Principal Mechanical Engineer

Role Overview

• Lead the mechanical design of major robotic platforms across the full product lifecycle, from concept and prototyping through NPI and sustained field deployment.
• Set the technical direction for how the Robot platforms are architected, packaged, and manufactured; make system-level decisions that hold up through production and deployment, not just during design review.
• Define design requirements, perform tolerance stack-ups, and drive interface decisions across complex assemblies integrating actuators, sensors, and electronics.
• Ensure structural integrity of mechanical assemblies: define load cases, run or direct finite element analysis (FEA), select materials, and validate through physical test.
• Conduct simulations, testing, and prototyping to validate designs.
• Create detailed technical drawings, CAD models, and documentation.
• Troubleshoot and resolve issues during design, production, and deployment.
• Drive design solutions through sketches and CAD, gather cross-functional input early, and build alignment across stakeholders before committing to a direction.
• Ensure compliance with industry standards, safety regulations, and quality control processes.
• Support production teams in scaling and improving manufacturing processes for robotics hardware.
• Serve as a technical anchor for the mechanical engineering team, setting the bar for design rigor, documentation quality, and engineering judgment.
• Mentor and develop junior and mid-level engineers through design reviews, hands-on guidance, DFM coaching, and best-practice modeling.
• Lead and participate in cross-functional design reviews, identifying risks early and driving alignment across hardware, software, and manufacturing stakeholders.
• Lead continuous improvement efforts in robot performance and reliability.

Requirements

• A bachelor’s or master's degree in Mechanical Engineering or a related field.
• A Mechanical Engineer with 10+ years of experience, ideally in robotics, automation, consumer electronics, aerospace, or EV, with a strong structural design background and a track record of technical ownership at the system level.
• FEA experience that goes beyond the resume line. Has worked through real structural problems. The candidate should be able to set up their own analyses, sanity-check results with hand calculations, and close the loop with physical test data rather than trusting the model.
• Must have experience designing machined, sheet metal, and welded parts in OnShape and submitting documentation through ECO’s and deviations in Arena or other similar tools.
• Comfortable ordering and building prototypes by hand to validate their ideas through prototyping and testing.
• Must have performed tolerance stackups, reviewed FAI’s, PPAP’s, and worked on DFMEA’s throughout their career.
• Has followed designs through the production line, diagnosing and fixing issues in engineering or production builds, as well as in the field.
• Strong engineering judgment across both design and hands-on execution, with the ability to move between CAD, simulation, building, testing, and debugging real hardware.
• Adept at communicating complex concepts and writing technical documents.
• Experience evaluating design, performance, and logistical tradeoffs for hardware systems.
• Experienced in designing for a range of manufacturing processes, including CNC machining, sheet metal fabrication, welding, and 3D printing.
• Able to work in a fast-paced, collaborative environment.
• Comfortable thinking at the product level, seeing how mechanical subsystems connect, package, and are manufactured together, and can make system-level architecture calls that hold up through production and deployment, not just through the design review.
• Experience mentoring or technically guiding junior and mid-level engineers on design reviews, DFM, and best practices.
• Willing and able to work from our Charlestown, MA office at least 4 days per week.

Benefits

• health, dental, & vision insurance
• unlimited vacation, along with all federal and state holidays
• 401K contributions of 5% your salary
• travel supplies
• other items to make your working life more fun, comfortable, and productive