Strong leadership and written/verbal communication skills, with demonstrated ability to lead technically and interface credibly with clients. Preferred • Experience with fluid-path or wetted consumable design (e.g., cartridges, tubing sets, filters) in dialysis, infusion/IV therapy, diagnostics, or similar applications. • Familiarity with ISO 10993 biocompatibility testing and sterilization validation (ISO 11135, ISO 11137). • Experience designing consumables for home-use or lay-user environments. • Proficiency with AI tools. • Patent experience in consumable or disposable medical device design. This role is onsite in San Diego. Salary range: $150,000-$185,000 plus benefits, PTO and 401k with matching