Mechanical Design Engineer II - Reactivity Controls

About Us

At Antares, our long-term mission is to make clean energy abundant from Earth to the Asteroid Belt. We’re fueled by the belief that advanced nuclear energy can strengthen our military, solve the climate crisis, elevate global living standards, and expand humanity's presence in outer space. To achieve our mission, we’re building mass-producible, inherently safe, deployable microreactors that can be used terrestrially, underwater, and in space.

The Antares team hails from SpaceX, the White House, the Pentagon, the Department of Energy, MIT, Rigetti Computing, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Idaho, Oak Ridge, Los Alamos, and Savannah River. Antares has raised over $600M in venture capital from top-tier investors and has hundreds of million-dollars on contract with the military services, NASA, and the Department of Energy.

As the Responsible Engineer for Reactivity Controls – Mechanical, you will lead the design, development, testing, and validation of the mechanical systems that govern reactor reactivity and ensure the safe operation of the reactor. You will architect and build the mechanical mechanisms that interface with electrical and software subsystems, collaborating closely across disciplines to define system architecture, requirements, and documentation.

The ideal candidate has a strong track record in designing and developing precision control mechanisms, preferably with experience in robotics or electromechanical systems. You will also contribute to system-level architecture trade studies and support the evaluation and selection of key vendors.

• Design, build, and test the reactor’s control mechanisms, hardware and assemblies.
• Concept and develop custom actuation solutions, including mechanisms, linkages, interfaces, and instrumentation.
• Define design criteria, requirements, system architecture, and verification/validation test plans.
• Collaborate closely with cross-functional teams across thermal, structural, neutronics, controls, and simulation disciplines.
• Engineer components for high-temperature, high-stress, and radiation environments using metals, ceramics, and other advanced materials.
• Perform design-for-manufacturability (DFM) assessments and execute tradeoffs across performance, cost, schedule, and risk.
• Conduct mechanism trade studies, document findings, and present recommendations to senior leadership

• Bachelor's degree in engineering
• 3+ years of experience in a full-cycle design engineering roles, encompassing hands-on experience with CAD, analysis, build and test
• Experience with kinematic synthesis, pneumatic/hydraulic actuation, mechatronics and instrumentation
• Experience with FMEA including structure strength, stability and fatigue failure modes

• Master's degree in engineering
• 1+ years of experience in a full-cycle design engineering roles, encompassing hands-on experience with CAD, analysis, build and test
• Experience in the Nuclear, Aerospace, or Robotics industries
• Experience in a demanding fast-paced development environment
• Experience with design engineering tools such as NX, ANSYS or Femap, and other product lifecycle software
• Experience with engineering scripting languages such as Python and MATLAB

• Ability to work long hours and weekends as necessary to support critical milestones

• We are located in Torrance, CA in a 145,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our facility is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and…