Master (MSc) Thesis ''Structural Dynamics Test Jig for Spacecraft Equipment''

Mechanical disturbances from spacecraft equipment, such as reaction wheels, can couple into the satellite structure and affect

sensitive payloads. Previous work at OHB has investigated methods for estimating reaction-wheel parameters from measured waterfall

plots.

The purpose of this thesis is to develop a simple and cost-effective experimental setup for characterizing relevant dynamic

parameters and evaluating structural or damping improvements.

The proposed concept is a flexible plate or table supported by springs and instrumented with accelerometers and/or force sensors.

The work will combine analytical modelling, finite element analysis, and measurement data to identify parameters such as

stiffness, damping, and modal properties.

The long-term objective is to establish a fast in-house method for comparing structural and damping concepts before formal

qualification testing.

The student will design and model a simplified test setup, define suitable measurement methods and investigate how sensor data can

be translated into physical parameters of the test object. The method will first be verified using simulated data with known

parameters.

The core scope includes modelling, parameter identification, test-jig design and uncertainty assessment. Depending on progress,

available hardware and budget, the thesis may also include manufacturing and experimental testing of the setup.

The thesis will follow a top-down approach, starting with a deliberately simple and well-understood mechanical system. Once the

modelling and parameter-identification method has been validated, individual design changes can be introduced and their effect

quantified relative to a baseline.

If time and resources allow, the work may also include manufacturing of the test jig and validating the method experimentally

using a motor, engineering model or available reaction wheel.

A secondary application may be investigated using impact-hammer excitation to measure transfer functions through brackets or

structural interfaces.

• Master's-level student in Mechanical Engineering, Engineering Mechanics, Aerospace Engineering, Applied Physics or related

field.