Design of a Solar Array Drive Mechanism for CubeSats: A scalable, modular and reliable SADM for CubeSats in Low-Earth orbit

CubeSats have risen in popularity since its first launch in the year 2003. The low mass, lower launch cost, lower development cost, possibility for piggyback with larger satellites and lower development time involved compared to larger satellites have opened them to be commercialised by private companies. In contrast to being used for...

Compliant Full Film Lubricated Bearings: Concept Design & Development

Full film lubricated bearings are machine components that excel in their ability to carry high loads with very little friction. Their main archetypes, passive hydrodynamic and active hydrostatic bearings, are used in a wide variety of applications, ranging from hydraulic pumps to high precision machine benches. They are most commonly lubricated...

Modelling adhesion and friction in contact problems

The main objective of this thesis is to obtain a better understanding of adhesive contacts and their frictional behaviour. Both natural and man-made surfaces are rough over a wide range of length scales. Tribological studies of rough surfaces need to account for the interactions between these asperities. In this work a sim- ple atomistically...

Plastic deformation of self-affine rough metal surfaces under contact loading: A green’s function dislocation dynamics analysis

Modelling verification and influence of operational patterns on tribological behaviour of wheel-rail interaction

Verification of the explicit finite element (FE) model with realistic wheel-rail profiles against the CONTACT model, which has not been sufficiently discussed, is performed by comparing the resulting shear stress, slip-adhesion area, etc., obtained from the two models. The follow-up studies using the verified FE model on the influence of the...

Green's function molecular dynamics approach: Proportionality between area and load

Green's function molecular dynamics: Including finite heights, shear, and body fields

The Green's function molecular dynamics (GFMD) method for the simulation of incompressible solids under normal loading is extended in several ways: shear is added to the GFMD continuum formulation and Poisson numbers as well as the heights of the deformed body can now be chosen at will. In addition, we give the full stress tensor inside the...

Experimental Investigation of Adhesion and Friction Phenomena of Ultrananocrystalline Diamond (UNCD) and Aluminum Oxide in MEMS

This thesis aims to provide the latest progresses on the experimental investigation of friction and adhesion phenomena, occurring at the nanoscale in microelectromechanical systems (MEMS). I have studied and characterized the interaction between MEMS sidewalls in contact and sliding one onto another. Ultrananocrystalline diamond (UNCD) and...