The Dynamics of Arranging a Spacecraft Tether Group as a Triangular Constellation

Abstract: The method of arranging a tether group of four spacecraft as triangular beam constellation is considered in this paper. The group consists of a central spacecraft, from which the tethers are released, and three small spacecraft (satellites). After arrangement, the group is a triangular beam symmetric constellation of spacecraft stabilized by rotation with a certain specified angular velocity. When arranging the group, it is proposed to use a combined control method, which consists in the joint use of low-thrust engines located on satellites and tether release devices that ensure their smooth braking at the final stage of system arrangement after the engines are turned off. To select the control laws for the arrangement of the system, a mathematical model of the plane motion of the system constructed using the Lagrange equations is developed and used. To check the feasibility of the proposed control laws, a more complete spatial mathematical model of the system motion is used, which takes into account the motion of the spacecraft and satellites relative to their centers of mass, the extensibility and one-sidedness of mechanical links (tethers), disturbances during separation of spacecraft, inaccuracy in knowing the initial angular velocity of rotation of the system before separation, etc.