Mechanical Engineer

Mechanical EngineerPersona AI is building humanoid robots for the most demanding environments in heavy industry — shipyards, steel mills, fabrication facilities, and offshore platforms — performing welding, grinding, maintenance, inspection, and material-handling work that is dangerous, physically demanding, and increasingly difficult to staff.We are backed by leading strategic and financial investors and engaged with global industrial leaders across Korea, Japan, the United States, and Singapore. Korea is the center of gravity for our early commercial strategy, anchored by relationships with the world's leading shipbuilders and steelmakers. Our work spans both the robot platform itself and the systems, partners, and playbooks required to deploy it at scale.Why Join Persona AI?We offer competitive compensation, a performance-based bonus, 99% employer covered medical benefits, early-stage equity, competitive PTO, and a company-wide paid winter break between December 24th and January 2nd.You'll shape technology that's redefining the possibilities of robotics and human interaction.Work alongside passionate teammates who value creativity, and continuous learning.About the RoleAs an early Mechanical Engineer at Persona, you will help shape the design of Persona's humanoid robots while helping set the engineering culture of the company. We're looking for exceptional people who dream big, thrive on challenges, and love seeing their designs come to life — from initial sketches through CAD modeling, prototyping, manufacturing, testing, and deployment on real industrial job sites.We are primarily interested in candidates who have shipped products in the fields of autonomy, robotics, consumer products, medical devices, automotive, or aerospace.What You Will Be DoingCreate and refine mechanical designs for advanced humanoid robotics, including actuators, manipulators, and integrated systems.Own your designs from initial sketches through CAD modeling, prototyping, manufacturing, testing, and deployment.Conduct simulations, structural analysis, and performance evaluations to optimize system functionality.Generate comprehensive documentation, including CAD drawings, block diagrams, test plans, fabrication, and assembly instructions.Interface with external manufacturing partners to optimize designs for manufacturing, testing, and assembly.Engage hands-on in the lab, transforming your designs from ideas to production systems through rapid, iterative development cycles.Collaborate closely with cross-functional teammates (electrical, software, controls, UX/UI, and industrial designers) to ensure seamless integration across the product.Solve fascinating engineering challenges daily, pushing the boundaries of robotics technology.What We Are Looking For:Bachelor's, Master's, or PhD degree in Mechanical Engineering, Manufacturing, Robotics, Biomechatronics, Mechatronics, or related fields.5+ years of experience (3+ years with advanced degree) designing mechanical systems in consumer products, robotics, aerospace, medical, automotive, or similar fields.Proven track record shipping products to market, ideally at scale.Experience designing for high-volume mass manufacturing DFM processes such as injection molding, sheet metal, stamping, casting, composites, or CNC machining.Practical hands-on experience with prototyping tools, manufacturing techniques, and material selection.Proficient CAD user (Onshape, SolidWorks, Catia, Creo, Fusion, etc.) with a passion for precise, elegant, scalable design.Strong grasp of mechanical engineering fundamentals.Strong analytical and problem-solving skills with the tenacity to tackle complex challenges, comfortable performing detailed engineering analyses (FEA, hand calculations, etc.).A friendly, collaborative mindset, strong communication skills, and excitement to work hands-on in a dynamic, supportive team environment; design without ego.Working understanding of tolerance analysis and GD&T.Keen attention to detail and craftsmanship, including fit and finish.Bonus Skills:Hands-on experience with humanoid robotics, exoskeletons, or other articulated mechanical systems.Enjoys detailed design of complex surface geometry.Experience designing precision mechanisms, actuators, tight tolerance components.Familiarity with motors, actuators, transmissions (planetary, cycloidal, strain-wave), bearings, or cable drives.Experience designing cable harnesses, wire routing, or flexible PCBs.Ability to analyze thermal systems (hand calculations or FEA).Proficiency in C, Python, MATLAB, or similar analytical tools.Familiarity with classical or modern controls.Preference toward working in interdisciplinary, fast-paced environments.Experience collaborating with industrial designers, human factors, or UX/UI teams.Skilled at complex surface geometry and tight packaging constraints in CAD.Comfortable working in a machine shop (mill, lathe, etc.).Persona AI is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, sexual orientation, gender identity, age, disability, veteran status, or any other characteristic protected by applicable federal, state, or local law.