Dynamic properties of the frame structure for mounting an electrical propulsion thruster onto an orbital transfer vehicle

Lunar exploration is one of the major future development paths for spaceflight. Also, besides that, one of the most important tasks is to reduce the cost of transporting payloads from low orbits to higher orbits. A reusable orbital transfer vehicle with electrical rocket propulsion system can be an effective solution for achieving both of these objectives. The reusable orbital transfer vehicle structure is a multi-section large truss. Such structures have several variable parameters such as: diameter of the rods, rod wall thickness, number of sections, the radius of the base of the structure. When designing large space frame structures, it is necessary to determine the design with the maximum dynamic properties and the minimal mass. This work uses optimization methods to solve the problem of finding the design of the frame structure that is optimal from the standpoint of mass minimization while meeting the requirement to minimize the first natural frequency. It also solves the problem of transient dynamic loads on the structure of the electrical thruster mount during thruster firing. The time dependence of the maximum equivalent stresses is determined.