Mechanical Engineer - Legs Tech Lead

Apptronik is a human-centered robotics company developing AI-powered robots to support humanity in every facet of life. Our flagship humanoid robot, Apollo, is built to collaborate thoughtfully with people, starting with critical industries such as manufacturing and logistics, with future applications in healthcare, the home, and beyond.

We operate at the cutting edge of embodied AI, applying our expertise across the full robotics stack to solve some of society's most important problems. You will join a team dedicated to bringing Apollo to market at scale, tackling the complex challenges like safety, commercialization, and mass production to change the world for the better.

Apptronik is seeking a Staff Mechanical Engineer to serve as the technical lead for Apollo’s lower body. This is a high-visibility leadership role responsible for the hip, leg, knee, ankle, and foot assemblies.

You will own the complete lifecycle—architecture, design, integration, and verification—of the lower body stack. This position requires deep expertise in locomotion kinematics, dynamic stability, and high-load structural design. You will lead the development of systems that must deliver human-like mobility, absorb high-energy impacts, and maintain durability across millions of cycles in real-world environments.

• Lower Body Ownership: Define the mechanical architecture for the hips, legs, knees, ankles, and feet. Lead trade-off studies between power density, range of motion (ROM), stability, and energy efficiency.
• Locomotion Performance: Architect systems that enable stable walking, running, lifting, and recovery from disturbances (e.g., slips, trips, and falls). Balance dynamic performance with robustness and safety.
• Mass Distribution & Stability: Optimize mass placement and inertia to improve balance, agility, and whole-body coordination.

• High-Performance Joints: Drive the design of multi-DOF joints (hip, knee, ankle) capable of high torque output and high cycle life while maintaining precision and backdrivability where needed.
• Shock & Impact Management: Design structures and mechanisms that absorb and dissipate energy during foot-ground contact and high-impact events (e.g., stepping off ledges, falls).
• Structural Integrity: Lead the design of the lower body load path to support full robot mass and dynamic loads using advanced materials and topology optimization.

• Foot & Contact Design: Develop feet and contact interfaces that provide traction, compliance, and adaptability across varied terrains.
• Actuation Integration: Partner closely with controls and actuation teams to ensure mechanical designs support force control, impedance control, and dynamic motion planning.

• Subsystem Integration: Lead integration of actuators, sensors, and structural elements within tight mechanical envelopes.
• Cable & Harness Routing: Architect robust routing strategies through high-flex joints (hips, knees, ankles), ensuring multi-million cycle reliability and maintainability.
• Environmental Robustness: Ensure designs meet requirements for ingress protection (IP), thermal performance, and durability in real-world operating conditions.

• DVT Ownership: Define and execute the Design Verification Test (DVT) plan for the lower body, including fatigue testing, impact testing, and long-duration lifecycle validation.
• Failure Analysis: Lead root cause investigations for field or lab failures related to wear, fatigue, or performance degradation.
• Technical Mentorship: Conduct deep-dive design reviews, establish best practices for dynamic robotic systems, and mentor engineers across experience levels.

• Experience: B.S. in Mechanical Engineering with a 8+ years of experience in mechanical design of complex robotic systems, with a focus on legged systems or high-load dynamic mechanisms.
• Drive Through Influence: Proven ability to lead technical initiatives and align cross-functional stakeholders without direct authority. Strong track record of driving system-level decisions.
• Su…