Come join the hybrid project!
Do real rocket science next to your degree
What you should know before applying
As you probably understand, developing a rocket motor is tough work. The descriptions underneath outline the positions we want filled, but you should expect to have to go beyond that outline. There are ten positions to fill, but we don't necessarily expect to recruit ten people. That's why we keep saying: you have to enjoy learning new things while working with us. We strongly recommend reading the presentation of each system on the "Subsystems" page before applying.
Did you come here looking for the leadership positions? Click the button below to get to their page!
As the system leader for the motor group you will be working on coordinating many different disciplines for development and testing the student-developed hybrid rocket motor for Propulse. The engine is one of the most multi disciplinary parts of the rocket, and has aspects of electrical- and mechanical engineering, computer science, chemistry, physics and material science. The whole system is normally divided into 3 subsystems; the OX system (internal gas system), the burn chamber, and the filling station (external gas system). In total there are 7-10 members in the motor group. Your job as system leader is therefore to coordinate these subsystems. This will involve having a good understanding of the system in its entirety, and assure compatibility and cooperation between both the parts and the members. Parts have to fit together, and the only way to make sure of this is that people work together. It is of course natural that you yourself have a technical responsibility as well in the group, and using your expertise.
This year we experienced delays and adversity in many parts of design, production and testing. This is the nature of the system we are working on, there are always problems to expect while problem solving. The most important task of a system leader for the engine group is to always keep up the morale and make the rest of the group look onwards. An example of this we experienced during the last year was when we decided to switch to a pre-purchased engine (COTS). Strict deadlines can lead to haste in design and execution, and potentially not so user-friendly products. What we experienced was that we would have saved a great deal of time while planning, rather than rushing for a solution quickly. It is important to always keep one eye on the future, and consider how to get there the fastest.
Requirements: No specific academic background, but quick to learn. Previous leader experience helps, but is not a requirement. Encouraging and diplomatic.
Electrical systems engineer, OX system
As the electrical systems engineer of the OX system, you are responsible for the electronic and sensor equipment of the “cold” part of the rocket motor, namely the gas system that ensures a steady supply of N2O to the burn chamber. The OX system primarily consists of a gas tank with valves of various shapes and sizes attached to it. These valves must be controlled remotely and to some extent be automated - you will be working closely with the control engineer. The system is being developed from our test article known as the “test bench”. It consists of a tower housing the N2O tank, a “bench” that straps the burn chamber to the ground and a stand where most of the valves and electronics are attached. The primary objective of the test bench is to test and verify concepts that may be used when the motor is ready for integration into the rocket, and you will be cooperating with your counterpart on the filling station in designing and installing the necessary sensors in order to get reliable test data. Up until now, we have needed measurements of temperature, pressure, force and mass flow (which has proven to be surprisingly challenging), so one of your tasks will be to improve and maintain this sensor system. In addition to sensors and valves, the OX system needs a heater in order to maintain a pressure of 60 Bar. We have no perfect solution to this yet, so there’s plenty of room to get creative!
Our greatest challenge so far has been to get reliable data for mass flow as well as effective heating. These are two very important aspects of the motor development. Mass flow is our most valuable data point after motor thrust force, as it is the most direct and reliable way to decide what adjustments need making in the burn chamber - which in turn affects the thrust. Effective heating is essential in order to be able to fire the motor, as the tank pressure will be dangerously low at low temperatures.
Requirements: must above all be motivated and able to work independently. Must be interested in learning new things and cooperating with others. Must be comfortable with Ohm’s law and its usage. Should have some experience with electrical systems such as the ones found in RC models like drones and cars, and be comfortable with the idea of using 230V creatively. Should have experience with or understanding of basic sensoring principles. It is of great help to have some experience with “tinkering”, but this is something you will learn either way.
Electrical systems engineer, filling station
As an electrical systems engineer for the filling station and test bench your main task is to develop the electromechanical system for the hybrid rocket motor for Propulse. You are gonna work together with the motor team, where you discuss solutions for both the electrical and the mechanical systems. This gives you an opportunity to experience the whole system, from an electrical, mechanical and code perspective. Together with the rest of the group you are gonna test the motor system, where the objective is to get good readings from the engine behavior and iterate on that.
