In the paper, the optimal control analysis for a notional constellation consisting of two Sun-synchronous Martianorbiters(Orb-A and Orb-B) is described that can provide consistent illumination and efficient coverage. Theperturbations due to the gravitational force from Sun, Jupiter and the non-spherical gravity field of the Mars areutilized to establish a framework for deriving the motion equations of the spacecraft. A nonlinear model is developedthat describes the dynamics of the system and the model is converted into a linear-like structure. Controlaccelerations are calculated to maintain the spacecraft in the constant orbit by employing an optimal nonlinearcontrol approach, known as the State Dependent Algebraic Riccati Equation i.e. the SDRE technique. Numericalresults are presented and analyzed. The same optics camera is loaded in Orb-A and Orb-B that provides efficientimaging for mapping. A typical application is demonstrated using the constellation consisting of the Orb-A and Orb-B in the similar orbit that provides the maximum coverage and at the same time provides minimum revisit time. Thecoverage request is given and the simulation is initialized with the Orb-A and Orb-B orbiting the Mars with its initialconditions. Simulation results are given for the different ground points and area targets. An interesting applicationscheme is discussed at the end of the constellation lifetime. Orb-A is controlled to land on the desired Martianground and Orb-B is manoeuvred into a special orbit with daily repeating ground traces. Then the Orb-A landingpoint is visited by Orb-B that repeats at the same time every solar day. The daily repeating ground traces of the Orb-B in the Sun-synchronous orbit are shown.
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