ANALYSIS OF THE GRABBING POSITIONING AND RELEASE MECHANISM PERFORMANCE SENSITIVITY TO ALIGNMENT @LISAcommunity

Uploaded July 2022 | Updated September 2026, 57 minutes ago

The transition from the launch lock environment to science operations is particularly critical for LISA. In LISA-Pathfinder the Grabbing Positioning and Release Mechanism (GPRM) showed some anomalies and out-of-spec release velocities.

Within the phase-B1 tasks the GPRM is being studied and upgraded to comply with the LISA requirements. The release sequence implemented in LPF needs to be consolidated for LISA in a reliable and autonomous procedure, due to the increased distance from Earth and the larger number of Test Masses (TMs). One of the suspects in degrading the GPRM performance is the misalignment between the two nominally symmetrical mechanisms on two sides of each TM.

Using state-of-the-art multibody dynamic simulations, the TM grabbing phase is reconstructed and the sensitivity to misalignments and tolerances is investigated.

Authors: Matteo Tomasi, Edoardo Dalla Ricca, Davide Vignotto, Carlo Zanoni, Daniele Bortoluzzi, Andrea Moroni, Paolo Radaelli
Presenter: Matteo Tomasi

ANALYSIS OF THE GRABBING POSITIONING AND RELEASE MECHANISM PERFORMANCE SENSITIVITY TO ALIGNMENT

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