This year the testing has been focused on the fueling system. This is a system that’s composed of an Arduino microcontroller with relays and a radio controller. The readings we have taken are temperature, pressure and force, and has been logged through a datalogger, which has then been sent to a computer for further analyzes.
Requirements: Understand Ohms law, a bit about relays and its a plus if you understand both mechanical and electric systems.
Mechanical engineer, OX system
As the mechanical engineer of the OX system you are part of the group developing our own hybrid rocket engine. Specifically the part of the group that supplies the engine with oxygen. in our case nitrous oxide. This involves designing a system including a pressure vessel, actuators, valves and the fixtures for these.
Part of the job is also testing the design. It is very rewarding to see your design evolve throughout the year. You will see what works and what doesn’t and where it is important to improve.
Recommended knowledge: You have to like working in a team, and in groups with other people. Be prepared that you may have to do some research and information gathering on your own. Some knowledge around basic mechanics and material engineering is recommended, but not a requirement. During the project you will work a lot with the computer aided design program Solidworks, so some knowledge about that or similar types of programs may be good to have.
Mechanical engineer, filling station
As a mechanical engineer working on the filling station, you are primarily responsible for everything mechanical and much of the practicality surrounding the design and production of the system. The system is part of the motor system and has the task of filling the rocket with oxidizer, in our case liquid nitrous oxide. In addition, other functions such as the installation of cameras and transmitters in connection with these needs to be facilitated.
Important focus areas for the position:
- The rocket must be filled safely, reliably and efficiently.
-Coordination with ox system.
It is relevant to look at the test bench (used for testing the rocket motor) during system development.
Applicants first and foremost need a desire to learn! It is easy to develop an interest in rockets and aerospace as a member of Propulse. The most important thing is that you want to do a good job and develop your skills, but of course there is an advantage of knowledge and experience.
- To be a student in a relevant study program.
- Practical experience, e.g. certificate of completed apprenticeship.
- Interest in rockets, rocket engines, aerospace etc.
- Know about piping systems, valves, seals etc.
-Know about pressure, temperature, aggregate states and how they affect each other.
Mechanical engineer, burn chamber
As a mechanical engineer working with the burn chamber you are a part of the group developing a hybrid rocket motor for Propulse. The position mostly concerns designing and producing the burn chamber, the part of the rocket where the fuel is mixed with the oxidizer, ignited and propelling the rocket forward. This subsystem experiences extremely high temperatures, high pressure and other mechanical challenges you need to take into consideration while working. In this position you will be working closely with other members of the motor group from different disciplines, as well as people from different systems such as fuselage and fins, which are directly affected by the design of the burn chamber.
The main focus this year has been on the test engine, integration of the test engine to our test bench, and the tests themselves. At the same time much of the work has gone into finding solutions for integration of the final engine to the rocket. The tasks have been varied. One day you find yourself sitting at the office doing design work, and the other day you might be out on the test field with the rest of the motor group doing tests.
The biggest challenges this year have been to find the right loads and forces that affect the engine while running. Close cooperation with the simulation group have made this possible. There have also been some challenges doing the design, while trying to keep the production methods in mind. While working with designing we have had to ask people with more experience for tips, and read articles and books to find the best design solutions.
Requirements: You have to enjoy working in a team, and in groups with other people. Be prepared that you may have to do some research and information gathering on your own. Some knowledge around basic mechanics and material engineering is recommended, but not a requirement. During the project you will work a lot with the computer aided design program Solidworks, so some knowledge about that or similar types of programs may be good to have.
As a control engineer for the motor, you will have two areas of focus, namely the software and control system of the motor. The main objective is to provide a means of operating the OX system valves, which includes control for valve actuators, but also a means of deciding when to start and stop the engine in order to reach the target apogee as accurately as possible. Otherwise, there are other available control tasks such as creating the Kalman filter for motor relevant sensors in collaboration with Avionics/Recovery.
