GNC Engineer – Actuation Systems Job Torrance area,California USA,Engineering

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus and technical excellence are decisive advantages - and we are building a team that can deliver real capability, not just concepts.

This is a rare opportunity to join at an early stage, where your work will directly shape critical systems, influence major technical decisions, and have immediate, real-world impact.

As a GNC Engineer focused on actuation systems at Castelion, you will build the control algorithms, models, and software that turn vehicle commands into precise physical motion.

You will own problems across actuator modeling, closed-loop control, system identification, hardware characterization, simulation, and flight integration. Depending on your experience, you may contribute to individual control loops or take ownership of complete actuation systems from requirements and architecture through hardware testing and flight.

This role is a strong fit for engineers who enjoy controls, electromechanical systems, hands‑on testing, and seeing algorithms directly affect hardware performance.

Responsibilities

Design, implement, and tune closed-loop control systems for flight vehicle actuators
Develop position, velocity, force, torque, and current control architectures as required by the actuator system
Model electromechanical actuator dynamics, including motors, transmissions, ball screws, control surfaces, sensors, structural loads, friction, backlash, saturation, and other nonlinear effects
Develop actuator performance requirements and support motor, gearing, sensor, and mechanical hardware sizing
Perform stability, bandwidth, robustness, disturbance rejection, and tracking performance analysis
Develop feed forward, filtering, compensation, anti‑windup, command shaping, and other control features to improve actuator performance
Perform system identification and parameter estimation using component, bench, and integrated test data
Build actuator models for high‑fidelity vehicle and 6‑DOF simulations
Implement control algorithms in embedded flight software and support real‑time execution constraints
Develop Software-in-the-Loop (SITL) and Hardware-in-the-Loop (HITL) test environments for actuator validation
Plan and execute hardware characterization and closed‑loop actuator testing
Analyze test and flight data to validate models, identify performance limitations, and improve control designs
Work closely with GNC, avionics, embedded software, mechanical, electrical, and test engineers to deliver integrated flight‑ready actuation systems

Basic Qualifications

Bachelor's degree in Aerospace Engineering, Mechanical Engineering, Electrical Engineering, Computer Engineering, or a related technical field
Strong fundamentals in feedback controls, dynamics, or electromechanical systems
Experience programming in Python, Rust, C/C++, Julia, or a similar technical computing language
Experience analyzing dynamic systems through coursework, research, internships, projects, or professional work
Ability to work effectively across software, electrical, mechanical, and controls disciplines

Preferred Skills and Experience

Experience designing and tuning closed-loop control systems for electromechanical or aerospace hardware
Experience with motor control, servo systems, position control, velocity control, force control, or torque control
Experience modeling DC, BLDC, or PMSM motors and their associated drive electronics
Experience with mechanical transmission systems such as gearboxes, ball screws, linkages, or rotary‑to‑linear mechanisms
Strong understanding of classical control techniques, including loop shaping, gain and phase margin, bandwidth, and frequency‑domain analysis
Experience with state‑space controls, observers, feed forward control, or disturbance estimation
Experience with nonlinearities including saturation, rate limits, deadband, backlash, friction, hysteresis, and compliance
Experience with system identification and correlation of analytical models against hardware test data
Experience with embedded or real‑time control software
Experience with sensors such as encoders,…