Actuation Engineer

ABOUT THE ROLE

We are looking for an Actuation Engineer to design, prototype, and productionize the actuators that power our robots. This is a hands-on, cross-disciplinary role: you will own actuator architecture from first principles — picking topologies, sizing motors and gearboxes, selecting transmissions, and validating performance on real hardware — while working closely with controls, mechanical, and firmware teams to make sure the actuator behaves well in the full system, not just on a dyno.

The right candidate has shipped actuators on robots that actually moved in the world, and can articulate why each design decision was made and what was traded off to get there.

RESPONSIBILITIES

• Architect and design rotary and linear actuators for robotic joints, end effectors, and mobility systems.
• Select motors, gearboxes, bearings, sensors, and transmission elements based on quantitative requirements (torque, speed, bandwidth, backlash, stiffness, efficiency, mass, and cost).
• Build motor + gear ratio sizing models that account for duty cycle (when applicable), thermal limits, peak vs. continuous torque, reflected inertia, and the dynamics the actuator is expected to drive.
• Evaluate and choose between transmission types — harmonic drive, planetary, cycloidal, belt/cable, direct-drive, ball/lead screw, and etc. — and clearly justify the tradeoffs for each application.
• Decide between rotary and linear actuation strategies for a given joint or mechanism, including hybrid approaches.
• Partner with controls engineers to ensure actuators meet bandwidth, backdrivability, transparency, and torque-control requirements; iterate on designs when control performance reveals mechanical limitations.
• Specify and integrate sensing — encoders, torque sensors, current sensing, and etc.— and define calibration procedures.
• Design test rigs and run characterization: efficiency maps, thermal soak, backlash, stiction, friction models, lifetime, and failure-mode testing.
• Drive design reviews, DFM/DFA, supplier engagement, and hand-off to manufacturing.
• Debug actuator-related issues found in robot integration, including problems that surface only under closed-loop control or contact-rich tasks.

QUALIFICATIONS

• Demonstrated track record of designing actuators that have shipped or operated on working robots — not just prototypes on a bench. Be ready to walk us through specific designs, the requirements they targeted, and how they performed.
• Deep understanding of the tradeoffs between transmission types (harmonic, planetary, cycloidal, belt/cable, direct-drive), including reliability, efficiency, backlash, stiffness, torque density, backdrivability, noise, lifetime, and cost.
• Clear intuition for when rotary actuation beats linear (and vice versa) — including the implications for envelope, force/torque profiles, mounting, sealing, and control.
• Rigorous approach to motor and gear ratio sizing: ability to start from a robot-level requirement (a payload, a gait, a manipulation task) and end at a defensible motor + gearbox + transmission selection, showing the math along the way.
• Cross-discipline thinking: you understand how mechanical choices show up in the controller — reflected inertia, torque ripple, friction, compliance, sensor placement, and bandwidth — and you design with the control loop in mind.
• Strong fundamentals in mechanical engineering: stress, fatigue, bearings, lubrication, thermal management, and tolerance analysis.
• Proficiency with CAD (CATIA, NX, or similar) and FEA for structural and thermal analysis.
• 5+ years designing actuators for legged robots, humanoids, manipulators, or other dynamic systems.