You will be the go-to person for programming responsibilities. This mainly includes writing:
The program to operate the test bench, particularly the individual valve actuators,
Aiding the collection and log of sensor data together with the Electrical systems engineers,
Motor functionality into the rocket flight computer through, for instance, some states in a finite state-machine,
Small scripts to test new equipment or sensors.
Here, one has the choice to start completely from scratch, but also to build from last year’s project.
Not only should the motor control engineer be responsible for the control of the engine system, they should be able to provide consultation on the general engine instrumentation. This would include helping decide the different actuators required and finding ideal mass flow measurement techniques, for instance upgrading from the mass measurements used last year which was quite challenging.
Recommended knowledge: Great teamwork and a keen interest to learn new things. Working in control also warrants knowledge in basic control theory and instrumentation. Otherwise, another important skill is programming in C/C++, but also some embedded programming as we work a lot with microcontrollers.
As an injector and nozzle engineer you will be working on calculating and simulating the mass flow through the injector right before the combustion chamber, and the nozzle after the combustion chamber. This is with the goal to eventually reach designs that can be tested and used for the final rocket.
The purpose of the injector is to deliver the liquid oxidizer as a highly atomized spray into the combustion chamber, so that the droplets can quickly evaporate into gas and partake in combustion. Additionally, the small injector orifices function as the mass flow rate limiter of the system. The mass flow rate of oxidizer is one of the most important factors of the rocket’s overall performance. This is particularly because of the resulting O/F ratio, or oxidizer to fuel mass ratio. The oxidizer we are using is N2O, which has a very flat curve in regards to efficiency or ISP. This means that even if the O/F ratio is off by a considerable margin, the efficiency will not be harmed substantially. This is not the case for other oxidizers such as liquid oxygen or H2O2. Regardless, knowledge of the O/F ratio inside the burn chamber is essential to understand and develop the rocket motor.
The previous holder of the position was a master student, and focused on the injector design for his thesis. It is recommended that you read this thesis thoroughly, as nitrous oxide injection is a complicated problem. However, much of the knowledge needed will be available from reading this thesis alone. The idea of having masters students work for Propulse is to build up a knowledge base of proper rocket science, so that future members can learn what they need quickly. Your role will consist of being a person in the team that understands the science behind what the team is doing along with the combustion engineer, and to further build upon this knowledge base for the future.
Applicants should have a particular interest in fluid simulations (CFD), and preferably be experienced with Python or C++
As a test engineer your main responsibility will be organising the motor tests for Propulses hybrid engine. Your tasks will consist of, together with the team, finding the best solutions to make the tests be safe, smooth and precise. Here you will contribute with organising the logistics, and in the long run work towards a permanent testing facility. This position is for you who think about health and safety, you are tidy and structured, you like to have things organised and aren’t afraid to fix problems that arise. As a bonus are you almost guaranteed to be present when we eventually get a flame spitting rocket engine.
Furthermore, this position does not require any specific background, but you will be able to contribute with your expertise to solve relevant problems both in the engine group and in the rest of Propulse.
As a chemist in the engine group, you will work on researching possible combinations of fuel, as well as the dimensions of the inside of the combustion chamber. This is one of the positions that is farthest from what one would to learn in school, and will involve a good deal of reading. Much of the evolution of the hybrid rocket engine is based on empirical testing and iterative design. This requires a place to start, given from quantitative calculations the projected engine behavior, but this starting point is never correct. Development therefore also requires a more qualitative theoretical understanding to propose changes, suggestions for which direction parameters should be adjusted. An example: Test data says that the thrust is too low, what do you do? The combustion chamber can be made longer to give a larger surface area, but this increases the weight. How about changing the geometry of the fuel rod from hollow circular to star-shaped? Volatile chemicals can be added to the solid fuel to increase the rate of combustion, but is the fuel still mechanically stable enough after this? How about adding metal powder to increase the combustion temperature? These are questions one must ask oneself while developing a rocket engine.
Knowledge: Great interest in rocket motors. Good thermodynamics and fluid skills help a lot.