Deep-Space Optical Navigation for M-ARGO Mission

V Franzese,F Topputo,F Ankersen,R Walker

doi:10.1007/s40295-021-00286-9

Abstract

The Miniaturised Asteroid Remote Geophysical Observer (M-ARGO) mission is designed to be ESA’s first stand-alone CubeSat to independently travel in deep space with its own electric propulsion and direct-to-Earth communication systems in order to rendezvous with a near-Earth asteroid. Deep-space Cubesats are appealing owing to the scaled mission costs. However, the operational costs are comparable to those of traditional missions if ground-based orbit determination is employed. Thus, autonomous navigation methods are required to favour an overall scaling of the mission cost for deep-space CubeSats. M-ARGO is assumed to perform an autonomous navigation experiment during the deep-space cruise phase. This paper elaborates on the deep-space navigation experiment exploiting the line-of-sight directions to visible beacons in the Solar System. The aim is to assess the experiment feasibility and to quantify the performances of the method. Results indicate feasibility of the autonomous navigation for M-ARGO with a 3σ accuracy in the order of 1000 km for the position components and 1 m/s for the velocity components in good observation conditions, utilising miniaturized optical sensors.

Highlights

There is a recent growing interest in miniaturized interplanetary spacecraft [32]
The aim is to estimate the spacecraft state through the processing of the line-of-sight directions to a number of visible targets observed by miniaturized onboard optical sensors. The visibility of these navigation beacons is dictated by the relative geometry between the observer and the targets in terms of distances, phase angles, and Sun angles as well as the radiometric performance of the optical sensor used
An optimal beacons selection criteria has been exploited to assess the optimal couples of beacons to be tracked

Summary

Introduction

There is a recent growing interest in miniaturized interplanetary spacecraft [32]. The European Space Agency (ESA) has funded several interplanetary CubeSat mission studies like M-ARGO [46], LUMIO (Lunar Meteoroid Impacts Observer) [43], VMMO (Lunar Volatile and Mineralogy Mapping) [22], and CubeSats along the Hera mission [28]: Milani [12] and Juventas [15]. The autonomous navigation experiment of M-ARGO consists of determining the spacecraft state in deep space by tracking the line-of-sight (LOS) directions to a number of known navigation beacons. The noise covariance in Eq 36 is a valid assumption when the measurements are close to the observer celestial equator as happens in the M–ARGO scenario, while note that correlated azimuth and elevation modeling is required for acquisitions of beacons with high inclination with respect to the observer. Note that the current formulation considers the angles generated by LOS measurements to the navigation beacons These are acquired by image processing whose modeling is out of scope of this work. (1) First, the algorithm determines which planets are visible as function of the MARGO trajectory This is obtained by checking the apparent magnitude of the planets and their angle to the Sun as seen from the estimated position of the spacecraft. It is worth reminding that M-ARGO is tracking the optimal beacons

Limit Mag

Findings

Conclusions