Staff/Principal Mechanical Engineer in Boston

If your idea of a Principal / Staff Mechanical Engineer role is reviewing drawings from a distance and handing requirements to someone else, this probably isn’t for you. This is a hands-on opportunity for a Principal / Staff Mechanical Engineer who wants to stay close to the hardware, solve difficult mechanical problems and take ownership of complex robotic systems from concept through production.

The Opportunity

You’ll join a growing robotics company developing sophisticated autonomous machinery for real-world environments. The engineering challenges sit at the intersection of mechanical engineering, robotics, mechatronics, actuation, sensing and system dynamics. As a Principal / Staff Mechanical Engineer, you’ll play a key role in taking complex electro-mechanical systems from early concepts through detailed design, fabrication, integration, testing and production release. You’ll be working with multi-axis actuation, motors, sensors, mechanisms and large mechanical assemblies, while solving the kinds of problems that don’t always have an answer in a textbook.

Your responsibilities will include:

• Leading the mechanical design and development of complex electro-mechanical and robotic systems
• Designing mechanisms, actuators, tooling and mechanical assemblies for demanding real-world applications
• Taking designs from concept through prototyping, testing, iteration and production
• Performing system dynamics, kinematic analysis, load calculations and vibration analysis
• Developing free-body diagrams and governing equations for complex mechanical systems
• Using simulation, modelling and FEA to validate designs and understand system behaviour
• Specifying motors, actuators, encoders, load cells, proximity sensors and other electro-mechanical components
• Working closely with electrical, controls, software and other engineering disciplines during system integration
• Creating production-ready CAD and engineering documentation
• Contributing to BOMs, part numbering, revision control and other engineering processes
• Supporting fabrication, assembly, debugging and testing of physical systems
• Making engineering decisions where requirements may evolve and the available information isn't always complete

Why This Role?

This is a Principal / Staff Mechanical Engineer position where your technical judgement will genuinely matter. You won't be brought in simply to maintain an existing product. You'll have the opportunity to influence architecture, challenge assumptions, develop new mechanisms and solve problems as the product evolves. The environment is deliberately hands-on. You'll be expected to get involved with the physical hardware, whether that's reviewing a mechanism, analysing a failure, modifying a design, working through system dynamics or getting a prototype ready for testing. You'll also have significant autonomy. The team is small enough that senior engineers can see their decisions move quickly from an engineering discussion into a physical prototype and ultimately into a production system. If you're a Principal / Staff Mechanical Engineer who enjoys complex machinery, robotics and being close to the engineering rather than managing from a distance, this is the kind of environment where your experience can have a disproportionate impact.

What We're Looking For

We're looking for a highly experienced Principal / Staff Mechanical Engineer with a strong background in complex dynamic machines, robotics, automation or similarly sophisticated electro-mechanical products. You'll ideally bring:

• A Bachelor's, Master's or PhD in Mechanical Engineering, Robotics Engineering or a related discipline
• Significant professional experience designing complex electro-mechanical systems
• A track record of taking hardware from concept through product release and production
• Strong mechanical design fundamentals and extensive hands-on engineering experience
• Expertise in system dynamics, modelling, simulation and vibration analysis
• Experience with multi-axis actuation, mechanisms and motion systems
• Experience performing FEA, static/dynamic load calculations and kinematic analysis
• Strong proficiency with SolidWorks
• Experience producing manufacturing-ready engineering drawings and documentation, including GD&T / ASME Y14.5
• Experience working with industrial controls and robotic systems
• A practical, problem-solving mindset and the ability to make sound engineering decisions independently
• Strong communication skills and the ability to collaborate across disciplines

Experience with industrial tooling, engineering documentation systems, MATLAB or Python would also be valuable.

The Environment

You’ll be joining a technically ambitious robotics team where senior engineers are expected to be builders, problem-solvers and technical leaders. The company is working on complex physical systems rather than purely theoretical technology, so you'll see the results of your engineering work in prototypes, test rigs and deployed hardware. For the right Principal / Staff Mechanical Engineer, it's an opportunity to take decades of accumulated mechanical engineering knowledge and apply it to a genuinely new generation of automated systems.

Location: Massachusetts

Working arrangement: On-site

Employment: Full-time

Interested? If you're a Principal / Staff Mechanical Engineer who wants to work on challenging robotic systems, stay hands-on with the hardware and have meaningful ownership over the engineering, we'd like to hear from you.