Static stiffness measurements and the alignment of the Big Wheel prototype

The static stiffness measurements and the alignment exercise on the Big Wheel prototype are reported in this paper. The prototype was loaded in a similar way it will be loaded in its use and the displacement of the prototype was measured. The used measurement methods were the digital photogrammetry and linear displacement transducers. The data obtained from the measurements is analysed and compared to the analyses results computed with finite element (FE) models. A good correspondence between the measured and the computed values was found. The alignment exercise was performed when assembling the components together. The Big Wheel was aligned with theodolites and levelling machines. The alignment was verified with digital photogrammetry. The prototype needed to be re-aligned once in order to achieve the sufficient alignment accuracy. The report examines the design of the Big Wheel and the procedures of assembly in a critical way giving propositions of improvement for the final tracker outer barrel.