This thesis deals with the analysis of the load behaviour of a prototype of the Stewart platform, which was developed and built at the Faculty of Mechanical Engineering in Ljubljana. It is a mechanism consisting of two plates represented by two irregular hexagons and six identical hydraulic cylinders connecting them. Using inverse kinematics, the maximum rotation angles of the hydraulic mechanism (its moving platform) were analytically determined. This was performed under the assumption of idealized connections at the points, where the ends of the hydraulic cylinders are attached to the platforms. A calculation was carried out using a numerical model based on FEM. The configuration of the hydraulic mechanism was also changed, and an analysis was conducted on how this affects the maximum rotation angles and the loads in the hydraulic cylinders. Finally, measurements (pressures, displacements) were carried out on the existing prototype platform. It was determined that the configuration of the Stewart platform affects both the maximum rotation angles and the maximum loads in the hydraulic cylinders. It was further determined that the loads in the hydraulic cylinders are most influenced by the rotation of the moving platform around the vertical axis.
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