Master´s Thesis: Proportional Piezo Valve for Electric Propulsion Feed Systems (m/f/d)

About this role

Join our fluid control equipment development team and help develop a proportional piezo valve for precise mass flow control in electric propulsion feed systems. Electric thrusters such as Hall-effect and gridded ion thrusters need a very stable, finely resolved propellant flow (typically xenon or krypton) in the low mg/s range. Piezoelectric actuators offer fast response, high resolution, and low power use, which makes them a promising alternative to conventional thermal throttles and bang-bang solenoid regulation.

However, effects such as hysteresis, creep, and temperature dependence must be understood and compensated. You will model, build up, and experimentally characterize a piezo-based flow control concept, and develop a control strategy for closed-loop mass flow regulation. Your Responsibilities Review the state of the art in mass flow control for electric propulsion, including thermal throttles, solenoid-based pressure regulation, and piezo valves Research state of the art of piezo actuators and trade different architectures (e.g.

stacked, amplified, piezo motors) for the given application Characterize the piezo actuator (stroke, force, hysteresis, creep, temperature behavior) and its effect on the valve’s flow area Assess the concept against typical electric propulsion requirements (flow range, leak rate, power consumption, operating temperature range) Build a physical flow model of the valve that links actuator stroke, inlet pressure, and gas properties to mass flow, covering the relevant flow regimes (e.g., choked and transitional flow) Integrate the actuator into a valve architecture and design a breadboard model Review existing test bench infrastructure with pressure sensors and a mass flow meter, adapt if necessary, and carry out flow characterization with inert gases Optionally, develop and implement a closed-loop control strategy (e.g., PID with hysteresis compensation) and evaluate its performance in terms of accuracy, resolution, response time, and stability Optionally, derive design recommendations for a flight-representative valve Currently enrolled in a relevant engineering program, ideally Aerospace Engineering, Mechanical Engineering, Mechatronics, Electrical Engineering, or a similar field Solid knowledge of fluid mechanics or gas dynamics; experience with control engineering is a plus Hands-on experience with lab work, test setups, or measurement technology (e.g., from working student jobs, engineering projects, or student teams) Programming skills in Julia, Python or MATLAB/Simulink for modeling, data analysis, and controller design Motivated, pragmatic, and self-organized Fluent in English; German and other languages are a plus Internship can be mandatory or voluntary Above average remuneration Guided but self-determined problem solving to realize your ideas Deep dive into the domain of commercial spaceflight and mobility Opportunity for an adjacent employment as working student or for thesis Flexible entry date, the sooner the better with flexible working hours Holiday entitlement above German standards