Design for minimum risk in remote maintenance system development for fusion power plant

The thesis develops a new design methodology for minimum risks at the early design phase by establishing a risk-based function structure and physical-effect abstraction of risk parameters for analysis and simulation. The methodology is implemented through a study case of the hexapod robot, a part of a remote maintenance system working inside the In-BioShield area of the DEMOnstration Fusion Power Plant. Several solutions were chosen during the preliminary analysis of this study case, including using thermal and magnetic shields with special materials, adding clearances to mitigate risks related to thermal expansion and using a shock absorber with unique fasteners for minimising vibration resonance impacts. A simulation model was constructed to evaluate the performance of these design solutions. The results confirm that risks are minimised satisfactorily with the new design approach. The study helps recommend a new design methodology for identifying and minimising risks in the early design stages.