MODEL DISCLOSURES OF A FOUR-LINK ROD STRUCTURE WITH A MOVING REFERENCE POINT

Abstract

A method for constructing a geometric model of the process of disclosing a rod structure under zero gravity is given. A feature of research is that the structure is not fastened with its “initial” point to a massive object in space. An analogue of the attachment point in our case is the reference point (the term of the authors), which moves in space. The initiation of the movement of the rod structure provides for the following. In the initial position, the four-link (as an example) rod structure is located on the surface of the spacecraft, so that its links form a straight line. The rod structure is set in motion due to the simultaneous operation of the squibs located in the nodes of the structure [1,2]. As a result, the rod structure should be separated from the surface of the spacecraft and, rotating, should move in space within a conventional plane. The task is how to calculate the magnitude of the charges of the squibs, as well as how to determine the direction of action of these squibs so that the core structure acquires eventual (possible under certain conditions) configurations. The logical question “how to catch” the retractable bar structure can be solved by carrying out similar measures by sending the second bar structure “towards” the first structure. A variant of such a scheme is considered in this paper.

The results obtained allow us to simulate the motion paths of each node of the bar structure. The studies are based on the main provisions of Lagrangian mechanics, with the help of which it was possible to describe a geometric model of the process of opening a four-link structure taking into account its main parameters, as well as the conditions of non-attachment to the spacecraft.

The reliability of geometric modeling of the disclosure process can be seen by viewing computer animations on the site [3].

Key words: four-link bar structure, Lagrangian mechanics, generalized coordinates, trajectories of movement of nodal points.