Mechanical Design Engineer - Robot Parts & Enclosures (Contract)

About OS3

Affordable, intelligent humanoid robots built to deploy at scale

Tech

We build the full stack of general-purpose robotics: custom robot hardware and the AI that runs it. Owning both sides gives us a complete data flywheel — our robots collect data in the real world, that data trains our models, and improved models go back on the robots within days. Our engineering work spans: - Training VLAs and world models - Simulation-based training to reduce the need for real robot data - Reinforcement learning from real-world robot rollouts, improving policies beyond what imitation alone can reach - Physics simulation with sim-to-real evaluation gates, and GPU inference infrastructure serving policies to robots in real time - Real-time control software, teleoperation-based data collection, and safety systems - Custom mechanical design for CNC, sheet metal, and 3D printing, along with custom electronics

The role

We design and build our robots in-house, from structural parts to exterior covers, and iterate on them continuously as the robots run in the real world. You'll own the CAD design of robot parts and enclosures — working remotely, with your designs printed, machined, and tested on real robots in our San Francisco lab.**You will:*** Design robot parts, enclosures, and covers in CAD for 3D printing, CNC, and sheet metal* Package cameras, sensors, compute, actuators, and wiring into clean, serviceable assemblies* Own designs from concept through prototype, assembly feedback, and revision* Produce CAD geometry clean enough to feed our simulation and testing pipeline* Iterate fast: you design remotely, we build in SF, and you get feedback from real robots within days**You have:*** Strong CAD fundamentals — parametric modeling, assemblies, tolerancing, DFM* Hands-on prototyping experience: you've printed, machined, assembled, and fixed your own designs* A feel for designing around electronics, cabling, and moving joints* Clear async communication — you can drive a design loop remotely* **Nice to have:*** Experience with robot arms, grippers, or mobile platforms* Industrial design sensibility for exterior covers and finishes* Option to convert to full-time. In-person interns are welcome to apply as well, provided they have CAD experience.

Skills

• CAD Design