Electromagnetic formation flight uses forces and torques to control the position and attitude of satellites in the formation.Satellites become independent of the fuel available on board.Also the contamination of optics or sensitive formation instruments

due to thruster plumes

is avoided.Based on magnetic forces

the control problem of relative motion for satellite formation flight is studied.The models of magnetic force and relative motion are presented.A nonlinear control law based on saturation function is designed.System stability is proved using Lyapunov’s stability theorem.The simulation of two satellites is also presented.The results indicate that the satellites in the formation are controllable under the electromagnetic force completely.