Meet the team - interview 6: Michiel Kruiff

Meet Michiel Kruiff, Lead System Engineer for prime contractor Delta-Utec on the YES2 project.

What's your role at Delta Utec?

I am Technical Director of Delta-Utec and Lead Engineer for YES2. That means I’m responsible for technical issues in the design work, tests and studies that Delta-Utec performs.

How did you get involved in the YES project?

My colleague Erik van der Heide and I started Delta-Utec eleven years ago with the objective to develop a tether system for use in space and actually fly it.

We were inspired by Dutch astronaut Prof. Wubbo Ockels. He introduced us to the idea of space tethers and the SpaceMail concept in 1994. In 1996 we made a proposal to build the first YES satellite as part of TEAMSAT on Ariane 502. In 2002 we developed the idea for YES2 with help from Prof Ockels.

What's your role in the project?

As Lead Engineer of YES2 I have had at least three full-time jobs:

I’m responsible for the overall design of YES2, and as it is an educational project that comes with selection, motivation, education and guidance of the students.

I‘m also responsible for the System Engineering. This means I make sure that all the sub systems of the satellite: hardware, electronics and software work together, as well as oversee the tests and try to recognise and interpret any potential anomalies highlighted by the data we get.

Finally, I am Prime Investigator for the tether, which involves design and testing, mission operations and contingencies planning. I have been working on this technology for over a decade.

On top of that, I have been providing and reviewing presentations, summaries and reports to ESA for reviews and on request.

What specific areas have you been involved in on the project?

I have supervised about 70 student interns working at Delta-Utec and about 350 students working remotely on YES2. This involves giving out daily tasks and helping them find answers to technical questions. It’s important that they feel what they are doing is contributing positively to the project, especially in the early design phases when there are only paper designs and models.

As Lead System Engineer my task is to recognise from a higher level those relationships and interactions between the different components that others may overlook. I need to go deep into design details with the students, down to individual nuts and bolts, as they are not experienced and usually have to leave the project before their work is complete. Somebody has to transfer knowledge of previous work done to the next student assigned to that area of the project. This gives me a broad, deep understanding of the design.

I have to be very critical, often more than students are used to, to ensure a level of quality approaching that of all professional ESA projects. We developed several web-based tools that recorded every step of the design process in minute detail. This enabled students to propose solutions to design problems and make changes in an organised way, wherever they were based. In the end though, it’s me who has to give the final go-ahead or come up with an alternative to something that doesn’t work.

I have worked with the tether a lot. Although it seems simple, it is very difficult to model its behaviour precisely and in micro gravity it often acts counter-intuitively. For example, when you pull on it, it get’s shorter! And if you try to decelerate it, gravitational and Coriolis forces mean it might end up travelling faster! We also tested the deployment as realistically as possible and introduced a lot of safety features to ensure that it is reliable and safe. Quite a challenge if you imagine deploying 30 km tether in a 5 meter test facility!

All these tools and test facilities were developed and used by students, as well as the work done to develop and qualify a re-entry capsule and qualification is a very rigorous process. So, you can see that YES2 is much more than just a satellite: it’s become a unique learning experience for everybody involved.

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