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Senior Mechanical Design Engineer - Reactivity Controls

Antares
Los Angeles, United Statesfull_timeVerifiedPosted 2 Dec 2025
💰 $185,000/yr($140,000/yr$185,000/yr)

About the role

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.

Formed in 2023, the Antares team hails from SpaceX, The White House, MIT, Rigetti Computing, The Air Force, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Los Alamos, Idaho, and Oak Ridge. Antares has raised over $130M in venture capital from top-tier investors and has over $13M in government funding.

About the Role

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.

Roles and Responsibilities:

  • 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

Basic Qualifications:

  • Bachelor's degree in engineering

  • 5+ 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

Preferred Skills & Experience:

  • Master's degree in engineering

  • 7+ 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

Additional Requirements:

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

Location

  • 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 enterprises.

Culture

At Antares, we like to specifically tie each role to our founding document’s set of values–here are the top five cultural values we think you should believe at your core to be successful:

  • Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities, conflicting policies, perverse incentives, and emergent and path-dependent properties. First principles thinking alone is insufficient. Think probabilistically and then take action. “If you want to be certain, then you are apt to be obsolete.” Over-optimizing the components of

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Company

Antares

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