Approach maneuver for fly-around spacecraft based on spiral trajectory control

For the control pattern of spacecraft rendezvous, the impulse control method had been applied in common. But the control method had some deficiencies, for example, unsmooth trajectory and more energy was depleted. To the fly-around spacecraft, the helix-approach control algorithm based on a logarithmic spiral curve was introduced for the space rendezvous maneuver. Furthermore, the improved helix-approach control scheme with the extended Kalman filter (EKF) was proposed to estimate the entire state vector when some state variables were not available for measurement in a practical situation. Simulation results indicate that the proposed control scheme has better performances in the presence of external and internal disturbances.