Ponche, AlisonMarcos Esteban, AndresOtt, ThomasGeshnizjani, RaminLoehr, Johannes2024-01-192024-01-192023-06-01Acta Astronautica, (2023), 207, pp: 340-3520094-5765https://hdl.handle.net/10016/39383Current and future space observation missions need to perform many large-angle, multi-axis slew maneuvers between observations while keeping the scientific instrument's attitude in a safe region. The state-of-practice typically divides each multi-axis maneuver into a series of single-axis sub-maneuvers, each of which is computed by restricting its guidance solution to the exact spacecraft momentum capacity. This ensures that the constraints are explicitly considered and results in a simple on-board implementation of the guidance algorithm, but is time-consuming and non-optimal for the whole multi-axis maneuver. Addressing this issue, this article presents a novel analytical guidance approach that relies on the convexity of the permissible attitude zone. The proposed guidance is time-optimal for a given spacecraft design and set of admissible observation targets. Both guidance approaches are compared using a multi-body/multi-actuator benchmark spacecraft, whose complex repointing phase requires an autonomous on-board guidance computation. It is shown that the proposed approach is systematic and that the reduction in maneuver time, compared to the state-of-practice approach, is considerable.eng© 2023 The Authors. Published by Elsevier Ltd on behalf of IAA. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Atribución-NoComercial-SinDerivadas 3.0 EspañaConstrained guidanceMomentum envelopesOnline computationresearch articleAeronáuticahttps://doi.org/10.1016/j.actaastro.2023.03.020open access340352ACTA ASTRONAUTICA207AR/0000033588