This paper introduces an autonomous navigation concept based on optical observations of the Sun and selected planetary bodies. The concept is self-contained and independent from the mission ground segment. It enables autonomous navigation of spacecraft anywhere in the solar system, including spacecraft flying through the Asteroid Main Belt (AMB). Initially, the novel navigation concept is introduced within its historical and technological context. The sensor technology involved, the navigation observables and their accuracy is discussed. Subsequently, the navigation performance - i.e. position and velocity errors - is analysed for two selected orbit scenarios: an Earth-like orbit around the Sun and an orbit within the AMB at 2.8 AU from the Sun. For each test scenario two estimators are used: an Unscented Kalman Filter (UKF) accounting for third body gravitational perturbations and a Particle Filter (PF). The results are evaluated in terms of the standard deviations of the available measurements, the frequency of the observations and the number of observations simultaneously participating in the sensor fusion process. The optical navigation concept introduced here makes use of a coupled star-Sun tracker to determine direction to the Sun, optical Doppler measurements from a resonance-scattering interferometer to determine the spacecraft radial velocity relative to the Sun and optical cameras to determine the line-of-sight vector towards planetary bodies. The problem of orbit determination is solved at first for an orbital distance of 1 AU from the Sun. This initial test evaluates the benefits of the additional planetary line-of-sight observations as compared to previous concepts based on observations of the Sun only. In a second step, the two implementations based on the UKF and PF are compared with the purpose of evaluating the sensor fusion capability of the overall system. The UKF and the PF solutions are assessed in terms of accuracy of the positioning solution, convergence efficiency and computational requirements. Finally, the performance of the proposed concept is evaluated for the KaNaRiA mission scenario. KaNaRiA is a feasibility study of an asteroid mining mission targeting asteroids in the main belt. Part of the KaNaRiA mission architecture consists of several prospecting spacecraft which will fly autonomously to different target asteroids. In the context of the KaNaRiA mission analysis, a parking orbit at 2.8 AU from the Sun has been selected. The orbit is characterized by slow varying geometry relative to the Sun and good observability opportunities of the near planet Jupiter.
«This paper introduces an autonomous navigation concept based on optical observations of the Sun and selected planetary bodies. The concept is self-contained and independent from the mission ground segment. It enables autonomous navigation of spacecraft anywhere in the solar system, including spacecraft flying through the Asteroid Main Belt (AMB). Initially, the novel navigation concept is introduced within its historical and technological context. The sensor technology involved, the navigation o...
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