The demand of space applications has been increasing over the years. This has derivedin new satellites structures that required from precise and robust control management.The satellite design is evolving towards the development of lighter structures. The combinationof lighter structures with precise and robust control has arisen the problem ofstructure vibration control. The control design of structures with large appendages likeantennas, booms or solar panels has become a challenge. The flexible dynamics of theappendages needs to be considered when performing the attitude analysis of the satellite,since these parts can be easily excited by the environment perturbations such us gravity,gravity gradient or solar wind. The objective of these research project is to develop ahigh-fidelity model plant of a satellite with flexible panels and review different systemidentification techniques used to observe the states of the system. The equations of themodel are reviewed and the model is verified against a multi-body software, Adams. Thesensors and actuators are selected and modelled for the control of the rigid body and theobservation of the rigid and flexible body. For the implementation of the flexible structureobservations a technique based in Genetic Algorithm is applied for optimal sensor location.Finally, different system identification techniques are reviewed for the identificationof modal parameters and rigid body parameters. The results illustrate the performanceof the model and how the different system identification techniques are performed whenobserving the model states.