Senior Hardware-in-the-Loop (HIL) Engineer

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El Segundo, CA
In-Office
Greentech • Hardware • Energy
The nuclear power people want.
The Role

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 failsafe microreactor that can be transported anywhere power is needed and run for up to five years without the need to refuel. 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 utilizes modern software engineering to rapidly achieve safe, factory-built microreactors that leverage existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor next year at the Idaho National Laboratory, with initial customer deliveries beginning in 2028.

Senior Hardware-in-the-Loop (HIL) Engineer  

Radiant is seeking a Senior Hardware-in-the-Loop (HIL) Engineer to own and develop Radiant’s NI PXI-Based HIL system for Kaleidos. You will be responsible for the end-to-end development from requirements gathering, hardware sourcing and development, integrating HIL into our software systems, and completing through commission.  

The ideal candidate will have extensive experience with NI PXI hardware, real-time testing, and automated validation frameworks. 

You will also own harnessing design from an early stage, component selection, qualification through production. The ideal candidate is comfortable working both autonomously and with an interdisciplinary team, as well as in the early design architecture phases of development.  

You will have the opportunity to build electrical integration systems from the ground up that will drive success towards the first successful fuel demonstration of a new commercial nuclear reactor design in over 50 years.

Responsibilities and Duties:   

  • Design, develop, and maintain a hardware-in-the-loop (HIL) test bench system. 
  • Build and configure test hardware, including power supplies, actuators modeling, sensor mapping. 
  • Establish communication with Digital Twin and program required interfaces. 
  • Own schedule, budget, vendor management, and assembly of harness and HIL systems. 
  • Optimize validation process, build and work with robot tool to run the test. 
  • Support and aid in test development for other critical systems. 
  • Develop and document test procedures, methodologies, and best practices effectively. 
  • Troubleshoot issues that arise in relation to electrical integration of test stands and Kaleidos hardware. 
  • Present design reviews and gather input from cross-functional teams. 

Required Skills and Qualifications: 

  • BS in Electrical Engineering, Computer Engineering, or similar discipline from an accredited institution.  
  • Experience with HIL systems such as dSpace, NI PXI, Speedgoat or similar platforms. 
  • 5+ years developing hardware in the loop test systems.  
  • Proficient in NI HIL Software (e.g. Labview, TestStand) as well as Python, C++ or C# (minimum scripting level). 
  • Hands-on experience with data acquisition and test execution.  
  • Electrical debugging and root cause analysis.  
  • Demonstrated ability to work independently and in a team environment.
  • Experience working cross-functionally. 

Desired Skills and Qualifications: 

  • Run tests at HW-SW integration level (HIL), document and report test results. 
  • Practical knowledge of the fundamental concepts of controls, software testing, and test processes. 
  • Hands-on skills to design, build, bring up, and debug test benches. 
  • Experience with 'Real Time' simulation systems and/or FPGA-based systems. 
  • Familiarity using trace capture tools, data acquisition, and analysis tools such as Nominal. 

Additional Requirements

  • Must be willing to work extended hours and weekends as necessary to accomplish our mission.
  • Must work 100% onsite at El Segundo HQ.

Total Compensation and Benefits

Radiant's new hire compensation package includes base salary, substantial equity grants, and comprehensive benefits. Total compensation and level are determined through a holistic evaluation of your interview performance, experience, education, and qualifications. 

Benefits and Perks for Eligible Employees:

  • Stock: Substantial incentive stock plan for all full-time employees.
  • Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.
  • One Medical: Sponsored memberships for employees and their dependents.
  • Vision: 100% top tier plan coverage + 50% for dependents.
  • Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.
  • Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.
  • 8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.
  • Daily catered lunch. Free snacks and drinks.
  • Flexible PTO policy. Remote workday allocation.
  • Company and team-bonding events, happy hours and in-person camaraderie.
  • Beautiful El Segundo headquarters close to the Pacific Ocean.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time.

This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.

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The Company
HQ: El Segundo, CA
40 Employees
Year Founded: 2019

What We Do

Radiant is a clean energy startup building a nuclear microreactor. A climate-friendly alternative to diesel generators, Radiant's Kaleidos 1MW microreactor will be the world's first portable, zero-emissions power source that works anywhere. We plan to test our development reactor by 2026 and if successful, it will be the first new commercial reactor design to achieve a fueled test in over 50 years. Our microreactor can bring power to remote parts of the world and provide backup power for life-saving applications in hospitals or disaster-relief scenarios.

Why Work With Us

Our world-class team has prior experience in complex hardware development from SpaceX, McMaster, The Boring Company, and renowned national laboratories that define our mentality to radically improve our microreactors. We care deeply about our mission to reduce carbon emissions, and have fun while doing so from trivia nights to ski retreats.

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