H∞ control of a satellite platform: coprime factors design versus multi-block approach

Two H_∞ control designs are successively applied to the problem of controlling the attitude of a satellite with a large solar array, in order to ensure the robust stabilisation of the platform and to maintain a good pointing. A loop-shaping procedure based on coprime factorisation is applied first. The obtained results underline the efficiency of this method, which is known to present attractive properties. Furthermore, it can be easily related to the more standard H _∞ approach, which suggests to use it to define more easily convenient H_∞ criteria. Such a combination is used to further improve the obtained results