Development of Models of Opening of Rod Structures for Emergency Rescue Work in Weightlessness

Abstract

To perform rescue operations in weightlessness, a method is proposed for shaping bar structures, the elements of which are connected like a four-link pendulum. The movement of the links of the structure occurs due to the action of the impulses of the pyrotechnic engines on the end points of the links. The description of the movement of the resulting inertial opening of the rod structure is made using the Lagrange equation of the second kind and, taking into account the conditions of weightlessness, constructed using only the kinetic energy of the system.
 The relevance of the topic is determined by the need to improve and study new technological schemes for opening the frameworks of space infrastructures. Among them are frames of structures of mechanical grippers (such as "robot arms") located outside the spacecraft.
 On the basis of the inertial opening of four-link rod structures, schemes of manipulator action for capturing cylindrical bodies, the axes of which are parallel or perpendicular to the surface of the spacecraft, have been developed. The parameters and initial conditions for starting the movement of a four-link rod structure are determined in order to obtain the necessary arrangement of the links. It is shown that for the implementation of variants of inertial opening it is necessary to apply a set of unified pyrotechnic devices, the impulse values of which are determined by the coordinates of the vector U1={0.1, 1.9, 1.3, 2.5} conventional units. Graphs of the change in time of the functions of the values of the angles as generalized coordinates are constructed.
 The results are intended for geometric modeling of options for opening four-link bar structures under weightless conditions. For example, frames for orbital infrastructures, as well as mechanical manipulators for capturing space objects