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Large radio-telescopes requiring accurate 'blind' pointing accuracy are often equipped with dedicated metrology systems
in order to correct for structural deformations. We present here a novel tiltmeter concept conceived specifically to
compensate for the fast, wind-induced deformations occurring on such large structures. This instrument combines the
typical accuracy and resolution of geodetic devices with an unique capability of recovering quickly from large
saturations: this condition often occurs during fast slewing of the antenna. Moreover, the device features a reduced
sensitivity to in-plane accelerations. All this allows its installation in favorable positions concerning the observability of
the structural deformations to be detected and corrected, thus simplifying the processing from raw instrument data to the
pointing correction to be applied. The instrument has been subjected to a thorough characterization and qualification
process, by means of extensive tests both in the lab, using a dedicated testbench, and on the ALMA-EU antenna
prototype. This activity allowed assessing other critical aspects for the final application, in particular easiness of
installation, simplicity of mechanical and electrical interfaces, robustness, reliability and very limited maintenance
requirements. The device will be installed on the ALMA-EU production antennas.
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