Vibration isolation is essential for spacecraft payloads, where both launch loads and on-orbit micro-vibrations can degrade performance. Passive isolators are favoured for their simplicity and reliability but face trade-offs between low-frequency performance, stiffness, and compactness. This thesis introduces a topology optimisation framework for designing passive viscoelastic vibration isolators that distributes aluminium and nearly incompressible rubber within the design domain, moving beyond conventional constrained-layer damping layouts used in literature.

The framework combines a modal design approach with a bi-material finite element formulation using selective reduced integration to handle incompressibility. Modal objectives are defined through rigid-body dominated eigenfrequencies of the combined isolator–payload system, with damping enforced via Q-factor constraints.

Each optimised layout consists of a main load-carrying structure that provides stiffness and smaller damping substructures that create localised regions of energy dissipation. They adapt their shape and location to the inertial properties of the setup and targeted vibration mode, strategically placing viscoelastic material where it contributes most to damping without compromising stiffness. In doing so, the framework enables novel damping mechanisms and tunable multi-directional performance, offering an insight for future passive isolation design in vibration-sensitive applications.