Starting procedure for space-based laser trackers to autonomously reach distant reflecting targets by means of very narrow beams
Creators: name:  J.M. GAMBI 
name:   M.L. GARCIA DEL PINO 
name:   J. MOSSER 
name:   E.B. WEINMULLER 
Publisher: name: Proceedings of  the 9th European Conference for Aerospace Sciences. Lille, France, 27 June - 1 July, 2022
Year: 2022
Subjects: SPACE DEBRIS
OBSERVATION
ORBIT DETERMINATION
ACTIVE DEBRIS REMOVAL

description: This contribution is a continuation of the work introduced during the 3AF-OPTRO2022 Conference [1]. We present here an updated starting procedure for the more general case where the target, D, is at long orbital distance to the tracker, S. Here, S is also assumed capable to reach D with very narrow laser beams. Due to the large orbital distance from S to D, only a small number of shooting directions can coincide with the LOS directions to reach D. Therefore, this work can help to implement autonomous and secure FSO communications between some particular LEO emitters and GEO receivers as well as to achieve other similar goals. Since the orbital distance between S and D may be very large, the only realistic starting strategy for the emitter to be autonomous is to determine the instants, if any, at which the observed angular motion of the receiver from the emitter becomes zero, see [1]. Then we show that even assuming that S is capable to determine these particular configurations with the highest accuracy available at present, the success of the subsequent shooting actions can only be guaranteed by using both the p-N tracking formulae in [2] and the relative p-N equations of D with respect to S introduced here. This is because unlike current procedures, the implementation of these formulae and equations, accounts for the gravitational gradient along the trajectories of the narrow laser beams from S to D, see [1]. Additionally, our updated method accounts for the different behavior of the clocks on board of S and D, as this is the case in the usual procedures implemented for accurate space navigation and geolocation. Finally, we note that the new equations approach equations in [1] in case that the trajectories of S and D become close, so that the difference in the respective corrections to the current predicted locations are of higher order. Hence, both the starting strategy and the equations introduced here can become a part of the general procedure presented in [3,4] to deal with arbitrary shooting actions. References [1] J.M. Gambi, M.L. Garcia del Pino, J. Mosser and E.B. Weinmuller, Starting procedure for LEO trackers to autonomously shoot at reflecting targets in close trajectories using very narrow laser beams, paper 80-212, 10th International Symposium on Optronics in Defense and Security, Versailles 1-3 February 2022 [2] J.M. Gambi and M.L. Garcia del Pino, Post-Newtonian tracking formulae to increase the shooting accuracy of autonomous LEO laser trackers, Advances in Space Research, 67, 2282-2303 (2021), doi:10.1016/j.asr.2021.01.028 [3] J.M. Gambi, M.L. Garcia del Pino, J. Mosser and E.B. Weinmuller, Computational modeling and simulation to increase laser shooting accuracy of autonomous LEO trackers, Photonics, 8, 55-61 (2021), doi:10.3390/ photonics8020055 [4] J.M. Gambi, M.L. Garcia del Pino, J. Mosser and E.B. Weinmuller, Trailing formations of lightweight spacecrafts to deflect NEAs by means of laser ablation, Acta Astronautica, 190, 241-250 (2022), doi:10.1016/j.actaastro.2021. 10.006.AA 2021