We're looking for a Senior Mechanical Engineer to own the neck of our humanoid robot platform. You'll own actuation selection and packaging for the neck's degrees of freedom, drive the head stabilization strategy with controls engineers, define the mass and CG budget the head team designs to, and coordinate the interfaces to torso, head, and cladding. This is a high-ownership role where actuator engineering, dynamics, and packaging craft come together in one of the most expressive parts of the robot. **What You'll Do** - Own the mechanical architecture of the neck - kinematics, joint arrangement, structural design, and packaging of the full mechanism within a slender, ID-constrained envelope - Lead actuation selection and packaging for the neck's degrees of freedom - evaluating motor, gearbox, and transmission options against torque, bandwidth, backdrivability, acoustic, and packaging requirements - Define the head mass and center-of-gravity budget in partnership with the head team, and own the system-level trade between head mass, neck actuator sizing, and dynamic performance - Develop and validate the head stabilization strategy in collaboration with controls engineers - structural stiffness, backlash and compliance management, vibration isolation, and the dynamic performance needed for stable imagery from head-mounted cameras - Design for quiet, smooth, lifelike motion - managing gear noise, cogging, and structural resonances in a subsystem that operates close to people's faces - Define and own the mechanical interface to the head - structural mount, alignment and registration, electrical pass-through, and serviceability - and the interface to the torso below, driving both to closure with their respective teams - Own cable routing through the neck: power and data runs to the head across moving joints, service loops, strain relief, and bend-cycle durability through the full range of motion - Work closely with the cladding team on the moving-surface problem - gaps, pinch points, flexible or telescoping cladding elements, and attachment schemes that survive continuous articulation - Create and maintain CAD models, drawings, tolerance stacks, and BOMs to support design reviews, prototyping, and manufacturing handoffs - Plan and execute prototype builds and test campaigns - dynamic performance, acoustics, durability, and stabilization - and lead root cause analysis when issues arise **What We're Looking For** - BS in Mechanical Engineering or a closely related field (MS preferred) - 5+ years of experience in mechanical design of actuated mechanisms - robotics, gimbals, precision motion systems, or similar - Demonstrated experience selecting and integrating actuators - motors, gearboxes, and transmissions - including sizing against dynamic requirements and packaging into tight envelopes - Strong command of mechanism design fundamentals: kinematics, stiffness, backlash, preload, and bearing selection for precision motion - Hands-on experience with cable routing and harness design across articulating joints - Expert-level proficiency with CAD software (Catia, SolidWorks, Fusion 360, Onshape, or similar) for complex part and assembly design - Deep familiarity with manufacturing processes - machining, casting, injection molding, sheet metal, 3D printing - and design-for-manufacture principles - Comfort working hands-on with hardware: building prototypes, running tests, and troubleshooting physical systems - Strong communication skills and the ability to drive requirements to closure across mechanical, electrical, controls, and design disciplines **Nice to Have (But Not Required)** - Experience designing gimbals, camera stabilization platforms, or pan-tilt mechanisms with image-stability requirements - Experience with humanoid robots, animatronics, or other systems where expressive, lifelike motion matters alongside function - Background in acoustic and NVH design for mechanisms - gear noise, motor noise, and structural resonance mitigation - Experience partnering with controls engineers on servo performance, system identification, or stabilization tuning - Familiarity with harmonic drives, cycloidal reducers, or other compact precision transmissions - Working knowledge of GD&T (ASME Y14.5) applied to precision motion assemblies - Experience taking a subsystem from concept through DVT/PVT into production **Why This Role** - Own a complete precision motion subsystem - actuation, structure, cabling, and stabilization, end to end, in a package where every millimeter and every gram is contested - Make the robot feel alive - the neck is where smooth, quiet, expressive motion happens, and your engineering directly shapes how the robot reads to the people around it - Join at a foundational moment and make architecture-level decisions on one of the most dynamically demanding subsystems of a next-generation humanoid robot