Interview with a DEDRA Payload Engineer

Please Introduce yourself

Alexander:
Hi, I am Alexander Hacker,  am 26 years old and study ESPACE in the 3rd Master semester. In October 2019 I joined the DEDRA team.

How did you become part of the MOVE team?

Alexander:
As an ESPACE student, this is right up my alley. DEDRA was originally planned as a standalone project with a whole satellite. Since the MOVE-team already has a lot of experience from launching 2 missions before, it just seemed logical to combine both projects and work together towards our goals. In May 2020, we officially became part of the MOVE team, and I think that overall everyone has benefited from working together.

What has changed in the time you have been part of the team?

Alexander:
Very much has changed! We went from working about 2 hours a week to almost 15 hours per week. The Team has been completely restructured and we now have dedicated System Engineering and Implementation Teams. This “liquid team” structure enabled us as a fairly new team to benefit from the expertise that other members gained while working on their subsystems.

 

What do you like about MOVE?

Alexander:
A project like MOVE is great for gaining practical experience in applying what you have learned in your studies. You can come up with concepts and have the freedom to pursue them. It provides tools and offers the opportunity to work together. You find interesting subject areas and have to solve problems you wouldn’t have thought existed.

 

What exactly is DEDRA?

Alexander:
DEDRA is the payload of the MOVE-III mission. The satellite platform on which the payload will be mounted is based on the MOVE-Beyond project. Our scientific goal is to conduct research on dust particles in lower Earth Orbit, at altitudes of 500 to 600 km. We want to detect and classify these particles and find out more about their mass, velocity and the direction they are coming from. There are several space dust models and we want to provide new in-situ data to improve the measurements. We also hope to collect readings of human-caused sub-millimetre space debris or micrometeorites.

 

How does the Particle Sensor function?

Alexander:
The particles are colliding with our sensor at a differential speed of 5 to 50 kilometres per second. Due to the high collision velocity, the particles turn to some extent into plasma and the sensor captures the electrons and ions of the plasma. We plan to determine what kind of matter collided by classifying the time and location of the impact and the mass and velocity of the particles. The raw data obtained will go to the ground segment managed by our Science Team and then be processed into science-data products.

What are you currently working on?

Alexander:
We are working on the detailed design of our DEDRA sensor. We are figuring out how to create a functional yet simple mechanical structure to facilitate the sensitive amplification electronics. Due to the high-frequency constituents of our measurement signals, the sensor collects 5 million samples per second on four measurement channels. This data stream has to be buffered and a digital trigger mechanism finds and filters out a few 100 microseconds of interesting signals.

 

What was your most difficult task yet?

Alexander:
Deciding on a final base architecture for the sensor. You have all these ideas and different designs, but if you want to move forward, you have to decide which one to pursue. The differences are sometimes marginal and other times tremendous, but in the end, each design has positives and negatives and we can only build one of them. We need to focus on our goal, and we can’t do that if we can’t decide on a design. However, alternative concepts will be explored further to some extent, either with less manpower or during dedicated “power-days”.

 

What was your most rewarding moment?

Alexander:
The completion of the System Definition Review (SDR). Hearing the opinion of experts in the respective fields is absolutely crucial and it just felt great when they told us that we did many things right. But also the MOVE Kick-offs are really nice, meeting a lot of new people, having fun and interesting conversations and welcoming them to the team.

 

What advice would you give to people who are curious about joining MOVE?

Alexander:
First and foremost, there should be an interest in our general mission. Our area of operation is very specific, but we still need people who cover many engineering disciplines. Key aspects include mechanical and electrical considerations to build a system that will work in a variety of extreme situations, whether at very cold temperatures, in zero gravity or under radiation. Balancing the necessary systems and keeping it as compact and lightweights as possible is often difficult, and requires collaboration with other teams. The implementation process must be meticulously executed and tested with great attention to detail. Once deployed, there is very little we can do from our ground station to fix any problems that may arise, so critical self-reflection and thoroughness are important. This may all sound very technical, but we also need people in non-technical areas like management or public relations. Without someone to manage our funding, coordinate teams, plan meetings and ensure efficiency, there would be a huge mess. Depending on what field you want to work in, the degree program you selected is secondary.