Analysis of libration impact on the deorbit mission of space electro-dynamic tether

Using the electro-dynamic tether system for space debris deorbit has a broad application prospect. Under the torque generated by Lorentz force and gravity gradient, the electro-dynamic tether librates along the local vertical. Base on Lagrange principles, the attitude dynamic associated with in and out-of-plan libration is established at first. The international earth's magnetic model, the Lorentz force and torque are calculated. Finally, by combining the attitude dynamics model and Gauss perturbation equation, the numerical model for electro-dynamic tether deorbit is established, and both the libration and non-libration deorbit mission are simulated, respectively. Simulation results show that the in and out-of-plan libration exist and have an obvious effect on the deorbit system. Only considering the attitude of the electro-dynamic tether system, orbital elements change can be convinced.