Radiant
Nuclear Energy
SeniorMechanismsEngineer
Neural analysis suggests this role is
optimal for Senior candidates.
“Senior Mechanisms Engineer at Radiant. Skills: Mechanisms design, Stress analysis, FEA. Design critical mechanisms. Conduct trade studies”
What You'll Achieve.
Fuel first commercial reactor design by 2026
Industry & Context.
Solve unique challenges
Work extended hours, Work weekends, 100% onsite, U.S. export controls compliance
What They're Looking For.
Must Have
Bachelor's degree in Mechanical or Aeronautical Engineering, 4+ years of experience designing mechanisms, 4+ years performing stress analysis, 4+ years using hand calculations and FE tools
Nice to Have
Experience with CAD design, Experience designing manufactured hardware, Experience designing pneumatic systems, Experience integrating electromechanical components, Experience working with interdisciplinary teams, Solid understanding and application of GD&T, Proficiency with analytical methods, Proficiency with finite element-based analysis, Ability to derive free-body diagrams, Experience with text-based software development tools
What You'll Do.
Design critical mechanisms
Conduct trade studies
Perform thermomechanical analysis
Perform kinematic analysis
Develop manufacturing instructions
Develop assembly instructions
Create Bill-Of-Materials
Manage Bill-Of-Materials
Own subassembly design
Own subassembly manufacturing
Own subassembly test schedules
How You'll Work.
Team & Collaboration
Interdisciplinary teams; Engineers in other functional areas
Communication Scope
Clear communication; Constructive communication
Process & Methodology
Schedule management
Full Job Description
ABOUT RADIANT Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028. ABOUT THE ROLE Radiant is seeking a highly motivated Senior Mechanisms Engineer to design and develop critical mechanisms within Kaleidos. You will solve unique challenges creating efficient and reliable mechanisms that control reactivity or actuate critical safety features. You will be responsible for the following: trade studies, material selection, detailed structural analysis, assembly, integration, and testing. You will have an instrumental impact of fueling the first new commercial reactor design in over 50 years by 2026. Responsibilities & Duties: - Ownership of critical mechanisms such as the control blade actuator or air jacket valves. - Conduct trade studies and develop designs to meet program requirements. - Perform detailed thermomechanical analysis (static strength, durability/fatigue) and kinematic analysis to determine structural integrity and performance margins using both hand calculations and finite element tools. - Develop and execute manufacturing/assembly instructions and test plans. - Create and manage a Bill-Of-Materials (BOM). - Find and develop suppliers for components. - Own subassembly design, m
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