Senior Member of Technical Staff: Mechanical Engineering — Actuation

About the role

We are hiring a Senior Mechanical Engineer to design, build, and ship high-performance actuators for our humanoid robot. In this role, you will own the design of actuator mechanical components and subassemblies, working closely with controls, electrical, firmware, and manufacturing teams to translate performance requirements into robust hardware and mature prototypes into reliable, high-volume production designs. This role is ideal for an engineer who thrives owning a design end-to-end, from first-principles analysis through hands-on bring-up, characterization, and production handoff.

Responsibilities

• Design and deliver actuator mechanical subsystems, including gear trains and transmissions, housings, bearing arrangements, shafting, output interfaces, and integrated sensor and motor packaging.
• Drive component sizing and validation through first-principles analysis and FEA—tolerance stack-ups, structural and fatigue analysis, stiffness, backlash, and thermal paths.
• Own designs from concept through DFM/DFA, prototype builds, and production release, partnering with external manufacturers and suppliers to ensure high-quality parts and assembly.
• Partner cross-functionally with controls, electrical, and firmware teams to define actuator requirements and integrate actuators into the broader robot platform.
• Lead design reviews and hardware bring-up; plan and execute bench and dynamometer testing to characterize performance and root-cause failures.
• Establish design standards and best practices for actuator development, and mentor engineers across the team.

Requirements

• 5+ years of experience delivering precision electromechanical or actuator products from concept through production (or MS + 3 years).
• Deep expertise in actuator and drivetrain design, including gear trains (planetary, harmonic, and/or cycloidal), bearing selection and preload, shaft and housing design, and management of backlash and stiffness.
• Strong proficiency with 3D CAD (SolidWorks, CATIA, or NX) and rigorous application of GD&T and tolerance analysis.
• Demonstrated analytical ability using both hand calculations and FEA for structural, fatigue, and thermal design decisions.
• Hands-on experience building, instrumenting, and testing hardware, including dynamometer or bench characterization and systematic troubleshooting.
• Strong communication, ownership, and a collaborative, cross-functional approach to development.

Preferred Qualifications

• Direct experience with robotic systems, preferably humanoid and/or manipulation robots.
• Experience designing high-torque-density actuators with frameless/BLDC motor integration.
• Experience with custom gearbox design (planetary and harmonic or cycloidal drives), experience with gear analysis tools such as KISSsoft or similar software, and high-volume manufacturing of precision mechanical components.

Benefits

• Competitive total compensation program, including salary, annual cash bonus, and company equity.
• Company-subsidized insurance programs.
• 401(k) with company match.
• Flexible PTO.
• Daily lunch.