Analysis of the Relative Motion Characteristics of Millimeter-level Satellite Formations under the Influence of Earth Oblateness Relative Perturbation

With high-precision DEM (Digital Elevation Model) and GMTI (Ground Moving Target Indicator) as the demand background, the influence of J 2 zonal harmonic term perturbation on the relative motion of the millimeter-level short-range leader-follower satellites in near-circular orbit is studied through the relative perturbation method. An equation of motion that can describe the motion of the leader-follower satellites under the influence of J 2 perturbation in near-circular orbit is derived, and the characteristics of the trajectory of in-plane periodic motion are analyzed. Study shows that under the influence of the relative perturbation of J 2 term, the in-plane periodic motion of the leader-follower satellites in near-circular orbit is a symmetrical closed "drop-shaped" trajectory with a period of 2π/n. By comparing with the results of numerical simulation, the correctness of the conclusions obtained in this paper is verified. According to the research results, it can be known that only using thruster as the actuator to maintain the relative position can no longer meet the requirements of the long-term mm-level relative position maintenance. In the future, a new technical approach needs to be explored to achieve the long-term relative position maintenance with millimeter-level control accuracy.