In this work feedback control laws are designed for achieving three-axis attitude\ud stabilization of inertial pointing spacecraft using only magnetic torquers. The designs\ud are based on an almost periodic model of geomagnetic field along the spacecraft's orbit.\ud Both attitude plus attitude rate feedback and attitude only feedback are proposed. Both\ud feedback laws achieve local exponential stability robustly with respect to large uncertainties\ud in the spacecraft's inertia matrix. The latter properties are proved using general\ud averaging and Lyapunov stability. Simulations are included to validate the effectiveness of\ud the proposed control algorithms

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A novel controller for cranes employed in heavylift offshore marine operations is proposed. The control objective is to reduce the hydrodynamic slamming load acting on a product at water-entry of moonpool operations; at the same time the values of the wire tension must be kept within acceptable bounds.The control design is based on an extension of classical SISO feedback design to the case of not measurable controlled output.The effectiveness of the proposed design is shown experimentally. The experiments are carried out using a scale-model of a crane vessel with a moonpool. Experimental results show improvements with respect to a previous feedforward controller.

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