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The European Solar Telescope (EST) is a 4-m class solar telescope that will include a multi-conjugate adaptive optics system (MCAO) integrated in the telescope optical path. Currently, the EST is in its preliminary design phase, in which different alternatives for the main telescope subsystems must be proposed and evaluated to meet the main scientific requirements. The availability of models to predict the performance in this phase is therefore essential. A global end-to-end model including the main telescope structure control, the active optics system and adaptive optics strategy is planned for the EST. This document presents the in-house model developed to evaluate the dynamic requirements defined for the telescope structure during tracking operation. First, those requirements specified for the EST during tracking operation are presented. Then, the whole process to obtain and validate the dynamic representation of the telescope structure from the mechanical model is explained. Main dynamic loads likely to affect the tracking performance such as wind buffeting initially characterized for the EST are described. A controller is tuned for closed-loop axes control to ensure trajectory tracking while rejecting the wind effects. Finally, a Simulink model for the evaluation of the tracking performance including the main elements identified for the EST is proposed. Preliminary results based on simulations and their effects on the final telescope structure design are presented. In addition, possible implications on the tip-tilt control strategy to reduce residual image motion for an accurate image stability are analyzed.
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