Ground-Track Adjustment Using Impulsive Control for Earth Observation Satellite

Abstract

This study proposes an analytical, near-optimal, impulsive control method to overfly predefined ground targets. A derived set of impulses, that adjusts the ground-track of satellite, compensates for ground-targets-crossing-errors existed in the nominal (uncontrolled) orbit. The proposed method yields a simple set of delta-v solutions that only consist of orbital revolution numbers, which is similar to the solution set of the well-known multiple-revolution Lambert's problem. Hence, in the proposed method, the only task required to achieve optimal solution is to find the optimal revolution number that minimizes the delta-v, which can be easily done with conventional search algorithms. It is shown that this simplicity of the proposed solution for single-target case can be easily extended to general two-and three-targets overflight cases. Numerical examples demonstrate that the proposed method enables the spacecraft to overfly all the designated targets within a prescribed time in J2-perturbed orbit environment. Impulse magnitudes and firing times of the proposed analytical method are compared with those of the results from a numerical optimization method.