Internal Research Fellow (PostDoc) in Mechanisms - Microvibration Isolation Technology

Internal Research Fellowship Opportunity in the Directorate of Technology, Engineering and Quality.

ESA is an equal opportunity employer, committed to achieving diversity within the workforce and creating an inclusive working environment. For this purpose, we welcome applications from all qualified candidates irrespective of gender, sexual orientation, ethnicity, beliefs, age, disability or other characteristics. Applications from women are encouraged.

This post is classified F2 on the Coordinated Organisations’ salary scale .

Location
ESTEC, Noordwijk, Netherlands  

The Mechanisms Section provides functional support to ESA projects and carries out technological research and development (R&D) in the fields of space mechanisms (such as for deployment and pointing or hold-down and release, solar array drives, and reaction wheels), tribology, pyrotechnics, and space mechanical systems for satellites and launchers.

You are encouraged to visit the ESA website: https://www.esa.int/

Microvibration is a design driver for high performance science and Earth observation missions. Better performing isolation systems could be used, either to isolate noise sources (typically mechanisms) or full payloads. In recent years, new isolation system technologies have been assessed. 

In particular, a new semi-active isolation system has been developed. The design includes 2 DOF collinear struts using electromagnetic shunt dampers with a negative resistance circuit for improved damping performance. These struts are built into a carefully selected hexapod configuration. To ensure the struts only see forces along their operational axis, two joints on top of the struts connect them to the hexapod. The entire design only uses compliant mechanisms, i.e. there are no tribological components creating friction losses or wear. The resulting system has a relative low mass, only uses a few watts of power, and acts as a fully passive system without any active control. The predicted performance of the full system corroborated by the first test results at strut level show this is a breakthrough technology that can enable future science and Earth observation missions, either by vastly improving the performance or simplifying the architecture.

You will continue the development of this isolation technology by further iterating on existing hardware and simulation models. Furthermore, new versions of the design may be developed, built and tested.

In particular, your research activities will be to: 

• conduct additional performance tests on the existing full breadboard, including tests using realistic noise sources such as reaction wheels.
• conduct performance testing in a thermal or TVAC environment, either at full breadboard or strut level.
• test the magnetic performance of the existing design.
• perform optimisation studies using improved multi-body simulation models to determine optimal tuning of flexure stiffness, coil parameters, negative resistance circuit parameters, strut length, flexure spacing, etc. 
• update a mechanical design based on the outcome of the optimisation process, also implementing lessons learned from the current design, such as mechanical alignment. Explore new flexure membrane geometries to achieve individually tuned axial and lateral stiffness of membranes.
• produce a new version of a strut design for performance testing in ambient and TVAC conditions.
• assess new functionality, such as passive compensation, to achieve a more uniform performance over the thermal range.
• assess the performance of the technology for a wide range of applications.

Knowledge relevant to the field of research

Research/publication record

Ability to conduct research autonomously

Breadth of exposure coming from past and/or current research/activities

Ability to gather and share relevant information

General interest in space and space research

Result Orientation
Operational Efficiency
Fostering Cooperation
Relationship Management
Continuous Improvement
Forward Thinking 

You should have recently completed or be close to completing a PhD in mechanical or aerospace engineering.
Preference will be given to applications submitted by candidates who have received their PhD within the past five years. 

•    experience with space mechanisms/mechanisms building blocks and related subsystems, as well as knowledge of space tribology and compliant mechanisms.
•    experience in the design, development and testing of mechanisms for space or aeronautical applications, and knowledge of simulation software (such as MATLAB, Simulink, COMSOL Multiphysics, ANSYS Maxwell, MSC ADAMS or LabVIEW) would be considered an asset.
•    thorough prior knowledge of the semi-active isolation system using electromagnetic shunt dampers with a negative resistance circuit for improved damping performance. This technology has been published widely.

The working languages of the Agency are English and French. A good knowledge of one of these is required. Knowledge of another Member State language would be an asset.

Other information

For behavioural competencies expected from ESA staff in general, please refer to the ESA Competency Framework .

For further information on the Internal Research Fellowship Programme please visit: Internal Research Fellowship

The Agency may require applicants to undergo selection tests.

In addition to your CV and your motivation letter, please add your proposal of no more than 5 pages outlining your proposed research in the "additional documents" field of the "application information" section.

At the Agency we value diversity and we welcome people with disabilities.  Whenever possible, we seek to accommodate individuals with disabilities by providing the necessary support at the workplace.  The Human Resources Department can also provide assistance during the recruitment process. If you would like to discuss this further please contact us at [email protected] .

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Please note that applications are only considered from nationals of one of the following States: Austria, Belgium, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Luxembourg, the Netherlands, Norway, Poland, Portugal, Romania, Spain, Sweden, Switzerland, and the United Kingdom. Nationals from Latvia, Lithuania, Slovakia and Slovenia, as Associate Member States, or Canada as a Cooperating State, can apply as well as those from Bulgaria, Croatia and Cyprus as European Cooperating States (ECS).

According to the ESA Convention, the recruitment of staff must take into account an adequate distribution of posts among nationals of the ESA Member States*. When short-listing for an interview, priority will first be given to candidates from under-represented Member States *.

In accordance with the European Space Agency’s security procedures and as part of the selection process, successful candidates will be required to undergo basic screening before appointment conducted by an external background screening service. 

*Member States, Associate Members or Cooperating States.