Research on dynamics and deployment method for long space tether system

This paper studies the control strategy of the deployment for long space tether system. Dynamic characteristic of the long tethered satellite is researched and analyzed in the deployment process. The mathematical model is established through Lagrange Equation, considering the mass of the tether and the out-plane angle of the sub-satellite. Multi-deployment method is proposed according to the requirements of the deployment of the long space tether system. The deployment process is divided into several sections, and the length of tether in each section is optimized with differential evolution algorithm. The nominal control low is applied in every section. Numerical simulation results prove that the proposed control law could not only deploy the sub-satellite to the right location, but also reduce the maximum velocity of deployment of sub-satellite effectively. Multi-deployment method can satisfy the requirement of long tethered satellite deployment. It has theoretical value and can be used in the further research.