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Information × Registration Number 0206U005398, 0101U001599 , R & D reports Title Investigation of free and controlled operation modes of space-based and ground-based transformable spatial-developed mechanical systems under wide spectrum influences. popup.stage_title Head Alpatov Anatoliy Petrovich, Доктор технічних наук Registration Date 22-05-2006 Organization Institute of Technical Mechanics of NASU and NSAU popup.description2 The research subjects are transformable 3D me-chanical systems. The research goal is to develop methods, mathemati-cal models, algorithms and computer programs for studies in process of operation of advanced space-and ground-based transformable 3D mechanical systems, to made technical recommendations and to propose calcu-lated techniques for designing such systems. The methods used: information and analytical method, mathematical modeling, computer simulation, methods of theoretical mechanics. New design of gravitational stabilization of space-craft is proposed using the tethered system. Methodic problems on selection of parameters for the system with a tethered and a hinged connection are solved. A program package is created to compute the system dynamics. The effects of stabilization system parameters on the spacecraft dynamics are analyzed. A general mathematical model of the dynamics of the space tethered system stabilized by rotation as a system of clastically connected solids is built. The frequency analysis of oscillation of the space tethered system stabilized by rotation is made, as well as analytical estimation of frequencies is presented a program package for computing the system dynamics is developed. Ways of airborne deploying are analyzed for the class of systems under consideration, and the most rational ways are chosen. The effects of structural parameters and initial motion data on processes of stabilization are considered. Based on the similarity theory for mechanical systems, requirements for ground-based experimental studies are established and mock-ups of dampers are presented. Test benches are developed and manufactured. A mathematical model of the dynamics of the experimental tethered system is built, and tech-niques for grand-based experimental studies of the dynamics of the rotatable tethered system with a damper are proposed. Processes in shaping large space transformable stayed reflectors are studied. Investigations are aimed at finding the required shape of the reflecting surface in circumstances where perturbances occur primarily temperature ones. The basic design of the reflector is the shaping element a plane meridia chain. Mathematical models for shaping of the meridianal chain are built and methods for compensating temperature distortions of its shape are proposed. With allowance made for a possibility of engineering realization of compensative methods algorithms of control of the reflecting surface shape are proposed and evaluations of their efficiency are performed. A model of the dynamics of the shaping element of the reflector is built and an algorithms and a computer program to solve the motion equations are developed. The dynamic models allows to establish requirements for operating conditions of the reflector as a 3D peripheral element of spacecraft from the view-point of the required shape of the reflecting surface. A new approach to solution of the problem in determination of acceptability of the operating characteristics of orientation control and stabilization ofspacecraft in different possible situations is proposed. Practical techniques for computer building mathematical models and visualization the results of simulation of transformable mechanical systems are examined and developed. Applications: studies in the dynamics and optimization of processed of a stabilized motion of complicated mechanical systems, the development of principal designs and selection of design parameters of transformable 3D mechanical structures. The research methods proposed and calculated techniques are of critical importance for developing advanced projects of Ukraine's space industry. The predicted proposals related to the development of the research subject: the development of efficient designs of dampers for mounting and bodies and a tether, the development of a new design of gravitational stabilization of spacecraft, based on the tethered system by introducting active controlling moments, further development of methods of dynamic simulation of transformable reflectors, mastering newtypes of its designs, studies in processes of shaping and the development of new ways and algorithms for shape controlling. Product Description popup.authors popup.nrat_date 2020-04-02 Close